Out of curiosity, to those of you with emissions delete tuners, what kind of mileage gains are you seeing, and what tune seems to net the best increase?

No one??:confused:

18mpg city. 22mpg highway. hot tune.

18 city? How do you drive? I can't get 15 no matter what I do, highway or city.

18mpg city. 22mpg highway. hot tune.

Impressive, What was it before though? What did you gain??

Thanks

Bump anybody else?

Wild tune, 20mpg(imperial) hwy.

18 city 20 hwy on hot tune

18 city is awesome. I average 13-14 in the city stock.

That's what I averaged before the tune even with no power selected and the dpf removed I get 16 to 17 city. Got a 600 mile trip this weekend and am going to leave the truck on no power and see what kind of mileage I get

I see 16 in the city and 20-22 on the freeway with my stock system! Im stooked!

^^^^X2 Same as above...stock.

I sure wish I was that lucky... 14 city 16 Hwy with 3,000 Miles.

right at 10,000. Im running a fuel additive/Cetane booster which has cut my regens by 30 percent, that alone has skyrocketed my MPG.

Here's an honest answer. I get about 17 on the interstate, if I drive below 70. Average 14 in town with a few highway miles in between there. I do have a bigger tire. But guys getting 22mpg? Come on!! I got 19 coming back from PA to Texas with the stock tires. That was all interstate highway miles with the cruise set at 72mph. And it's downhill all the way.

Lmmowner. What additive are u using?

Mileage is pathetic on these trucs
I am making 17.5L/100 which is around 15 MPG overall average with intake turbo back exhaust and H&S tuner

I dont understand why they wont make mileage........

Mileage is pathetic on these trucs
I am making 17.5L/100 which is around 15 MPG overall average with intake turbo back exhaust and H&S tuner

I dont understand why they wont make mileage........


Power=fuel used. Can't make 400/800 and get great mileage due to our great EPA. I need to move to the cities with no stop lights or signs and get 18mpg!:rolleyes: I would like to know what they consider "city". No way an 8000lb plus truck gets 18mpg in a city, stop/go situation. :bsmeter:
That's better than gasser city rating in a half ton truck. Just doesn't happen. Maybe if you have a 25mile trip and get stopped by 4 stop lights with in the first mile and then drive 24 miles at 55-65mph, yeah, it could get up to 18, but to me, that isn't city. City is stoplight to stoplight, stop sign to stop sign, traffic all around you, speed up, slow down, etc. Just won't get 18mpg in that type of CITY driving. Chris

Power=fuel used. Can't make 400/800 and get great mileage due to our great EPA. I need to move to the cities with no stop lights or signs and get 18mpg!:rolleyes: I would like to know what they consider "city". No way an 8000lb plus truck gets 18mpg in a city, stop/go situation. :bsmeter:
That's better than gasser city rating in a half ton truck. Just doesn't happen. Maybe if you have a 25mile trip and get stopped by 4 stop lights with in the first mile and then drive 24 miles at 55-65mph, yeah, it could get up to 18, but to me, that isn't city. City is stoplight to stoplight, stop sign to stop sign, traffic all around you, speed up, slow down, etc. Just won't get 18mpg in that type of CITY driving. Chris

Actually epa + poor tuning = poor mileage
A Diesel engine is like a big pump. The more effecient the better the HP. The more the HP the better the mileage. My truck has no emmsions left on it and I am lucky to get 15MPG

Power=fuel used. Can't make 400/800 and get great mileage due to our great EPA. I need to move to the cities with no stop lights or signs and get 18mpg!:rolleyes: I would like to know what they consider "city". No way an 8000lb plus truck gets 18mpg in a city, stop/go situation. :bsmeter:
That's better than gasser city rating in a half ton truck. Just doesn't happen. Maybe if you have a 25mile trip and get stopped by 4 stop lights with in the first mile and then drive 24 miles at 55-65mph, yeah, it could get up to 18, but to me, that isn't city. City is stoplight to stoplight, stop sign to stop sign, traffic all around you, speed up, slow down, etc. Just won't get 18mpg in that type of CITY driving. Chris

My 7200 pound burb has gotten right at 20 in pure city driving, but that's an LB7 with 3.42 gears and 245/75/16 tires.

Mileage is pathetic on these trucs
I am making 17.5L/100 which is around 15 MPG overall average with intake turbo back exhaust and H&S tuner

I dont understand why they wont make mileage........

That's 13.4 US MPG, actually. Terrible. Something is wrong with your truck, or your driving style. I get about 14.0l/100k with my old 6.5 with mixed city and highway. That's 16.8 mpg.

That's 13.4 US MPG, actually. Terrible. Something is wrong with your truck, or your driving style. I get about 14.0l/100k with my old 6.5 with mixed city and highway. That's 16.8 mpg.

Bone stock, 15.3 towing 6k. Empty at 63 on the freeway I see anywhere from 19-21 depending on the terrain.

Has anyone with a HS tune and Turbo back exhaust tried running in stock mode to check for mileage gains?
I know its not the most appealing thing to want to do however, I would like to believe that if the LML was stock with out the emissions junk we could see a slight improvement???
Or I could be wishfully thinking again....

I think it would....... I hope we hear some good responses....

Im still waiting on my MBRP exhaust to arrive or I would try it. In theory, I would think it would help....?

The Very Very Very best I have ever seen at 70-72mph all interstate is about 18mpg thats with very little wind. I usually see 14-17 city/hwy mix average I not dissapointed yet cause I dont have 5k on the truck yet but towing my 17.5ft fishing boat Im lucky to see 15 that boat prolly doesnt weigh 3000lbs maybe 2500lbs Im not too impressed with that.

right at 10,000. Im running a fuel additive/Cetane booster which has cut my regens by 30 percent, that alone has skyrocketed my MPG.

Mine saw significant mileage improvement when it reached 10 -11,000miles. Maybe it's the mileage on the truck and not the fuel additive.

Have you tried stopping the additive to see if it goes back down?

Bump!

Bump bump

I'll share my limited experience so far with a full delete (AFE downpipe and 5" exhaust w/ muffler), Banks CAI, and H&S Black Maxx set at "Wild".

From picking the truck up to my office, which was about 80% freeway with a section of a few miles of slow (25 MPH) stop and go street light traffic I saw just under 19 MPG... and I did hammer it a few times!

I took a few coworkers for short joy rides and dropped it into the high 17s, but that was all stop light to stop light WOT smashing.

Then I went and grabbed my trailer (28' AL enclosed car hauler, haven't weighed it yet) and got ~12.5 MPG going to pick up my sand car. Again, probably 80% freeway but some heavy rush hour traffic (all the way down to stop and go at some points). After picking up the car there was very little traffic getting home, but I stopped off for some dinner which added some more city driving. By the time I parked I was at about 13 MPG.

For reference the best I ever saw before unloaded was 18 MPG pure freeway under perfect conditions. The best I ever did towing was about 11 MPG, again pure freeway and great conditions.

I'd say I'm seeing something like a 2 MPG gain, before you factor in regen losses. But that's based off of less than a tank so far.

-TJ

I'll share my limited experience so far with a full delete (AFE downpipe and 5" exhaust w/ muffler), Banks CAI, and H&S Black Maxx set at "Wild".

From picking the truck up to my office, which was about 80% freeway with a section of a few miles of slow (25 MPH) stop and go street light traffic I saw just under 19 MPG... and I did hammer it a few times!

I took a few coworkers for short joy rides and dropped it into the high 17s, but that was all stop light to stop light WOT smashing.

Then I went and grabbed my trailer (28' AL enclosed car hauler, haven't weighed it yet) and got ~12.5 MPG going to pick up my sand car. Again, probably 80% freeway but some heavy rush hour traffic (all the way down to stop and go at some points). After picking up the car there was very little traffic getting home, but I stopped off for some dinner which added some more city driving. By the time I parked I was at about 13 MPG.

For reference the best I ever saw before unloaded was 18 MPG pure freeway under perfect conditions. The best I ever did towing was about 11 MPG, again pure freeway and great conditions.

I'd say I'm seeing something like a 2 MPG gain, before you factor in regen losses. But that's based off of less than a tank so far.

-TJ


Thanks for the feedback

How were EGTs on wild setting while towing your trailer?

I am really appreciating all the feed back...

If we are not seeing huge improvements... it is really worth deleting and losing your warranty?

If GM gets the DEF/frequent regen issue figured out, I may leave me diesel clean...

Thanks for the feedback

How were EGTs on wild setting while towing your trailer?

Not bad, highest I got to was just under 1250 on a short grade (too short for it to knock down a gear). When I went up Cuesta Grade (long and steep) at 55 I just knocked it down to 4th and it held right around 1000 on the EGTs.

FWIW I got weighed on the way back, pretty light load for a D'max.

Gross 16560lbs
Drive 9320lbs
Tandem (trailer) 7240lbs


I saw about 11 MPG total towing for the trip excluding the time in the sand. That's actually only about 1 MPG more than I used to see, though I might have been going a bit faster to catch some friends that were a few miles ahead of me.

I am really appreciating all the feed back...

If we are not seeing huge improvements... it is really worth deleting and losing your warranty?

If GM gets the DEF/frequent regen issue figured out, I may leave me diesel clean...

Unless you drive a LOT of miles you'll never even recover the cost of the exhaust and tuner on the MPG increases. However, it's like a whole other truck with the tune (and I'm not even on HOT yet). Throttle response is way better, it builds boost much quicker, the low end torque gains are even more impressive than the big HP gains. No more annoying regen which seems to kick on EVERY time I am about to get to my office then I end up driving around for a half hour for no reason. All of that makes it worth it to me.

-TJ

TJ,

I agree with you those are some valid points you make.

What has your dealer said?

My other question is:

What if there is a failure in the tuner? Is the truck dead on the side of the road or do you get a bunch of codes??

I am just curious. Do we rely on the GM junk emissions system or an aftermarket electronic piece of equipment to keep the truck running? I am not being critical AT ALL. I am just playing devils advocate that's all.

I just want to know what happens if per say my tuner would take a dump.

Believe me, I am considering the delete. I just don't know if I want to part with most of the warranty on my 64K truck.

My truck went from 13.3 in the city to 16.4 after the delete, about 750 miles. My mini max is always set to hot. I am not sure if the mileage increase can all be attributed to the delete because the truck only has 4000 miles on the clock. I would assume it will continue to get slightly better until 10k or so.

I went from 13.8-15.4 with city driving. So far I have put about 3k on since the chip and full exhaust. I currently have 6K on the truck now.

TJ,

I agree with you those are some valid points you make.

What has your dealer said?

My other question is:

What if there is a failure in the tuner? Is the truck dead on the side of the road or do you get a bunch of codes??

I am just curious. Do we rely on the GM junk emissions system or an aftermarket electronic piece of equipment to keep the truck running? I am not being critical AT ALL. I am just playing devils advocate that's all.

I just want to know what happens if per say my tuner would take a dump.

Believe me, I am considering the delete. I just don't know if I want to part with most of the warranty on my 64K truck.

My dealer hasn't said anything yet... though I'll just say they are "friendly" and leave it at that. If you don't have a close relationship with your dealer expect your powertrain warranty to be voided instantly. Even if you do have a close relationship if you blow a trans (or maybe motor) and GM gets involved your claim will be denied as well (nothing your dealer can do about it).

H&S would probably be better suited to answer your question about the tuner failure. However, the way I understand it is that once the tune is loaded in the truck the tuner is just providing gauges at that point. If the tuner itself died your truck would still run, you just wouldn't have the gauges. However, I am not certain.

I certainly hear you on the warranty issue, it really does hurt to throw out the warranty on a trans that is at least $5k to rebuild and motor that is probably $10k to build. The truck does drive so much better though I'm glad I did it... but it's certainly not for everybody.

I'd suggest trying to find a local LML with the deletes and tuner and take a ride in it (or if the owner is kind enough drive it) and see if the gains are worth it to you. I totally understand where you're coming from, and happy to help.

-TJ

I bought an LML about a week and a half ago and I have been contemplating whether or not to get the H&S tuner and delete the DPF system as well. I had an LBZ with John Kennedy's tow/performance tune, blocked egr, and 4" downpipe-back exhaust. I drove teh truck 206k miles and there is no way I recovered my expense in fuel savings. (I did the math). Having said that, there was a noiticeable difference in performance. I have only burned about 2 1/2 tanks of fuel and I am already getting better (hand calculated) mileage that I got from my tuned LBZ. Unless there is CONSIDERABLE mpg gains by deleteing the dpf and/or I start having problems from the system, I just can't justify the expense of deleting it all. IIRC, I had to have a MINIMUM of a 2 mpg gain in fuel economy over 125-150k miles to pay for all the mods I did to the LBZ. At the very best, I gained 1.5 mpg. It just didn't add up for me.

I am thinking along your lines...

I may not screw with it unless I have problems....

At least I know I have an out if the issues start....

I can deal with the frequent regens until they find a ECM fix...

first time that DEF tank leaves me stranded....BYE BYE

I think will just keep up on the deletes and follow everyones reports and experiences...this way if I NEED to take plunge, I will.

Money is not the issue for me. I never look at the improvements to the truck from a "Will I gain my money back" standpoint. I have always been a gear head and cant leave things alone! How ever I know some do look at the "bang for buck" equation.

Not being critical at all. Its more of a hobby for me to make it better. If better fuel economy comes my way then great. I would strictly do to improve RELIABILITY. '

[QUOTE=tjZ06;4356114]Not bad, highest I got to was just under 1250 on a short grade (too short for it to knock down a gear). When I went up Cuesta Grade (long and steep) at 55 I just knocked it down to 4th and it held right around 1000 on the EGTs.


FWIW I got weighed on the way back, pretty light load for a D'max.

Gross 16560lbs
Drive 9320lbs
Tandem (trailer) 7240lbs

That is really amazing if your sensor is in the manifold. My LML will hit 1200 unloaded with only moderate acceleration 100% stock. Pulling our 5th wheel 1500 degrees is a regular occcurance, but since I am not running a tune I am trusting that GM must consider this to be an acceptable temp. I was always in a butt pucker when the old LBZ got close to 1500, which took some really hard pulls, but now with what I am seeing with the stock LML I assume that my former concerns were unwarrented, I hope. In any case, if it burns down now they have to replace the melted remains, though I'm still out the extreme inconvienance of being on the road broken down with a 15k sail attached to the truck. Actually don't think that's going to happen, I trust GM more than that. ECT are also higher on the LML=much more fan clutch engage. Still like the truck; what if I had to tow with a Fart or Dodger :(, no way.

[QUOTE=tjZ06;4356114]Not bad, highest I got to was just under 1250 on a short grade (too short for it to knock down a gear). When I went up Cuesta Grade (long and steep) at 55 I just knocked it down to 4th and it held right around 1000 on the EGTs.



FWIW I got weighed on the way back, pretty light load for a D'max.

Gross 16560lbs
Drive 9320lbs
Tandem (trailer) 7240lbs
That is really amazing if your sensor is in the manifold. My LML will hit 1200 unloaded with only moderate acceleration 100% stock. Pulling our 5th wheel 1500 degrees is a regular occcurance, but since I am not running a tune I am trusting that GM must consider this to be an acceptable temp. I was always in a butt pucker when the old LBZ got close to 1500, which took some really hard pulls, but now with what I am seeing with the stock LML I assume that my former concerns were unwarrented, I hope. In any case, if it burns down now they have to replace the melted remains, though I'm still out the extreme inconvienance of being on the road broken down with a 15k sail attached to the truck. Actually don't think that's going to happen, I trust GM more than that. ECT are also higher on the LML=much more fan clutch engage. Still like the truck; what if I had to tow with a Fart or Dodger :(, no way.

What are you using watch your EGT's? Do you have a probe in the manifold?

[quote=moss6;4361090]

What are you using watch your EGT's? Do you have a probe in the manifold?

I'm watching using the H&S Black Maxx, and yes I added a probe in the manifold as opposed to using one of the factory pyros that are too far downstream. This is all on the "Wild" tune with the H&S and a full delete exhaust (AFE downpipe and 5" dp-back w/ muffler). I'm sure all the delete stuff and the giant piping help keep the EGTs down despite the increased power production. What are you towing? I just posted in another thread about how low my ECT and Trans temps have been. I hardly ever hear my engine fan kick in.

From the other thread:
WOW! LMLs run nowhere near that hot. Like I said, big grade, 16560 gross weight, 55mph (where all my buddies have to do 45 or less) I saw a true 210-215 coolant temp (on the H&S, not on the dash which always just sits on 210, even when the truck is as cool as 185). Trans didn't even make it to 200, I think it was around 170 (which is the hottest I've ever seen it). It was only about 80-85 out though. Cruising around with no load the trans stays about 130 on the freeway, engine 185. Around town with lots of stop and go (and therefore shifting) trans will run about 150. My oil pressure seems a lot higher as well.

I seriously don't think I've ever even heard my fan in my truck other than sometimes at startup (I'm told the computer engages it to add extra load to the motor for warmup since the tstat is closed and water is not circulating through the radiator anyway it doesn't provide cooling).


-TJ

[quote=Iceman56;4361122]

I'm watching using the H&S Black Maxx, and yes I added a probe in the manifold as opposed to using one of the factory pyros that are too far downstream. This is all on the "Wild" tune with the H&S and a full delete exhaust (AFE downpipe and 5" dp-back w/ muffler). I'm sure all the delete stuff and the giant piping help keep the EGTs down despite the increased power production. What are you towing? I just posted in another thread about how low my ECT and Trans temps have been. I hardly ever hear my engine fan kick in.

From the other thread:


-TJ

My sensor is in the manifold, exact same place (and the same sensor and guage) as was on the LBZ; that is why it is easy to make the comparison and state that the LML's exhaust temps are much higher than my old LBZ pulling the same load over the same roads in the same weather conditions. Same goes for the water temps, although the LBZ was cheating a good bit with all the extra cooling capacity that I added. To put a guesstimate on it I'd say the fan LML clutch engages 85% more often than the LBZ. As for the transmission temp's, the LML is far far superior; it is near impossible to get it hot enough to even get a hot fluid level reading on it even when towing. Not towing it can't be done, can't believe there is that much difference, cooler even with the Mike L cooler on the LBZ.

[quote=tjZ06;4361845]

My sensor is in the manifold, exact same place (and the same sensor and guage) as was on the LBZ; that is why it is easy to make the comparison and state that the LML's exhaust temps are much higher than my old LBZ pulling the same load over the same roads in the same weather conditions. Same goes for the water temps, although the LBZ was cheating a good bit with all the extra cooling capacity that I added. To put a guesstimate on it I'd say the fan LML clutch engages 85% more often than the LBZ. As for the transmission temp's, the LML is far far superior; it is near impossible to get it hot enough to even get a hot fluid level reading on it even when towing. Not towing it can't be done, can't believe there is that much difference, cooler even with the Mike L cooler on the LBZ.


Yeah my fan seems to run all the time as well. I was very curious to know what the EGT's were on a stock LML since it's basically a LMM with a good sized tow tune and still has all the restriction in the exhaust.

Has anyone with a HS tune and Turbo back exhaust tried running in stock mode to check for mileage gains?
I know its not the most appealing thing to want to do however, I would like to believe that if the LML was stock with out the emissions junk we could see a slight improvement???
Or I could be wishfully thinking again....

This is what I would likme to know, surely someonr has tried it!

This is what I would likme to know, surely someonr has tried it!

X2. Wanting to know the same thing

My last tank of fuel was on the hot setting. This tank is on the Wild setting. I'll go back to stock next tank and let you know the end of next week if its improving. I put an app on my iphone and I have tracked every drop of diesel so far. So I will be able to tell you how many miles to gallon better it will do. Everyones situation is different on how they drive so I will tell you how much my truck improved now vs before.

Good deal thanks. Including driving conditions too
Was there any diff between wild and hot?

My last tank of fuel was on the hot setting. This tank is on the Wild setting. I'll go back to stock next tank and let you know the end of next week if its improving. I put an app on my iphone and I have tracked every drop of diesel so far. So I will be able to tell you how many miles to gallon better it will do. Everyones situation is different on how they drive so I will tell you how much my truck improved now vs before.

What App are you you using? is it any good?

I have been running mine on the stock setting for around 2 weeks now, after 250 miles, I still have just over half tank left, and dic is an overall average of 17.8. I am regularly seeing over 20mpg on highway unloaded at 70. I was never seeing over 18 stock, and my overall average for the first 10000 miles was 13.58. It is a VAST improvement even on the stock setting! It still makes me smile ear to ear simply from the sound difference!

I am using an app called Pocket Garage. It lets you put in fill up's and service records and such. Its nothing fancy but its a good way to track.
As far as driving conditions I rarely drive a full tank down the free way. If we are going somewhere far we usally take our suv. Here is what my truck sees. I live on on of our cattle farms. I start my morning there then drive 38 miles to another one of our cattle farms everyday. I hit 8 stop signs in rural Idaho each way. So I am accelerating 0-60 at least 16 times a day. Before the chip and pipe I was averaging 14.5-15.5 miles per gallon. I did take it on 1 trip to utah that I averaged a true 16 down and back(i was at 17 till i hit a reburn). Since the chip I am 16.5-17. My last tank was 17.08 on the wild setting. I will have an update on stock form by the end of the week.

I bought an LML about a week and a half ago and I have been contemplating whether or not to get the H&S tuner and delete the DPF system as well. I had an LBZ with John Kennedy's tow/performance tune, blocked egr, and 4" downpipe-back exhaust. I drove teh truck 206k miles and there is no way I recovered my expense in fuel savings. (I did the math). Having said that, there was a noiticeable difference in performance. I have only burned about 2 1/2 tanks of fuel and I am already getting better (hand calculated) mileage that I got from my tuned LBZ. Unless there is CONSIDERABLE mpg gains by deleteing the dpf and/or I start having problems from the system, I just can't justify the expense of deleting it all. IIRC, I had to have a MINIMUM of a 2 mpg gain in fuel economy over 125-150k miles to pay for all the mods I did to the LBZ. At the very best, I gained 1.5 mpg. It just didn't add up for me.

Well, I did the math and came up with the following numbers:
When I added up the cost of DEF @ $5.20/gal, 1000 miles/gal DEF + the cost/mile of fuel I figured that if I gain 1 mpg the delete package will pay for itself in ~81k, if I gain 1.5 mpg it wil pay off in 62k, and if I gain 2 mpg, it will pay off in 51k. I will keep the truck for at least 200k, so I should come out ahead.

So the best gains you guys are seeing are 4-5mpg empty? Does that require the deletes and exhaust or just with the H&S? My gf just bought an '11 LML and we wanted to tune it in hopes of getting her better milege since she drives 60mi a day for work on interstate. She doesn't like spending $850+ for a H&S but also doesn't want to get 15mpg empty either 20mpg would make the H&S look way better.

Wish my GF drove a diesel...:) I think in the future, with HS "improvements", the MPG will get better... But that's just a guess. I really don't think you would lose any MPG. IMO, it was worth it for me just in the responsiveness of of the truck. I'm not sure that this helps at all, but it might be food for thought.

I'm just trying to justify the cost for her. This is her 3rd diesel and the last was an 06 LBZ with a Superchip set on 120, straitpiped and leveled on 285"s and it ran good. Still hard to beat my 600hp LB7 that will get 20pg though :D

Wish my GF drove a diesel...:) I think in the future, with HS "improvements", the MPG will get better... But that's just a guess. I really don't think you would lose any MPG. IMO, it was worth it for me just in the responsiveness of of the truck. I'm not sure that this helps at all, but it might be food for thought.

I have a 2500 Denali and now have 25000 miles on it with no mods of any kind. I get 16 driving to work which is mixed freeway and morning stop and go traffic. If i run it on the interstate at 85 & 90 it will get 18.5 to 18.8. I love my truck except my brakes squeal when stopping and have been for 15000 miles

I have a 2500 Denali and now have 25000 miles on it with no mods of any kind. I get 16 driving to work which is mixed freeway and morning stop and go traffic. If i run it on the interstate at 85 & 90 it will get 18.5 to 18.8. I love my truck except my brakes squeal when stopping and have been for 15000 miles

yeah ok, I can't get that mileage at that speed in my wifes subaru:rolleyes:

I think for those showing 18 city/20 highway, your city rating is really close to your highway rating. So, I'd check your definition of city driving. ;)

My 2500 LML would average 13.8-14.2 with my mostly city driving and a few short stretches of highway. I just refilled my dually, and it got 14.2 this last tank. On the highway with no wind, both trucks would get right at 18 MPG. This is the typical average. I've seen better and worse, but the wind is usually helping/hurting. Both trucks are in bone-stock trim. I've contemplated a DPF delete on the dually, but I'm concerned with getting checked when crossing various state lines pulling the 48' trailer.

Just brought home a '11 2500HD LML. I don't like the "cat pee" tank under the passenger, door, and a friend who did a DPF delete on his Dodge is encouraging me to do the same. We don't live in an emissions-inspection area, and I've told him that the first time the cat pee injection system gives me trouble it's getting yanked. Or once it's out of warranty and stuff starts to break. I'd be doing a stock tune (I'm paranoid about protecting the transmission), so the only things I'm aiming for are an increase in mileage and an increase in reliability. After the first 230 miles, the DIC is saying 16.8 mpg (I don't think it's been reset since the truck was built). Not too bad considering it read 13 when I left the dealership and I'm doing a lot of throttle/speed changes (for break-in purposes).

So, what is the minimum set of stuff to buy and how much $$$ are we talking about to get rid of the emissions hardware and take care of the computer side of things?

$1200-1500 to get rid of the emmisions crap. I am seeing about 1-1.5 mpg increase. Not as much as I had hoped for, but better than nothing.

Okay, that's in-line with what I'm finding. I found one example of a complete kit for $1375. If my mileage goes from 16 to 17 mpg, it'll take 90k miles to recoup the cost with diesel here running $4.159/gallon. If I can get 1.5 mpg gain, it would pay for itself in 62k miles.

The things that are hard to put a dollar figure on are the simplicity, improvement in reliability, and reduced fire hazard (this is a farm/ranch truck). Wildfire is a big issue out here, and the cheatgrass likes to grow tall. The Forest Service wasn't happy when DPFs became mandated... some of their wildland firefighting trucks have gone back to gas because of the fire risk created by the new emissions systems. Here's their study:
http://www.fs.fed.us/eng/pubs/pdf/08511816.pdf

My report of some of their trucks going back to gas is based on looking at the parking lot outside of my workplace (we share a building with the USFS office for this region).

Okay, that's in-line with what I'm finding. I found one example of a complete kit for $1375. If my mileage goes from 16 to 17 mpg, it'll take 90k miles to recoup the cost with diesel here running $4.159/gallon. If I can get 1.5 mpg gain, it would pay for itself in 62k miles.



Your math is very similar to mine. I have it figured at an 81k mile payback for a 1 mpg increase and a 62k mile payback for a 1.5 mpg increase. I put close to 50k a year on my truck so either way it will pay back before I have to trade the truck.

When you guys are doing your mileage, are you driving around with a/c on or with windows down? I ask because my Tahoe can get 18-19 with windows down and a/c off on the highway. But if the a/c is on it gets 13.5 on highway no matter how I try. It's been this way since I bought it.

I'm asking because I am really thinking about getting a new 2500 crew cab dmax. But I want to know what kind of mileage I'll be looking at.

FYI: http://special-reports.pickuptrucks.com/2010/08/2010-hd-fuel-economy-test.html

2500HD 6.0L LY6 gas: 14.10mpg empty / 10.16mpg towing 10,000lb trailer
2500HD 6.6L LML diesel: 19.66mpg empty (+39.4%) / 13.28mpg towing 10,000lb trailer (+30.7%; no regens during test)

I find it odd that, compared to the gas engine pickup, the LML pickup had a larger advantage when empty than when towing a 10k trailer.
Unless their test is flawed, this turns the normal assumption (that diesels have an even bigger fuel economy advantage when towing) on its head.
And this comes on top of them making the test less like the real-world situation by forcing a regen before the test began.

I'd love to know how they got 19.7 mpg empty... I was getting 16.5mpg empty, but current tank has dropped to an indicated 14.2 due to an extra regen mid-tank.

I know, I know... it isn't a Prius. I don't use mine like one, my wife and I have daily-driver cars for that. Even so, that 5 mpg is nothing to sneeze at. We're talking about a 25-30% difference in fuel costs.

Do I just need to ignore fuel economy until my truck has 10k miles on it and has been thoroughly run in?

I am not sure how they got that 19.7 mpg either. I highly doubt it is a true average, they probably reset the DIC and recorded a straight highway mileage with no stops. My best mileage was in OCT 2010 when I first purchased the truck and I was getting 15-16 average until one of the reflashes that was done on my truck. Since I have been complaing to the dealer about a drop I begin recording every tank at the pump and putting it in a log book I keep in the truck. My worst tank empty has been 11.8mpg average and my best has been 14.03mpg. These are all empty averages with a city/highway/backroads mix. I do have to drive my truck in town frequently but it was the same driving I did when I bought the truck back in OCT 2010 so the mileage should be the same or better now that I have more miles on the truck. I will be taking it back to the dealer tomorrow for them to keep a few days to do some real world testing on the truck. I would be happy to at least get it back to what I was averaging when I first got the truck 15-16 but I think the 19.7 and some of those numbers are a little far fetched for a stock truck unless it is continuous driving down a highway.

http://www.fuelly.com/driver/cowdoc/silverado-2500-hd?fu=1884835

Here are the fuel mileage records since I bought my truck (used) at the end of September. I installed the H&S tuner with deletes after the 6th tank of fuel. As you can see, my overall average is 19 mpg including about 6% towing my horse trailer. Not much way you can falsify these numbers. Having said that, my mpg's only improved 1-1.5 mpg after the delete. Most oif my driving is interstate and rural roads. Very little city driving.

I'd love to know how they got 19.7 mpg empty... I was getting 16.5mpg empty, but current tank has dropped to an indicated 14.2 due to an extra regen mid-tank.

I am not sure how they got that 19.7 mpg either. I highly doubt it is a true average, they probably reset the DIC and recorded a straight highway mileage with no stops.

Check these factors: Tire pressure, type of tire, front end alignment, driving conditions. Wet roads (more common in winter) create a lot more drag.

The article here: http://special-reports.pickuptrucks.com/2010/08/2010-hd-fuel-economy-test.html
explains how they tested for fuel economy. They carefully measured the fuel used for the ~159 mile distance they drove.
A DIC reset while crusing on the highway should result in higher fuel economy than 19.7, at least it does on my van.
But they rigged the test somewhat in favor of the diesels by doing a regen before the test, so their 159 mile test does not include any fuel wasted during regen., unlike normal driving. I also wonder if the outside temperature was the same both times they filled the tanks. Gas (and diesel) pumps do not adjust for temperature. They are calibrated for a "normal" temperature. Presumably the temperature of the fuel in the ground didn't change much if any between the two fill ups. They did use the same pump. Not all pumps are accurate though. Either that or my 31-gallon fuel tank is big enough that I drive up to a fuel pump, and put more than 32 gallons in it.

This should make it easier than the link.

The only rivalry in Michigan as intense as the one between the HD manufacturers is the spirited competition between the University of Michigan in Ann Arbor and Michigan State University in East Lansing. That’s why it made sense to drive the trucks between the two cities for our fuel economy challenge.

The trucks ran the approximately 150-mile circuit twice, for a total of around 300 miles, once unloaded and once towing a trailer. Tow/haul mode was used when the trucks were towing.

We started our test at the Pilot Truck Stop in Dexter, Mich. The same diesel and gasoline pumps were used for both loop fill-ups, with the same designated “filler” at the diesel and gasoline nozzles, using the same procedures and techniques.

Each truck’s fuel tank was filled to visual sight of liquid at or very near the top of the filler tube. Amounts of fuel were recorded, as well as odometer, tripometer and vehicle mpg computer information. All vehicles were reset at the beginning of the fuel economy test at the pump, and also reset at the end of the first loop at the same pump.

Completed information is presented in two ways below. First, information from each truck is recorded in two charts from both loop 1 and loop 2. Second, vehicles are grouped by class (gas, SRW diesels, DRW diesels) and charted in head-to-head comparison format, both with and without trailers.

How rigorous were we with measuring our diesel fuel economy? We had techs from each of the manufacturers trigger manual service regenerations to clean out the trucks’ diesel particulate filters.

DPFs trap soot, a byproduct of diesel’s lean combustion process because not all of the fuel is burned. After a while, depending on workload and driving distance, the DPF becomes full and needs to be cleaned out, much like a self-cleaning oven. Extra diesel fuel is injected into the exhaust stream to boost temperatures in the DPF to more than 1,000 degrees, incinerating the trapped soot. That process can require up to six-tenths of a gallon of diesel – an amount large enough to impact our fuel economy measurements on a 300-mile drive. That’s why we started each truck with a clean DPF.

We attempted to measure consumption of urea, or diesel exhaust fluid, for the first time. The harder a truck works, the more DEF that is consumed. At the Pilot station, it cost $2.99 a gallon at the pump and $5.99 a gallon by the bottle. Before we started our driving loop, we topped off the Ford and GM trucks – again, the Ram HD trucks are DEF-free – and measured their consumption at the end of both loops. For those interested in calculating their cost per mile, this new fluid addition must be included.

Total DEF measurements were conducted for the test, which included topping off at the beginning of the day, refilling at the end of the day and calculating usage.


Fuel economy and DEF consumption (where applicable) data is displayed below.

http://blogs.cars.com/.a/6a00d83451b3c669e20134864475ce970c-800wi

http://blogs.cars.com/.a/6a00d83451b3c669e20134864480dc970c-800wi

http://blogs.cars.com/.a/6a00d83451b3c669e2013486448150970c-800wi

Yeah, I read the test, so I knew they did a fill-up to fill-up hand calc. Also saw they did the forced regen. Even without a regen, my DIC has never read above 18 (I reset it every time I fill up). Thus far, my DIC has been ~0.5 mpg optimistic, same as every other GM vehicle I've driven with a fuel economy readout (Saturn Sky, GMC Yukon, Chevy Suburban), so it's reasonable to assume my average mileage is not going above what it says.

I think I need to pay less attention to this right now... truck has a whopping 1200 miles on it, still hasn't had the break-in oil change, and it doesn't get driven daily. Bought it to haul heavy stuff, get around on our undeveloped acreage, and carry us safely through nasty weather (snow)... not commute to work while running empty. I'll keep doing my hand calcs. I'm still of a mind to remove the high-temp emissions crap when fire season returns next year, which would have the side benefit of no more fuel-slurping regens. I'd rather my truck not start any grassfires. Not a great way to endear myself to my new neighbors. Screw the EPA... out here in the country we have more immediate concerns, like not burning down each others' homes. Last year a truck with malfunctioning exhaust hardware set fire to roadside grasses about 20 miles from our place. The Monastery Complex Fire, near Goldendale, Washington. Better for everyone's health to use a truck in moderation with fewer emissions controls than use it with all the emissions controls and create a fire hazard.

I'm still of a mind to remove the high-temp emissions crap when fire season returns next year, which would have the side benefit of no more fuel-slurping regens. I'd rather my truck not start any grassfires. Not a great way to endear myself to my new neighbors. Screw the EPA... out here in the country we have more immediate concerns, like not burning down each others' homes. Last year a truck with malfunctioning exhaust hardware set fire to roadside grasses about 20 miles from our place. The Monastery Complex Fire, near Goldendale, Washington. Better for everyone's health to use a truck in moderation with fewer emissions controls than use it with all the emissions controls and create a fire hazard.
I agree, but on the 2011+ it's a lot more difficult. EFILive does not work with the new, securely locked ECM.