Hooked up my travel trailer for the first time this past week. It is a 34' pull behind approx. 8500# loaded and I was carrying 4 plus myself in the cab. The ability to pull was great, no issues on any hill. I especially liked the way it slowed to a stop with the tow/haul mode engaged which allowed me to hardly use the brakes on off ramps. Mileage was not as good as I had hoped. On the 330 mile trip to the beach I was getting around 11 mpg and on the return trip with lots of side/head wind and much colder I got 9 mpg. I started the trip with 4000 on the odometer so I know it is not really broken in yet. Is this type of mileage normal with this weight? After I unhitched and traveled 300 miles with just the 5 of us in the cab and some luggage, I was getting 20+ mpg. Any comments are welcome.
thanks

Empty 20-23 ! loaded = as little as 7.8 (but I do mean loaded )@23000#trailer wt. My truck is stock , the world is flat ! and I love mine ! I hope you enjoy yours as much good luck with it! t

I Haven't towed anything really with mine. just a single jetski traile at the end of the summer. mayber 1300lb at the most. but i have a shell on mine, running a Quadzilla Stealth 2 on Economy mode and Air Raid cold air intake. i average 13.5 - 14 on the highway!!! WHY... i try to drive it like an old man and use the cruise as much as possible around 70 mph. and try to keep it under 2000 RPM.... Whats going on here?????

70 is about 10 over the mpg sweet spot for one thing....

:rolleyes:

07blkLMM, are your mileage numbers from the DIC or hand calculated? They shouldn't be way different from each other, just curious.

I'm a new LMM owner (only 325 on the odo so still doing the initial break in) who bought my LMM just for towing a TT (about 6800 loaded and just me and the wife) so I'm very interested in your numbers. Yeah, your numbers are a bit lower than I would also be hoping for.

zipman brings up a couple of good points. He mentions he has a shell on his truck. I have a shell on my Ford (I'll be installing a P/E Full Metal Jackrabbit (a retractable bed cover) on my LMM). Do you have a shell or some kind of cover over your bed or do you have it open. If open, that might be causing some extra drag and reducing your MPG. As you (and I) know, towing a TT is like pulling an open parachute behind us. I guess reducing any source of drag would help with mileage. How fast were you driving? Faster = lower mileage. Did you use cruise control?

You haven't filled out your sig. Are you driving a single rear wheel or a duallie?

Towing with my Ford gasser, I've gotten used to cruising 60-64 mph and happy to get about 9 mpg but with the LMM and the same speeds, I was hoping for at least 12-14 mpg. I'll be looking forward to hearing updates from you and hoping your numbers go up. When you towing again?

I delivered a tractor in pitts pa the other morn just about 400 miles each way from new york here ! Light load > trailer 1500 . tractor 2200 fold up ramp gate catchin air both ways ! I averaged 15mpg round trip DIC and hand are virtually the same on my truck ! about 12.8 going and about 17.whatever returning empty !
I used the dually

In replying to redmetoc....my mileage was by the DIC but in past hand calculations it has always been within a couple of tenths correct. It do have a hard shell on my bed that weighs 45 pounds I believe, it is lockable also. I have single tires on the back so no dually.
I was following a gasser GMC that was pulling a trailer weighing about 4000# less and he was getting about the same mileage as me. We generally were going 60-65 all the time. The closer we got to our destination the flatter the terrain got and I was really being light on the throttle and in 6th with the torque converter locked or in 5th because of the speed being less.
As I said before, I had no issues with the power because I could move out at will if needed and getting 20+ with no trailer is not bad. That is the best I can do with my Astro van which has a 6 cylinder and I can leave it in the dust. I just was hoping to get 14 or 15 mpg with the trailer in tow.:rolleyes:

I have made a couple of 200 Mile runs towing my 26 ft toy hauler. It tips the scales right at 10K fully loaded with ATV's, full propane bottles and 150 Gal in the fresh water tanks. My first loaded run netted me 8.5 MPG hand calcd. I was worried, that wasn't much better than my '02 6.0L gasser got with the trailer in tow. Next trip, I got 11 MPG with the travel trailer. I think the wind really plays a big part in what mileage I get hauling a 11'6" tall box behind me.

Over the Christmas holidays, I made a tour around Texas visiting family and hauling the camper. It started out getting about 10MPG on a 200 mile trip, but then got 14 MPG on the return leg. I don't know if it is wind or the engine starting to get broken in. I have about 5000 miles on the truck now.

By the way, the first trip when I got 8.5 was with the DPF. THe DPF went away at about 1000 miles, but I haven't missed it.

Cruising unloaded at 65 I can get close to 20 MPG. Running around town I get about 17. These numbers are better than anything I ever got out of my '02 6.0L gasser. The best I could get out of it was 13 cruising downhill with a tailwind.

I'm averaging about 9mpg towing about 8,000lbs. I only have about 6100 miles on the truck though and slightly bigger tires, 285's. I haven't done any performance mods yet.

Hooked up my travel trailer for the first time this past week. It is a 34' pull behind approx. 8500# loaded and I was carrying 4 plus myself in the cab. The ability to pull was great, no issues on any hill. I especially liked the way it slowed to a stop with the tow/haul mode engaged which allowed me to hardly use the brakes on off ramps. Mileage was not as good as I had hoped. On the 330 mile trip to the beach I was getting around 11 mpg and on the return trip with lots of side/head wind and much colder I got 9 mpg. I started the trip with 4000 on the odometer so I know it is not really broken in yet. Is this type of mileage normal with this weight? After I unhitched and traveled 300 miles with just the 5 of us in the cab and some luggage, I was getting 20+ mpg. Any comments are welcome.
thanks

I think you are right in the ballpark of what you will get towing. Maybe alittle better as she breaks in. All depends on your speeds, wind, fuel quality, etc, etc. Excellent mt mileage...

I've only pulled my TT twice, and at the time my truck only had about 2500 miles on it. My trailer weighs around 3500# and I had a truck load of gear. I averaged about 13.5 towing on two lane road and a lot of steep grades. I was averaging about 17.5 empty but I have lost a couple and now I am getting about 15-15.5 empty and I have 5500 on the clock. The loss I experienced is more than likely the winter blend fuel IMO.

Cruising unloaded at 65 I can get close to 20 MPG. Running around town I get about 17. These numbers are better than anything I ever got out of my '02 6.0L gasser. The best I could get out of it was 13 cruising downhill with a tailwind.

X2:exactly:

07blkLMM, well hell, it looks like you were towing "smart" so I'm out of ideas.

DMAX1518 mentions winter fuel blend may be reducing his mileage. Perhaps this is affecting yours too. Not sure if they winter blend in GA.

The main reason I upgraded to a diesel was to tow my RV (not as a daily driver). My Ford gasser handled every towing demand (about 92% of GCWR of 15K) I threw at it and never complained. [Seeing you're from GA, the most impressed I ever was with my Ford towing was when we went north to south on Hwy 19 over the Blue Ridges on our way to Cleveland, GA last spring. Yeah, I was only doing 35 in 3rd on the steepest spots (luckily no one behind us. heh) but lots of reserve power and she was "hummin' ". A very HIGH confidence factor.] With 92K on the Ford odo and about 9K of total towing duties, my (full synth) oil analysis from Blackstone Lab (after 5K total miles and 4K of towing on the oil) was excellent. But the 5.4L had little to no reserve power, i.e. no acceleration for passing slower folks than me. It was so bad, I had to wait to be heading downhill to pass. Very frustrating. The best MPG I've seen on my Ford towing is nine and a skosh more, and that's up from about eight after I went to a K&N air filter (not the whole CAI kit) and did a "Zoodad mod" (increase "cool" air flow into the air filter snorkel by drilling a grid of holes in the plastic frame on the driver side of the radiator. about 12% improvement in towing MPG, about 25+% improvement in unloaded MPG on the highway.) My point? I'm glad to hear about the power of your diesel pulling your rig :bounce: but I'm "sad" to hear about your mileage :banghead: because our rigs are so similar. (My current TT may be a little lighter than your current rig, but with the increased power from my LMM, I'll be upgrading to something bigger and heavier in the future - ain't that what good Americans are supposed to do? Go bigger and better? Hell yeah! :saluteusa:

Anyway, let us know your future numbers. I hope they get better for ya. I've got a little under 200 to go on my initital break in. Once that's done, and I get my TT back from the dealer, I'll do a test tow (yeah, yeah, for 500 miles no more than 50 mph --- does anyone really tow that slow for the first 500 miles? I thought I'd go crazy for the first hour I did 60 with my Ford and Puma! :Pshyco:) and post the numbers.

Cheers ya'll.

Your numbers are pretty much in the same ballpark as mine. I'm not all that impressed with the mileage we're getting but, the towing power is everything that I thought it would be.

It's kind of odd to hear all the different mileage responses. Im not sure if they're embarassed to admit the accurate mileage or they just happened to travel in the direction of a tailwind everywhere they go?

We went out camping with a group this weekend and when we got to our destination, another of the diesel owners said he had enough fuel to get home without refilling. This is a guy that claims to get 20+ while towing. Saw him later that night filling the truck with fuel cans but I didn't say anything. For the life of me, I can't figure these people out that want others to believe that they have some miracle mileage truck?

makes no sense to me either...why not just be truthful with the mileage...i'm very impressed with the power of mine...just some short tows...nothing long yet...not until march...i'm looking forward to it...

After a 6000 mile road trip hauling a 39' Cardinal (around 15300lbs loaded), I averaged around 8.2MPG. Keeping in mind the trailer is roughly 12'9" tall, and I kept an air scoop on front, I don't think that's too bad. My former '04 Ram 3500 Short Bed averaged 9.2 MPG while towing the same fifth wheel earlier last year.

My speed was at 60-65 depending on how sparse traffic was, and it was ALL highway, hardly any stop and go at all (travelling across the wide open west). That included going through Virginia, Florida, West Texas, Arizona (yep, past the Grand Canyon), and into Las Vegas and back. So a wide variety of terrain and road conditions.

Favorite features are the integrated trailer brake and that great transmission. The "Grade Braking" feature is a little intense when driving down 7-8% grades with that much in tow - I turned it off since it kept downshifting to 4th and stayed at 3500RPM while going downhill. Jake Brake would be better, but that's Dodge. Otherwise, the shift schedule and the smooth 1-2 and 2-3 shifts are great while under tow. Being able to leave the vehicle in cruise while in tow/haul mode with no worries about erratic shifting down to 4th when hitting a small incline is also nice. Otherwise the ride was even and fairly smooth (maybe a little too much Cadillac bounce from the front suspension on the highway), enjoyed the Tahoe-like interior and the quiet ride.

Wish the turning radius was better, wish it could be equipped with a Jake Brake somehow and that they wouldn't put such piddly looking tires on a 3500HD truck. Otherwise I'm a happy hauler.

The Allison is sweet - nobody else has it - even when not in haul mode you can feel it brake for you. How about flipping to manual shift if you only want down a gear for braking?

;)

I won't be towing for a while so I'll see if it does better with mileage next time. All the diesel I bought came from South Carolina with the return trip on the coast so I didn't think winter blend would have been in play. Maybe the excessive wind and an 11 foot high trailer had the most to do with it.
ZeeMonster, I really enjoyed the Allison braking feature also. I hardly touched the brakes on most all stops and the integrated brake controller worked great. It really was a joy to have a vehicle that was made to do the job with ease.:)

Maybe I'm just jealous because I have a gasser, but how in the world are guys getting 20+ mpg empty with a HD diesel? All the stock D-Maxes I've been around get 15-17 empty. I've have heard of the early LB7's getting close to 20, but these were rated much lower hp. My father in law has had an LLY, LBZ, and now a brand new LMM. They've all got about the same mileage. So far he says the LMM isn't any better than the first LLY he had. But it's not broke in yet either. He averaged 15 on a 300 mile trip where he picked it up. I've gotten 16 mpg with my 6.0 once, but that was 65 mph, all interstate with a tailwind. Realistically it gets 12-13. I guess I'm not trying to call b.s. on anyone, but consistently getting 20+ mpg out of a 7000 lb truck is somewhat hard to believe, but I know there are alot of people out there who claim this so maybe it's possible.

Doodle, none of my neighbors, friends, or other folks I know have LMMs so I don't have anything to compare my mileage to.......except what I read here at DP.

Yeah, I'm one of "those guys" who gets 20+. As a matter of fact, I have seen 22 for just a little while on the highway going about 60-59. It didn't last long but it was not just a quickie, it lasted for a minute or so. More often than not, I get about 18+ doing 60.

I'm only one guy, and a newbie at that, but I ain't foolin' and I ain't braggin'. I got no need to. :coolio:

And as they say, YMMV.

Cheers.

Heck I have seen 99mpg on the DIC - you can too - reset your DIC right before you exit the freeway.....Weeeeeee......

I would have to get on the freeway full of fuel - 60mph cruise control in best of driving conditions - and fuel up as soon as I get off the freeway to show 22 hand calc. In the real world hand calc driving I did 19mpg best hand calc mostly freeway. Combo this week was 14.5 hand calc real world on winter fuel and mostly in town. Here's my records from the stealership floor day 1 to today:

Trip MPG
242 17 (18+ Hwy) Mostly Freeway
275 16
287 15
335* 17 New Wheels/Tires (1K miles)
158* 14
114* 14
172* 11.5 Towing
204* 17 Mostly Freeway
254* 17
256* 18 Mostly Freeway 7/07 Stanadyne (2K miles)
118* 15
90* 18 Mostly Freeway
269* 18 Mostly Freeway
289* 13 Towing
277* 14.5 8/07 (7 gal B99 BioDiesel) B5 (3K miles)
273* 18 (18+ Hwy) Mostly Freeway Canopy
287* 19 (19+ Hwy) Mostly Freeway B2
229* 14 (21+ Hwy) B5 (4K miles)
239* 15 B2
308* 18 (21.9 Hwy) Mostly Freeway B4
363* 18 Mostly Freeway B5
382* 18 Mostly Freeway B1 (5K miles)
225* 15 B0
273* 14.7 B4
235* 15 (21.5 Hwy) B5
236* 15 12/07 (6 gal B99) B3 (6K miles)
275* 14.5 B5

*5% correction added for bigger wheels/tires.

So I have averaged 16mpg in all driving conditions in 27 fill-ups. I will say one thing - any time a gasser new body owner talks trucks with me - invariably the first question out of his mouth is what's my MPG. I always say 22 freeway to shock them, then say 15 around town.

;)

Doodle, none of my neighbors, friends, or other folks I know have LMMs so I don't have anything to compare my mileage to.......except what I read here at DP.

Yeah, I'm one of "those guys" who gets 20+. As a matter of fact, I have seen 22 for just a little while on the highway going about 60-59. It didn't last long but it was not just a quickie, it lasted for a minute or so. More often than not, I get about 18+ doing 60.

I'm only one guy, and a newbie at that, but I ain't foolin' and I ain't braggin'. I got no need to. :coolio:

And as they say, YMMV.

Cheers.

All I'm getting at is yeah you can get 20+ mpg with a Diesel, but how many of us that have an HD pickup strictly run on the highway at 60-65 mph? Most of use use ours for work and play that envolves hauling/towing something. And I don't know about you but I don't ever drive 60, more like 75 or 80. There's no question the diesel beats my gasser in overall mileage, but what I have noticed is towing mileage isn't that much different from my 6.0 to a D-Max. There's one advantage though, the D-Max in tow will blow by my gasser!

Has the tow/haul mode changed in the Allison from the LLY to the LMM?

Has the tow/haul mode changed in the Allison from the LLY to the LMM?

Nope - Very little has changed under the sheet metal except emmissions.

:cool:

With you guys with the new LMM, how does it compare to the LBZ and LLY. My father-in-law says so far doesn't his LMM doesn't seem to have anymore power than his LLY. But it is brand new. I thought I read somewhere that the computer only allows the engine to operate at 70% power until it has run for so many hours. Have you heard of this? If that's the case it should just keep getting better with more miles.

Doodle, You are correct that with combined driving the mileage is different. However, straight driving on the interstate does allow a 20 mpg average. Terrain does play into the numbers, up a hill you lose a little, down a hill you gain some back. I have even driven behind an 18 wheeler, although not too close of course, and have picked up a few tenths.
65 or 70 didn't seem to matter much, maybe 55 would, I don't know.
What mileage have you gotten with your trailer in tow?

I have the LB7 ('03 Dually) and while empty, I average about 20 mpg (I currently have about 70,000 miles on my truck - 24,000 of it in the last 9 months since I bought it used).

When towing my 49' gooseneck with 18,000 lbs on it (making it just a hair under 28,000 lbs total) and my total weight just under 36,000 lbs with the truck, I average 10.75 mpg with OD turned off (tranny does a lot of fishing at that weight), but if the ground is flat and OD is enabled, I get about 13.5 mpg.

My truck is barely broken in and the numbers are looking really good.

By the way, on the west coast (oregon and california), I am only allowed to do 55 mph when hauling since I am commercial (apportioned). In Washington I can go 60 mph.

The only time I even see 65 mph is when not towing in the rural areas of Oregon, or up to 70 mph north of Vancouver WA towards Tacoma and not towing.

The Allison is sweet - nobody else has it - even when not in haul mode you can feel it brake for you. How about flipping to manual shift if you only want down a gear for braking?

;)

You won't feel it brake with 15k+ behind you on a grade. Even dropping 2 gears you'll gain way too much speed. Goin down the grapevine in L.A. I smell my brake's roasting while my buddy with his 6.7 Dodge and exhaust brake barely touch the brakes at all. An exhaust brake makes a HUGE difference....

I LOVE my Allison for towing compared to my 05 dodge. rarely have to use the brakes using tow/haul, granted i don't tow heavy but a big improvement over the dodge....and the choice to manual shift is great too!

I too have been surprised at the range of different MPG readings I get just out of my truck. This is my first Diesel and it seems much more sensitive to driving style and termperature than my gas truck.

We had a little cold snap here in Texas last week and I watched my mileage steadily drop from 18 down to 15 during the cold weather (driving around town unloaded). It has been warm the last few days and the mileage is back up to 17.5

For the most part, I track mileage by the tankfull. Like Jimmy said, you can see 99MPG if you reset the DIC and then coast down an exit ramp, but thats not reality.

You won't feel it brake with 15k+ behind you on a grade. Even dropping 2 gears you'll gain way too much speed. Goin down the grapevine in L.A. I smell my brake's roasting while my buddy with his 6.7 Dodge and exhaust brake barely touch the brakes at all. An exhaust brake makes a HUGE difference....

That's the truth! I wasn't too thrilled how the allison almost red lined either when decending a hill. It just detects the angle and if you even touch the brakes it downshifts. The dealer says don't worry about it because allison will take care of max, but I just don't like the sound of max screaming like that.

However, the exhaust brake makes a HUGE difference - even better than the Jake brake I had on an 18-wheeler with a CAT.