I own a 04 with a stock LB7 4WD, extended cab, long bed.

At work we have an 06 3500 LBZ and a Powerstorke.

The power is really noticeably lower than the LBZ 3500 and the Powerstroke F350 trucks.

From a dead stop, engine up to temperature on a flat blacktop road, the truck will NOT spin nor offer to spin the rears when floored. Our LBZ truck (dual rear wheels) will bark when punched and the Ford will light them up (single rear tire).

Now, I'm pulling a 22' 3 axle gooseneck trailer. With around 9,000 Lb on the trailer, the truck struggles to get up to 70 MPH (flat from dead stop, maybe 1 mile to get to 70 MPH) Up even a slight incline, downshifts and engine is flirting with redline to keep speed. Cruising 70 MPH interstate flat, punching it, it downshifts, near redlines and accelerates very slowly. Up a moderately steep incline (interstate), truck falls back to 40 - 45 MPH floored.

Does this seem right to you or is this truck typical of the stock LB7's ?

I run Kiesel Kleen every tank and change the fuel filter at every oil change. Truck has had this power since I got it (45K miles used).

No SES lights, no smoke, no rattling, just seems weak to me opposed to our Comnpany LBZ and our Ford Powerstroke. Mileage empty on interstate @ 70 is around 18 MPG. Pulling, I got 12 MPG. Temperatures (tranny - engine) pulling are normal.

Maybe I'm expecting more than I should from this older design engine ?

Any opinions are really appreciated.

M

sounds exactly like my truck... If you can get your hands on a scanner it would be nice so you can see any trouble codes that might be present. Does it surge at idle at all? It could either be your FPR or injector pump.

It surges when really cold but clears up when it warms up.

GM, by the way, told me I was nuts when I told them I thought it was weak on power. Checked codes and found none last oil - fuel filter change.

I really don't want to put a tuner in, I would hate to hose up my remaining warranty.

get the injector return rates check at ta dealer.


if they are above spec they will give a week cp3 pump sypmton

I agree, get someone with a tech2 to run some fuel system diagnostics.

when was the fuel filter last changed? could be all used up, and not allowing enough fuel through.

Ken

I own a 04 with a stock LB7 4WD, extended cab, long bed.

At work we have an 06 3500 LBZ and a Powerstorke.

The power is really noticeably lower than the LBZ 3500 and the Powerstroke F350 trucks.

I'm pulling a 22' 3 axle gooseneck trailer. With around 9,000 Lb on the trailer, the truck struggles to get up to 70 MPH (flat from dead stop, maybe 1 mile to get to 70 MPH) Up even a slight incline, downshifts and engine is flirting with redline to keep speed. Cruising 70 MPH interstate flat, punching it, it downshifts, near redlines and accelerates very slowly. Up a moderately steep incline (interstate), truck falls back to 40 - 45 MPH floored.

Does this seem right to you or is this truck typical of the stock LB7's ?

Maybe I'm expecting more than I should from this older design engine ?



I also have the LB7 with 93K miles and pull a 9K lb trailer. Took it out west two years ago going up the Rockies and in California the Grapevine and had no trouble going 70 up any mountain that didn't have corners that slowed me down. My biggest problem was watching out for the CHP in the rear view and keeping my eyes on the traffic in front of me. Get it checked.

I change fuel filters at every oil change. Last filter was about 1500 miles ago.

did you buy the truck new or used? has it always felt like this? i realize that you may not have been towing the goose from day one, but im sure you would have noticed maybe the power was just a little off? im just throwing it out there.

Ken

I got the truck at 42K miles used. I ran a VIN check and had no issues.

The truck has been steady power wise since day one. On the way home, I have an uphill interstate entrance ramp and I check it from time to time by punching it from the light and notice the speed when I run out of ramp.. it has been consistent.

At work we have a 06 LBZ 3500 dually 4WD with a service body - welder. We pull a bumper hitch trailer (dual axle). With the same load (around 9,000 lbs) it is WAY, WAY stronger.

Maybe all the LB7's are noticeably weaker than the LBZ or older Powerstrokes?

are the gear ratio's the same in the 3500 as the 2500? I believe the one ton's could have the 4.10 gear ratio's. the LB7 makes 520ft lbs torque and the LBZ makes 600ftlbs, I think, but have the injectors checked.

I don't think you can get 4.10's with the Duramax. I think you could have gotten that with the 8.1 gasser. I think all we could get was 3.73.

I'm tryin to figure out the same problem with my truck.
Even with a program same thing :eek:

the lbz has about 50 more hp and 130 more tq than teh lb7. both should have 3.73's

I can pull 10k with my 03 up to 70 with no problems at all.

However, I don't have a 1-1 comparison with the ford or new chev's either .

jb

if u get a tuner u can read the codes and see what they are if any and then juice it up some and ull wish u did it a long time ago

Winter bled fuel will decrease your power and your tire size will make a differance. I notice a power loss with 265 M/Ts vs. the stock pizza cutters.

My 04 lb7 regular cab has plenty of power even when it was stock. My dad has a 05 powerstroke and stock for stock it was very comparable. Wish I had more input then that but I just got the truck.

I own a 04 with a stock LB7 4WD, extended cab, long bed.

At work we have an 06 3500 LBZ and a Powerstorke.

The power is really noticeably lower than the LBZ 3500 and the Powerstroke F350 trucks.

From a dead stop, engine up to temperature on a flat blacktop road, the truck will NOT spin nor offer to spin the rears when floored. Our LBZ truck (dual rear wheels) will bark when punched and the Ford will light them up (single rear tire).

Now, I'm pulling a 22' 3 axle gooseneck trailer. With around 9,000 Lb on the trailer, the truck struggles to get up to 70 MPH (flat from dead stop, maybe 1 mile to get to 70 MPH) Up even a slight incline, downshifts and engine is flirting with redline to keep speed. Cruising 70 MPH interstate flat, punching it, it downshifts, near redlines and accelerates very slowly. Up a moderately steep incline (interstate), truck falls back to 40 - 45 MPH floored.

Does this seem right to you or is this truck typical of the stock LB7's ?

I run Kiesel Kleen every tank and change the fuel filter at every oil change. Truck has had this power since I got it (45K miles used).

No SES lights, no smoke, no rattling, just seems weak to me opposed to our Comnpany LBZ and our Ford Powerstroke. Mileage empty on interstate @ 70 is around 18 MPG. Pulling, I got 12 MPG. Temperatures (tranny - engine) pulling are normal.

Maybe I'm expecting more than I should from this older design engine ?

Any opinions are really appreciated.

M


My truck is exactly the same. Has your exhaust been modified?
If I floor mine from a dead stop it will not break loose the tires at all, as a matter of fact it takes off slower than if I were to take off normal, then when it shifts into 2nd gear get on it. I believe this is due to the torgue management from the TCM (transmission control module) These engines have a tremendose amount of torque,so to prevent any damages to the transmission or any other part of the drive train the output power is reduced. Also if your exhaust has been modified then spool up time on your turbo may be lagging. The only way my truck will turn the back tires on payment is; I hold the brake, bring the RPM's up a little to spool up the turbo then release the brake and floor it.

I don't think you can get 4.10's with the Duramax. I think you could have gotten that with the 8.1 gasser. I think all we could get was 3.73.
2500HD got the 3.73
3500HD got the 4.10

I have close to 1k lbs in the bed of my truck, she is stock and I can spank alot of ricers from red light to red light, I used to spin the tires until I got loaded down, but she is still fast

My 03 in stock form on dry pavement wont spin unless you rev it up . The power stock isnt bad but with the edge on level 2 on up the difference is stunning as many v8 mustangs have had their front ends covered with my smoke . It tows on level 2 really well a 30 ft travel trailer up 7% grades never losing speed on cruse control . I would have to say something is wrong thats why it had 45 k on it as mine has 47 k and it is strong . Rich

I just purchased my 03 a couple months ago and compared to an 07 I drove there was not comparison in power. I recently put an edge juice with attitude on with exhaust and there was a huge difference in power. I just hope the tranny hangs in there.

Both torque and HP on an LB7 are very noticeably lower that a LBZ. I run my Edge/Attitude on level 1, which is a better tune for fuel econony, and still make a very noticeable difference in performance.

On Level 1, HP is supposedly increased by approx 40 HP and 150 fp tq. At approx 340 HP and 670 fp, that makes my LB7 pretty close to the output of the LBZ.

All you have to remember is that it is not a race car. It is a work truck (you made it sound like it anyway).

most Powerchoke have 4.10 rear gears which makes a big difference. Torque management and tire size keep my tires from smoking ...

I know mine wasnt impressive until it was programmed by PPE :) Kinda sounds fuel related though, no smoke so its getting air. Have you ever cut open one of your filters. you could have crud in your tank that plugs them up quick

gotta remember too... the lly/lbz/lmm all vvt turbos. this allows them to build power MUCH faster in stock form off of idle than the lb7. mine will not spin the tires outa of first from idle in stock form. however, it is now wearing a programmer and i can light em up all the way through 2nd with the truck weighin in at over 10k lbs. :D

programmers will do wonders for these trucks but in stock form, the lack of vvt is what kills "out the hole" pedal response. the power is there, the response isnt....

When is the last time you changed the air filter?

My lb7 with the edge will emit a cloud of smoke and come out of the hole like a bandit if i move the response to level 5 , thats the response not the power level . I run it at level 3 response as i dont want the tires breaking loose and level 5 is just too touchy on the pedel . When its wet or icy out breaking the rear tires loose with a locker rear end in traffic is not a good thing . Rich

I haul my 70 Chevelle to the track with my LB7 (with trailer approx. 3700 lbs) and i never have trouble getting up to speed. I know thats no where near 9000 lbs like you were hauling but on flat ground my stock lb7 has no problem breaking the back tires loose.

What size tires are you running? That makes a big difference.

programmers will do wonders for these trucks but in stock form, the lack of vvt is what kills "out the hole" pedal response. the power is there, the response isnt....

"turbo gives you action, lag gives you traction."

Ken

"turbo gives you action, lag gives you traction."

Ken
If you are spinning, you are not going forward. Why don't you guys have yourselves a little race, just to see what happens;). Just be careful where you do the racing. Dragstrip would be ideal.

I have always felt the same about mine. I think it tows hard pulling my 8,000 lb camper. And I have been thru it all. Recently switched to PPE from my Edge and still think the 220 hp level should have more ump to it(although it is more than the Edge). I just don't get it, woulda thought it woulda pulled the camper like it wasn't even back there. Had to put Edge in level 3 to pull the thing around. For the hell of it I would drop it back to stock while driving and it felt like I was driving against a 100 mph head wind.

...For the hell of it I would drop it back to stock while driving and it felt like I was driving against a 100 mph head wind.


yeah, i get that feeling too when it goes back to stock. its wierd how you get used to the power from the programmer, then go back to stock. ive forgotten what my truck feels like stock, so i really have no baseline to go by if it feels like it lacks of power

Ken

That is so strange, I only get that feeling with my stock truck when going up hills. On level ground it tows my heavy ass trailer like it isn't there (well, it feels there, but you know what I mean... right?).