IS THIS NORMAL? 05 hard tranny accelerating.

[Cliffee]

I ve had my 05 D/A for about 3 weeks and ive noticed that when cruising at low speeds in traffic and so, that when I coast and then give it gas the rpm's go up to about 12-1400 and then the truck starts accelerating but with a hard joilt. Its like it engages too solidly. It does it mostly in 1st and 2nd gear. 3rd and up are nice and smooth. My 03 did not do this at all. I called my loacal service manager and he said this was normal since they had to increase the tranny strength for the new engine.
Anyone experience this?

[4diesels]

I'm not so sure I would buy what the service manager is telling you. Unless something changed, the D-max is limited to the old 520 lb/ft in first and fifth because the Alli can't handle it. Does anybody know if they actually did beef up the tranny? I still don't think that it should shift hard even if they changed something.

[Dewey Faircloth]

Mine shifts fine.

[Cliffee]

Its not a shifting problem. Lets say I'm coasting (No accelerator) around 15 mph and the tranny is in second gear, when I first push down on the pedal the rpm's come up (12-1400rpm)and then the truck starts accelerating. The only thing is before I start accelerating when the tranny/torque converter locks up its rather hard. Its noticable in 2nd and a little in 3rd. 4th 5th are fine. Like I stated earlier my 03 was much smoother at lock up and I'm a bit concerned.

Thanks in advance!

[Rick_R_04LLY]

Have the same issue with the 04 hi output. Roughly 800 rpm drop when decelerating, then it winds up and slams into gear (harder if I get on it). Not only is it uncomfortable but seems like it will play heck on the drive train over time.

Also seems inconsistent when shifting at low speeds.

Any feedback or ideas? Can this be corrected in the computer?

[Cliffee]

Spoke to 2nd Service manager at a different dealer and he also explained that this is normal but not right. He felt that it shouldn't be there but it is and there's nothing to be worried about. Maybe it will be addressed in a later update?

[Mike in NJ]

My '04 does this also.

[Cornell]

My 04 LLY also does it. :rolleyes:

[mark45678]

the 2004.5 lly trucks have differnt software in the TCM then the older lb7 truck, they dont act the exact same ... 1st and 5th gear are down on power !

[More Power]

The symptoms you're reporting are not normal. I doubt GM would ever purposely allow an annoying driveability issue like this to be normal.

Visit your dealership's service writer. Explain that you're there for a warranty driveability issue. "Suggest" that the ECM/TCM may need to be reprogrammed with the newest program updates. Your can visit the ECM/TCM Update information link (http://vci.ecomm.gm.com/vci/) to see for yourself what updates are available for your VIN. Print them and take the update sheet with you when you visit the dealership

FYI - The LB7 doesn't make 300/520 in 1st either. ;)

As far as "the Allison not able to handle it".... We know a stock Allison behind an LB7 can handle somewhere in the vicinity of 400/750 before slippage occurs. Pulling fuel in 1st is more for improved driveability and longterm chassis/drivetrain durability.

MP