Bullitin#15097103 VS 210730034?

[pullinpower]

I have the 15097103 for the excessive shifting while in cruise and idle surge/

Well their seems to be a new # of 210730034 what are the diff.in the two updates? Going to take my truck in for the 2-1 shift down and was looking at these new #'s.

[ 04-28-2002: Message edited by: pullinpower ]</p>

[mark45678]

I cant seam to get mine fixed... I have been told by a good friend of mine that my truck has the lastest software! I still have the 2-1 down shift problem. slow to a stop on a steep hill and start moveing with out takeing your foot off the go peddle and bang it down shifting and blowing the drive line into small un-useable little pieces! I bet if there was like more then just a few bent up drive shafts or broken Allisons the problem would get solved really quick :D

[Billy14]

pullinpower & Mark45678,

I think I've posted this a half dozen times under "Late shift into 1st" & numerous other topics. Not certain, but I think I was the instigator of this problem. Bugged the hell out of me slamming into 1st on a grade holding the truck with throttle only. Dealer & GM said it was the 295 tires but I wouldn't buy it. :mad: Took the Service MGR. for a drive in an identical stock truck & did the same thing. :D :D Once again, here it is. Truck drops into 1st like a dream now & overall shifting is improved.

This is what my service invoice stated:

Cust states trans jerks into 1st on enclines when accelorating
TCM Misprogrammed
Reprogrammed TCM with updaded program
K5364 0.7

Billy

[ 04-28-2002: Message edited by: Billy14 ]</p>

[pullinpower]

Thx billy14,when I put my vin# in it gives me a differant # for the address of excessive shifting while in cruise.It does not list the 2-1 shift fix yet,does this new # address this issue or is it just a updated patch

[Billy14]

pullinpower,

I pulled out my invoice again to make sure. This patch was done 3/26/02. According to the dealer & confirmed by someone on this forum, the patch was released the previous Monday 3/18/02. They told me it was to address the downshift problem into first issue only. All I know for now.

(patch update K5364 0.7)

Billy

[odoh]

In reading this thread, I thot that I too should chk my coding at: http://vci.ecomm.gm.com/vci/

Unfortunately, I get a not found for my vin. In helps, it addresses older vehicles but not my new 02 D/A.

Any ideas/thots as to why? Perhaps it too recent and hasn't been added yet? ~ odoh

[midwest]

THESE NUMBERS ARE NOT GM BULLETIN NUMBERS THAT WE USE IN THE FIELD. YES THERE IS A BULLETIN FOR SHIFT BUSINESS WITH CRUISE AN ONE FOR 2-1 DOWNSHIFT.THE BEST WAY TO SEE IF YOU HAVE THE NEWEST SOFTWARE IS TO TAKE IT TO THE DEALER.THE INTERNET CALIBRATIONS ONLY TELL YOU WHAT IT WAS PRODUCED WITH. THE CALIBRATION FIXES THE CRUISE PROBLEM AND HELPS THE 2-1 DOWNSHIFT.THE TRANS WILL NOT MAKE THE 2-1 DOWNSHIFT TILL A COMPLETE STOP AND NO THROTTLE. IF YOU INSIST ON ROLLING STOPS OR HOLDING YOUR FOOT ON THE THROTTLE THIS WILL HAPPEN.THE BIGGEST PROBLEM WITH THIS TRANS IS THAT EVERYONE TRIES TO COMPARE IT TO A NORMAL TRANS,IT IS NOT. IT IS A HEAVY DUTY TRANS!AS FOR MAINTAINING POSITION ON A HILL AT A STOP, IF YOU USE THE BRAKE LIKE INTENDED AND REMOVE YOU FOOT FROM ACCEL IT WILL DOWNSHIFT TO FIRST.THEN IF YOU FEEL YOU HAVE TO HOLD YOUR POSITION WITH THE THROTTLE IT WON'T FORCE THE 2-1 DOWNSHIFT ON ACCEL. (IF IT HURTS WHEN I DO THIS THEN DON'T DO IT)

[hardwood]

Does anyone know the GM bulletin number for the PCM calibration applying to this 2-1 downshift problem for 2002's? I am taking my truck in to the dealer tomorrow, so they can check the PCM and TCM for the latest programming.

[Redhawk]

We don't have too many stop signs around here so a rolling stop doesn't happen too often, but when I approach my driveway, which is pretty steep and off camber, I have to slow down quite a bit, then when I give it some more throttle it sort of goes into neutral, revs up and then slams into gear before I can react. I don't care how tough this transmission and drive train is, it can't be too good for it. It doesn't do it very often but often enough to worry me.

Is this the 2-1 thing you all are talking about?

[Billy14]

midwest,

I promise, the TCM program I keep mentioning DOES solve the problem. On my truck & a friends.

Even with the BFG 295's I can pull onto a steep grade with the tranny in 3rd or 2nd & slow to a stop & hold the truck only using the throttle not applying any brake or backing off the throttle. Just before the truck comes to a complete stop the Allison will drop down into 1st while STILL holding throttle. I mean it. It shifts down, every time like a dream. The patch really works!

Here's what my service invoice states:
Cust states trans jerks into 1st on enclines when accelorating
TCM Misprogrammed
Reprogrammed TCM with updaded program
K5364 0.7

Billy

[Turbo Al]

There is more info on this in the emmmumm driveline forum under 2 to 1 shift.

[mcfly]

Just had it done. It works like a dream. I do now notice the 2 to 1 down shift kinda firm :D For those of you who are having the 2 to 1 down shift issue, DO IT Dam it! you will not be sorry.


-Rick

[mcfly]

Just had it done. It works like a dream. I do now notice the 2 to 1 down shift, kinda firm :D For those of you who are having the 2 to 1 down shift issue, DO IT Dam it! you will not be sorry.


-Rick

[ 04-29-2002: Message edited by: mcfly ]</p>

[midwest]

THE BULLETIN NUMBER FOR SHIFT BUSINESS WITH CRUISE IS 01-07-30-034 THE EASIEST WAY TO FIND IT IS BY DOCUMENT #826934CALIBRATION #15097103
I CAN'T FIND THE 2-1DOWNSHIFT BULLETIN BUT IT'S REAL SIMPLE FOR THE DEALER TO DO IF THEY GO INTO SERVICE PROGRAMING ON THE TECH 2 AND GET A DOWNLOAD OF VEHICLE.TAKE THIS INFO TO THE TECHLINE TERMINAL AND YOU WILL HAVE TO CHOOSE POWERTRAIN OR TRANS (AND SEVERAL OTHERS NOT IMPORTANT HERE) PICK TRANS AND IT WILL GIVE YOU THE NEWEST FILES AVAILABLE AND USUALLY THEY ARE ALLWAYS SUPERSEEDED(sp) TO THE NEWEST AND GREATEST.IF YOU TECH HAS HALF A BRAIN ITS HARD TO SCREW THIS UP. VERY SIMPLE AND EVERY DEALER SHOULD KNOW HOW TO DO THIS.YOU CAN ALSO HAVE THEM CHECK POWERTRAIN UPDATES WHILE YOUR THERE. I PERSONALLY WOULD INSTALL ALL THE LATEST SOFTWARE UPDATES.

[Turbo Al]

Mcfly that's great BUT what the heck did you have done??

[hardwood]

Just got back from a 800 mile road trip towing a load from Dayton OH to Sweetwater TN using the new and improved Allison/Duromax calibrations. The towing performance is considerably better. In particular, 5th gear holds better and downshifting is better matched to the power of the duromax.

During the trip, the truck would downshift, but much less frequently, thanks to the improved power transfer of the allison update. When the speed would drop &gt;4 mph in cruise, the truck would downshift as before. But when it did, watch out! The power rushed to the ground and the truck speeds up to 1 mph below the set speed and holds it until the allison senses you are over the hill. Then it upshifts and carries right on down the road like a diesel should. Jellico was no problem this time, unlike about a 2 months ago with the previous calibrations. Much improved performance - even Trussman would be impressed.

2 to 1 downshift is also improved and firmer shiftpoints are present.

I would note that Buckman is correct, that when the Allison TCM is calibrated, the PCM needs to be programmed concurrently.

It may also have helped that I hooked up to my trailer about 10 miles after picking up the truck at the dealer. I wanted it to learn fast... and the fast learn mode of the allison works great!

Thanks to Billy14 and others that have recommended the new calibrations. You will not regret it... now if they would come out with the overdrive lockout switch...

[freestates]

I had a TCM update done on May 1. I was not happy with the way the tranny downshifted at highway speed with the slightest depress of the accelerator pedal. The other concern was the "hill stop". Seemed like the tranny was confused and not sure if it should be in 1st or 2nd gear. The update addressed both issues. At highway speed the tranny holds 5th gear when passing and drops into 1st gear when stopping on a hill. This is how it went:
The technician hooked up the Tech 2 to my truck and downloaded my existing software into the Tech 2. He then proceeded to his computer to see if the existing programming was current. Everything was current with the exception of a TCM update. These are the updates that addressed my problems:

Service programming:
15175854-"new software to accomodate overdrive defeat switch and address 2-1 shift quality".

15175857-"new calibration to accomodate overdrive defeat switch and address 2-1 shift quality".

I am pleased with these new updates.


Wayne

[TBC]

I never had the 2-1 shift problem but the overdrive shift problem I did have it. I took it the dealer today and the reprogramed it. The service manager said it fixes 5 different things. It seems to accelerate faster and the shift is smoother. I could not believe the difference in acceleration and it was great before, even with a little throttle. It actually seems to have more power. I will find out about the towing issues at the end of the month on the way to the Grand Canyon and back with my 32ft TT.

[walkerkd]

tbc,
what dealer did you go to? and did you have to wait forever or were you in and out?

[pullinpower]

Well I stopped by the local dealer to try my luck with the computer reprograming for the 2-1 downshift and to my surprize they knew or at least acted like they did on the update and told me their tech could do it thursday morning while I waited :D That was good to hear since I thought I was going to get the runaround.Good job liberty chevrolet.

[pullinpower]

Oh yea I forgot to add that they didnt even look twice at my 285's that are on the truck now.hope when I get their thurs.that the tech doesnt try to give me any trouble on the updates.

[TBC]

I went to Classic Chev in Grapevine at about 8:15 and was out in about 30 minutes. I called them and set up the day. Great service.

[pullinpower]

Well TBC can you tell any differance in how the truck shifts?

[pullinpower]

I had the update done this a.m. and the tranny sure shifts firmer than it did before and seems to use the engines torque more.The tech and I both looked for any more updates and those 2 fro the tranny where the only one's avalible.So far I like the new program,gotta go and drive some more. :D

[TBC]

Pullinpower

Yes I did notice a big difference. I towed my 32 travel trailer Sat to get a state inspection and the overpasses that used to cause it to drop out of OD in cruise were taken without a hint of slowing down or dropping out.