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dfe1
March 22nd, 2005, 02:03 PM
Has anybody done any tuning on a Hummer H2? I just started working on one and when I took it out for an initial test drive, I noticed that the shifting is extremely sloppy. It's almost as if each gear change is made in two stages and it literally takes 1-1/2 to 2 seconds for an upshift to take place. The shift takes noticeably more time to complete than in the Silverados/Sierras I've worked on. I'm just wondering if this is a normal H2 shift cal or if this particular vehicle has a trans problem.

87gmc
April 3rd, 2005, 12:05 PM
sounds like my Z71 :?

dfe1
April 3rd, 2005, 02:10 PM
I've been doing some research and some of the shift problems may be (at least to some degree) a result of the adaptive transmission data. I'll post more if I find a "cure".

wait4me
April 4th, 2005, 03:12 AM
if you send me that h2 file ill give you something to try :) jes

87gmc
April 4th, 2005, 06:01 AM
hey wait4me your leaving me out


Can you answer me though waht do you think is effecting the shifts.

dfe1
April 5th, 2005, 12:23 PM
I have a few more things to try, but I'm beginning to think that it's going to take a mechanical adjustment to bring the shifting around. The shift table in a 2002 Silverado I did is very similar to the one I did for the H2, yet the shift quality is completely different. I'm going to try the change that wait4me recommends, then reset the transmission adaptive data and see if that makes any significat change. I'll post what I find.

wait4me
April 5th, 2005, 02:37 PM
send the files to jessebubb@yahoo.com ill check them out. jes

GMPX
April 8th, 2005, 10:18 PM
Change the desired shift times to '0'. Then there should be no adaptive learning.
Have you read the adapt values in the scantool?.

Cheers,
Ross

dfe1
April 16th, 2005, 03:17 AM
Haven't had a chance to work with the vehicle again-- the owner has been out of town. By the way wait4me, have you had a chance to look over the file I sent?