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I have a 2003 Tahoe. I'm not sure what the gear ratio is. I swapped the differential once so RPO codes are no use. The original code is GT4. The donor car is long gone. It's on 32" tires. I want to use bluecat to tune the transmission. What could the gear ratio be?
I raised the rear end and rotated the tire to try to identify the ratio. For two tire rotations the drive shaft turned about 2 1/2 or 2 3/4 times. I think this means the ratio is 2.xx something ish.
The transmission is 4l60e.
Just pull the cover and get it over with, count the teeth or read the markings on the ring gear.
I think you'll want to re-try that and see what your results are.
The Tahoe axle would have 3.23, 3.42 or 3.73's as far as I know from the factory.
If you have a G80 rear axle, do it really slow and only have 1 wheel off the ground. You don't want the locker to engage while you spin it.
I will need to do this, just haven't had the time. Thanks.Quote:
Originally Posted by blindsquirrel
Thanks for the quick response. I wasn't confident I did it right. I'm just going to make time and pull the cover. I've had transmission problems before and I think the trans tune is part of the problem.
I just jack up the rear put a zip tie on the driveshaft and have two people make exactly one full revolution of the tire and count how many times the driveshaft rotates. Takes under 5 minutes if you are slow