ive got a 94 gmc jimmy, 2dr 4x4. im putting in a rebuilt 4l60e with a shift kit in it very soon, but im wanting to know what are the differential gear ratios and if i can change them up to 4:10s, is this possible and will this help towing? and are there limited slip diffs with 4:10 gearing, like a diff kit so i just have to rebuild that and not swap for a different axel
some questions?
- Thread starter dmd1125
- Start date
Molson02536
New member
Don't change the rear end, may be replace it with a limited slip. The 4L60E has a low first gear anyways and try to stay way from a shift kit on your Jimmy.
There are issues with shift kits with the PCM programed in your Jimmy and sice it's a OBD1 system. The chip needs to be custom burned to match the performance your looking for.
The Cam in your 4.3 works it's best in the low and mid rpm and nothing really in the high rpm range. The lower the gears will cause your engine to be in the higher RPM range where the 4.3 is not it's best for TQ.
As for the transmission, just replace the servo with corvette servo, replace the boost valve and sleeve with a 0.490", remove and discard the 3/4 load release spring assemblies (5 small rectangular spring assemblies installed into the input housing, on the outside of the clutch pack). This really improves the 2-3 shift.
Good luck and keep us posted
Molson02536
New member
Salvage yard or a local transmission shop (drive line) shop can get a new one in for you a rebuilt one. Just call around your local area shops.
Good luck and keep us posted.