Northern Explorer
Explorer
I’ve decided that my next upgrade is to have my truck regeared to 4:10.1 The truck came stock with 3.43.1 with tires measuring 28.9 inches (235/75 15). I now have 31.7 inch tires (265/75 16 BFG AT). This puts my gearing about 9% off (to high) from stock. I have noticed that with this setup the truck will gear down a lot in search of power. The rpms stay higher longer and my gas mileage has gone down. I would like to upgrade my summer tires to 33.3 inch (255/85 16 BFG MT). If I go with this tire and the 4:10.1 gearing I will be about 4% off (to low). 4% is probably tolerable but if I decide to put my 265/75 16 back on for winter with the 4:10.1 I will again be off by about 9% (to low).
My questions are:
Is taking the truck to the dealer the only way to adjust the shift points on an automatic transmission?
Is there a reasonably priced device that you can adjust the shift points yourself?
What exactly needs to be adjusted and what do you tell the dealer?
And finally…nothing to do with gearing but do the anti lock breaks need to be adjusted when you switch to larger tires?
Any help would be great. I know nothing about this subject.
My questions are:
Is taking the truck to the dealer the only way to adjust the shift points on an automatic transmission?
Is there a reasonably priced device that you can adjust the shift points yourself?
What exactly needs to be adjusted and what do you tell the dealer?
And finally…nothing to do with gearing but do the anti lock breaks need to be adjusted when you switch to larger tires?
Any help would be great. I know nothing about this subject.
Last edited:
. Only the Colorado Sport. Not even sure if there would be a difference. I could just be blind. I will probably end up just going with the gear and tire change and seeing how it feels.