Gear Swap Frt & Rear 1500 W/posi.

[sorel]

I want to change my gears from 3.73 to 4.10 or 4.56 (prefer 4.56) since i will be installing 285/70/17 tires, i want final drive ratio to be around 4.25. ?Can anybody shed any light on this? I Want to do the install myself, don't think it shold be too hard, since i have rebuilt engines and rebuilt automatic trannies. Any info as far as special tools or procedures required for the job would be helpful.

 

[simtechray]

Check this link for gear and drive ratios calculators.
Doing a gear swap does require special tools to set it up properly, not something I'd recommend but good luck.

 

[Butch]

It gets pretty involved..., I did mine at my friends transmission shop as he does gears all the time.., it took us 6 hours to get the rear set up right.., you need a 0-400 ft/lb torque wench to torque the pinion nut.., and you'll also need a pinion depth gauge to set the pinion depth correctly.., the front diff is a real bear to do.., and has to be removed from the truck to do it... Since I have the Supercharger.., I installed an Eaton Heavy Duty Posi unit at the same time.... If you plan on upping the horse power, or using your truck off road its something you might want to consider..., as its not that much more money to do if your going to be swapping gears...... I also had Randys Ring and Pinion build me a Heavy Duty front differential for mine..., and just swapped out the front diff.., and sent them mine back as a core...., cuts down on the time a lot..., as it only took an hour and a half to swap out the front diff..., verses removing it, disassembling it, and swapping the gears out..., and reinstalling it.., just something to think about.......

Butch.

 

[steelheadchaser]

Too bad GM doesn't go with some of the drop-out pumpkins on the diffs like brand X and Y have used in the past. You could have your cake and eat it too as far as ratios and locker types.