What gear Ratio is best?

[Tdean91491]

Alright guy’s I’ve been debating on pulling the rear axle and the front differential off of one of my parts trucks, replacing all the bearings and seals & regearing them. I’m running 35’s and plan to keep running them. What ratio would benefit the most?

 

[PlayingWithTBI]

What are your gears now? Do you want more performance or mileage? For 35" tires, I would think 4.10 or 4.56 ratio.

 

[grampadirt]

4.56,it's what I have.Drives well,pulls well.Of course with the 7.4l fuel mileage ain't the best lol.

 

[96dually454]

I have 4.10 in my 89 8-lug 2500 with the SM465 it pulls really well.

Also have 4.10 in my 96 K3500 Dually with the 454/4L80E combo I get at best 10.5 MPG if I keep my foot out of it.

 

[Tdean91491]

What are your gears now? Do you want more performance or mileage? For 35" tires, I would think 4.10 or 4.56 ratio.

I haven’t opened anything up but from the rpo codes it has 3.62. Ive never attempted a rear end rebuild, I’ve been doing some research & it seems to be simple if you have common sense & follow directions. I’m probably going to go ahead and pull the rear end out from under the parts truck & set it on some stands in the shop. Start getting the parts together & attempt it. Do you guys have any recommendations on a kit or carrier?

 

[Tdean91491]

4.56,it's what I have.Drives well,pulls well.Of course with the 7.4l fuel mileage ain't the best lol.

Mines just a 1500 with the 5.7.

 

[df2x4]

I haven’t opened anything up but from the rpo codes it has 3.62.

You mean 3.42? Pretty sure 3.62 wasn't an option.

 

[Tdean91491]

Let me double check. I think your right though.

 

[Tdean91491]

I just double checked and you are right, thanks for correcting me on that.

 

[c1500deathtrap]

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