Gear ratio help

[Jwebb01]

I have dana 30/35 factory 3:07 gears and 33” tires with 4” lift. I have the 3 speed auto trans. The current gear ratio is bad. What would be a good gear ratio to run with the set up i have?

 

[TheBoogieman]

4.10 with the 3 speed auto. 4.56 if you live in the mountains and don't drive over 65 mph. I swapped in some 4 cylinder Jeep axles with 4.10s in my old Jeep with 33s and a 32rh trans. Worked very well. I also used 4.56s with 32s. Too high rpms on the highway for me.

 

[pagrey]

@Chris has a great write up on this, any reason your setup is special?

 

[Jwebb01]

@Chris has a great write up on this, any reason your setup is special?

What do you mean by “special “ ?

4.10 with the 3 speed auto. 4.56 if you live in the mountains and don't drive over 65 mph. I swapped in some 4 cylinder Jeep axles with 4.10s in my old Jeep with 33s and a 32rh trans. Worked very well. I also used 4.56s with 32s. Too high rpms on the highway for me.

I do live in the mountains. And with the 3.07s i feel like im really lacking power. I do drive on the highway sometimes but also wheel so i am trying to find the gear ratio that would work best for both

 

[pagrey]

What do you mean

Sounds like the normal recommendations would suit you fine. Sometimes people start a thread because they have something different about their rigs that makes them second guess the normal advice.

 

[Jwebb01]

Oh no nothing special here. Just looking for advice. Figured starting a thread would be the best way

 

[jjvw]

4.10 with the 3 speed auto. 4.56 if you live in the mountains and don't drive over 65 mph. I swapped in some 4 cylinder Jeep axles with 4.10s in my old Jeep with 33s and a 32rh trans. Worked very well. I also used 4.56s with 32s. Too high rpms on the highway for me.

4.56 feels really high for 33s. I would do 3.73.

32rh/32"/3.73=2937rpm @ 75mph
32rh/32"/4.10=3229rpm @ 75mph

 

[mrblaine]

4.56 feels really high for 33s. I would do 3.73.

32rh/32"/3.73=2937rpm @ 75mph
32rh/32"/4.10=3229rpm @ 75mph

Stock is 3.73 for 30ish" tires. You now have him worse than stock.

 

[machoheadgames]

I’d go 4.10. The factory shipped plenty of the 3-speeds on 28-30” tires with 3.73 and they revved higher than most all other vehicles. It’s no big deal, just the nature of a 3-speed auto.