[DetR6oit]

I wanted to avoid posting another stupid gear choice question here at all costs but I can't make up my mind becasue of so many other factors.


I have a TJ with the 2.5, AX-5, and will be running 40" tires and it does still get driven on the street and is not trailered yet. Using this gear setup calculator I am really liking how 6.17s will be just slightly lower than what it was stock. Stock was about 70mph at 3K rpm and the calculator says it will be 68mph at 3k. I don't have to worry too much about the 6.17 pinion strength either with the 2.5 and 60 front, 70 rear. Though even when I searched it looked like people didn't worry about its strength much anyway. But obviously the 4 banger won't be staying in there forever. Will that gearing be way too low with a V8? Will 5.86s still be too low for a V8? Was thinking 4.7 from a WJ possibly later on. And guessing that I will run an NV3550 behind it, that gear calculator says 61mph at 2500rpm



Or should I just say fawk it and make my goal, trailoring it by the time I do a new drivetrain, though thats would be fairly tough. I guess it can't stay street driveable forever........



Oh, and in before 4 bangler tells me the I should keep the 4 cyllinder and not worry about it

 

[sw99]

Go with the NV4500, 5.38's and call it a day! Yes,
doing gears for the 4 banger is totally gay! Just wait till you can do it right..

 

[Scott Mac.]

Always go one step lower that what you originaly thought would work nicely. No regrets.

 

[KCjeeper]

I would like to see that.....70mph on 40's with the 2.5! Maybe downhill.....

BTW Scott Mac....you have your priorities all screwed up. Wives come and go, but work, wheeling and wrenching will always be around.

 

[DetR6oit]

anymore opinions?

 

[apeters89]

I think you'd blow up that AX-5 before you ever had to worry about highway speeds. I'd just wait to do it all the right way. Get you a daily driver before you try to run 40's on your Jeep. JMHO...:flipoff2:

 

[apeters89]

I think you'd blow up that AX-5 before you ever had to worry about highway speeds. I'd just wait to do it all the right way. Get you a daily driver before you try to run 40's on your Jeep. JMHO...:flipoff2:

 

[TexasBlake]

One thing you are forgetting is that it's more than gear to pull those HUGE tires. YOu have to figure the weight and wind resistance, which you can't do with a calculator. I have problems pulling 33s down the road with 4.56s and the automatic. According to the calculator, I have enough gear to pull 36s, but I'm lacking power so it doesn't happen. But like said before, I would not plan on going highways speeds on 40s. But, everything goes you way, I would like to see it!

 

[4Bangler]

Keep the 4cyl.

If you're set on a manual, you can drop the big buck and go with the NV4500, but with 40's I really doubt you'll be seeing much freeway speed anyway, and an SM420 is a nice short package with a 7.05:1 1st that really helps the 4cyl get the rig rolling. If you don't mind and auto, a 700R4 would be a nice choice, but drivetrain lenght needs to be considered.

Bigdude runs a 4cyl with the stock auto and 38's on a 60/14 combo with 5.13's, but he's got that "small man syndrome" to help him overcome any lack of gearing.

 

[TexasBlake]

Bigdude runs a 4cyl with the stock auto and 38's on a 60/14 combo with 5.13's, but he's got that "small man syndrome" to help him overcome any lack of gearing.

True, but I don't think his can go over 45mph.

 

[Robert]

Wives come and go, but work, wheeling and wrenching will always be around.

I have to remember that for a future sig line.

 

[Robert]

Keep the 4cyl.

If you're set on a manual, you can drop the big buck and go with the NV4500, but with 40's I really doubt you'll be seeing much freeway speed anyway, and an SM420 is a nice short package with a 7.05:1 1st that really helps the 4cyl get the rig rolling. If you don't mind and auto, a 700R4 would be a nice choice, but drivetrain lenght needs to be considered.

That was what I was going to recomend. A four speed with a granny gear would be a better swap than ultra low axle gears.
You are going to destroy the AX-5 anyway.