Tire size

[xj805]

I have a 1991 xj with the 4.0 high output and was wondering if I ran 33"s if I would have to regear to maintain power?

[bigjim350]

To keep the same power yes. But its still drivable if you don't re-gear. Mine is driven almost daily on 33's with stock gears, does fine.

Sent from my nerdy smartphone

[Rustbucket]

I drove one of my jeeps with that setup for while. Driving on the highway and uphill wasn't fun but it still got me to work every day.

[xj805]

Thank a lot guys. Also I was wondering, I'm about to throw a 3" lift on my jeep and was wondering if I need new upper arms as well as lowers? And what's some good inexpensive lower arms?

[Carves]

Just in case it helps .....


Tyre & Diff Ratio Chart: .... http://www.jeep4x4center.com/jeep-tires/tire-gear-ratio-chart.htm

Dont forget the above revs are based on 1:1 ratio ... so O/D gives you a little leeway for highway speeds/revs.


Gearbox Ratios:

.......... AW4 ..... AX15 ..... AX 5

1........ 2.804 .... 3.83 ...... 3.93
2........ 1.531 .... 2.33 ...... 2.33
3........ 1.000 .... 1.44 ...... 1.45
4..................... 1.00 ...... 1.00
OD....... 0.753 ... 0.79 ...... 0.85

REV...... 2.393 ... 4.22 ...... 4.74

[4.3LXJ]

You can do a 3" lift without changing links if you want. But just lowers are fine

[denverd1]

as other have said, only time you will notice your gears are week is climbing hills and passing ppl at 70 mph. any bigger than 33 and I would want deeper gears, but 33 is manageable. enjoy your larger tires

[TimmyTXJ]

Thank a lot guys. Also I was wondering, I'm about to throw a 3" lift on my jeep and was wondering if I need new upper arms as well as lowers? And what's some good inexpensive lower arms?

I'd say it depends on your build philosophy. I have a 3" lift on my XJ and I replaced both the uppers and lowers but I'm planning to abuse it a little. At the very least, you might consider boxing the stock stamped arms for some extra strength. Both upper and lower OEMs were folded in on my Jeep.