Im curious, I want to go to 32" tires on a 98 Sahara would I need to re-gear from the factory gears or is the power decrease not too bad to deal with. Im trying to make a final decision between 31's and 32's. I only do moderate off roading, no large rocks mostly mudd and sand due to living in Coastal NC.

Thanks!

When I went to 32's I wanted to regear, but it is not required. I am running 4.11 in mine right now, but the power loss is signifigant enough that I want to go to 4.88 but by no means is it required. I also have the 4 cyl.

Please fill out your profile so we can help a bit more...knowing the Eng./trany/x-fer would help, but as a rule of thumb I think all models can take 31's without any drive line problems. You'll prob. need some lift to fit them though. I know CJ's you can get 31's under without any mod, but YJ's do need some lift, and TJ's I'm not to sure about...

Hope that helps...
Tucker

I haven't tried it, but if the 30's that came stock are really 30's one could easily fit 31's and most likely not rub anything. That's .5 inch all the way around - not to insult anyone's intelligence, I'm just emphasizing..

I know some people who go up to 32-33 start looking at other engine performance mods rather than gears. New air intake can help, new exhaust etc..

You should be able to scavenge 20 horsepower or so from that and should minimize the .5 inch tire increase.

Those original tires currently? What kind of mileage did you get out of them?

-Bigscout79

Almost forgot I have several Engine mods, and it helps but did not solve the problems.

As for fit, 31's wil fit with only minor rubbing when stuffed. 32's you will need a lift.

That is my experience maybee other's differ.

I drive a 2003 TJ 4.0L, no lift, stock gears and have 31" BFG's. It has plenty of power without regearing and no rubbing even under articulation or a full turn. I did the same checking around before getting the tires and most told me 32"s would fit but rub slightly during a full turn and I would feel the power loss. The Jeep handles great off road and as a daily driver with the 31"s.

</font><blockquote><font class="small">In reply to:</font><hr />
but if the 30's that came stock are really 30's one could easily fit 31's and most likely not rub anything. That's .5 inch all the way around - not to insult anyone's intelligence, I'm just emphasizing..


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..but the 30" tires aren't 30" ..not even close. They are just about the same as 275/35r15 ..or about 28.5".

That being said ..the problem is not the height of the tire AT ALL. I put 33" tires on my wife's Sahara WITH NO LIFT. The only issue (beside it looking rather "bloated") is either the width (virtually anything having a section width over 9.50 ..or the diameter (in my case 33") causes rubbing at the extremes when steering. Naturally if you intend to flex much ....the height will be an issue ...but that's an issue with smaller tires as well.

Brent,
To answer your original question about gears...I would recomend it. That is assuming 2 things...4.0 and manual tranny. If you have an automatic, the torque converter does a good job of hiding the loss in performance.

As a rule of thumb, 32-33" tires should have 4.10 gears. 35" Should have 4.56 gears.

You can get by with stock gears, but gas mileage and performance will not be as good as they could.

I was running stock gears with 32" tires...then went to 4.10 gears. Night and day difference...especially on the trails. It's also a lot easier on the clutch.

My wife's cheorkee has 31" tires with stock gears. Gas mileage sucks right now because of this. She wants lockers and gears for xmas.