high-octane

hey guys! im new here. great sight. have a quesion. how bad would 33x12.5 be in a 08 x with 3.21 gears and a auto. i had 32's on my 4 cyn tj with a stick and never used 5th. would it be any better? i want the 33's but i want to be able to keep up with traffic too. thanks.

pearl-drum-man

WHat tires do you have now? You'll get a lot of variable opinions on this as it is somewhat subjective. I have the 4.10's with the stock 32" tires and I think it is just adequate (auto trans). Also, try a search and you'll get a ton of threads on this and get to see many more replies.

high-octane

I have the stock 225's now. They are just to small. Thanks for the quick reply.

TEEJ

The JK has a lot more torque - 32's are standard...going to 33's should not be that big a difference...and besides, using the next lower gear on my TJ was not that big a deal either...as far as the jeep knew, it was still driving the same rpm at the same speed....it doesn't matter if the gearing is metal or rubber, the true final drive in at that speed remains the same, you're just in a different gear shifter number.

Think of the big tires as a deeper over drive.

Cliff2004t

I have an 08 with 3.73 gears and auto trans. I think the 3.21 gears are only on the manual trans models.

I have 33x12.5 Dick Cepeks. There is plenty of power except when I am going
over 70 on the interstate. The overdrive will kick in and out. I have learned
to drive with the overdrive "off" all the time. I can then keep up with the fast
lane at 80 mph no problem and I still get 15 mpg fuel mileage.

pearl-drum-man

Since he has the 225's going to 33's will be a noticeable difference, whether it is acceptable to him is again subjective. As you say though, nothing a little downshift can't remedy.

bOLsAK=3

If you plan on staying w/33" tires for a while, I suggest 4.88 gearing. Besides, if you ever wanted to get 35" then you'd still be able to tolerate without having to change again. Also be mindful of other peoples responses with this subject because the 6speed and the 4speed automatic are two very different beasts and most people will comment on the auto without having driven it daily. You'll find that the people who actually own the auto have a different outlook on gearing.

I have to agree. I have had my stock 4.10's since I bought mine. I've complained numerous times about how low the RPM's were and that was with stock 32" tires (18"wheels). Now that I have 35"s the final gear is barely even useful, much less used. At 65mph (clocked) my RPM's are only at 1800. If anything, like I said, I agree with the comment above that the 4.10's w/32"s "is just adequate" with the auto. 4.88 gears would have been a nice upgrade. Now, with 35"s I'm currently searching for 5.13 gears and have much confidence that this is the right choice.

high-octane

Thanks for the responses guys. I think im going to go for it. Ill prolly regear anyway. I just wondered if it will be livable until i get the cash. Thanks again and any more input is welcome. Remember its an auto.

pearl-drum-man

Guess I missed that the first time, I thought all autos were 3.73 for 2008? I know for 2007 they were all 4.10. You might be a little better off than you think.

barbourjay

i have an auto and 33's. i have to turn overdrive off to make it uphill going interstate speeds. it's either that or it downshifts all the time.