Well I have a 2007 4 door Sahara Manual. The manual migh be my problem, but I wanted to see some thoughts on my power issues when I wheel. Of course I knew that I would have some power issues on the highway, but that isnt why I got it. It has 37 inch tires and a 6 inch lift. I tried to go up a hill that I did just fine with my TJ but didnt have enough power to get up there with the 4 door. Am I using the clutch incorrectly or do I need to get a run at it. I am little afraid to run at it, cuz, SPEED kills. Any thoughts

E

 

I can see where 37s and not re-gearing might cause power issues...

EDIT: That's the short answer - obviously there are a ton of variables. Your jeep in a low gear and with transfer case in 4-LO should be able to turn 37s... it just won't do it as easily as a jeep that is geared "correctly" so to speak. Most people with 37s probably running at least 5.13 gears, if not 5.38.

 

3:21 and 37in = not good :(

change your ratio ASAP

 

Thanks for the info guys. Wasnt thinking. Still new to the experience. Checking on new gear ratio now. Thanks again.

 

4LO, when wheelin put it in 4LO

 

I powered up a few hills in a 4cyl TJ - granted it only had 33's but in low range it did just fine.

Maybe you need to change the gearing to make hills a little more comfortable. Or, AEV sells a nice Hemi retrofit kit

 

I ran 37s with the stock Rubi gears (4.10) for a bit, and yes there are some power issues to say the least. Regearing is necessary. 5.13 is the way to go IMO with a manual. However, with the 4.10s in 4lo it did okay on most climbs assuming the RPMs stayed up, but I wouldn't want to just leave it that way.

 

After looking at that chart, I could go with 40's and be back at basically stock gear ratio with the 5:13's i have now. SWEET.

 

jkkat, a "40" might not even really measure 40, so you will prob be prefectly fine. only thing is the weight is also a consideration.

And this chart cannot be that accurate... My "35" s really measure 34, and using this chart, it says im good to go with 3.73's. NO WAY, my OD is useless

 

I think the white represents factory Rubi gearing. The stock X and Sahara configurations are in blue (base is 3.21 with 29's, mine came with 3.73 and 32's). A Rubi would be 4.11 with 32's.

Also, that color coding seems more relevant to 4 doors. My 2 dr X is fine in the blue.