dellpjJK

I spend too much time on the highway. I changed my order to 4.56s. I cruise comfortably in 5th gear at about 75mph and 2600 rpms, so if I can do the same in 6th gear with 35 (according to the chart, I think that will be best. I gain a gear and get in the right power band.

sneck

I'll add to this discussion, I recently regeared to 4.88s. I have a 2011 (so the 3.8), and a 6 speed. However, I'm still using stock rubi tires. First gear is pretty much non-existent, save for when I'm in traffic, but on the highway its great to be able to put it into 6th and still accelerate going up a hill! my rig is probably a bit heavier than most (jku, steel front and rear bumper with ace rails and extra skids), but I look forward to putting some bigger tires on my rig in the future. I think if 4.88s are barable with stock tires, that they would be fine with larger tires. would love to hear from some folks with 4.56, see if they think they lack the bite they were hoping to get or if its just what they wanted. seems weird to spend the coin to regear to something not so deep

teskymo

I have the factory installed 4.10 gear's which came with, 2011 Rubicon. I since have went to 35" 12.50 17 tires and a 3.5" lift. I get around 17 mph too, my problem is that as I go down the road and it shifts into overdrive the Jeep all of the sudden fills like I just pick up two more tone's of weight and it begins to want to slow down. I mean you can fell the difference big time. I've wondered if I should have change my gears? or should I just stay with what I got? I'm confused too.

drgreybow

On my 6 speed, I have 35's (MTR w/ kevlar) that measure out to about 33.75 on my rig. I have been running 4.88's for over a year and often wish I would have gone with 4.56. I think a lot of it depends on where you live, what kind of driving you do, and what the speed limit is. Most of my driving is on the highway where the speed limit is 75 here in Colorado. It really feels like the engine is working hard to keep that speed. If you live where the fastest you can go is 65 or 70, then 4.88 with "35's" is probably ideal. The upside is I now feel like I can look into a 37 that runs a little small for my next tire.

If you're on the fence on which gears to get, I'd suggest finding somebody in your local jeep club or town that has regeared. See if they'll let you test drive their rig so you can see what it would be like. They'll probably be flattered that you want to check out their rig and you might find a wheelin' buddy in the process!

Bonedoc

I have to agree. I have a 6sp manual and run 37s. I went with 4.88s in my JKU and many people told me to go with 5.13s. I even ordered the 5.13s and returned them when I decided to stick with my gut feeling and go with the 4.88s. Turns out that, for my situation, the 4.88s are absolutely perfect and 5.13 would of been way to low. If my Jk was NOT a daily driver and use most as a trail rig I would of gone 5.13.

Bonedoc

Just as a side note. I agree with this as someone who owns a MANUAL JK. I have no experience with an auto and everything I've read point to going as low as possible with an auto to get your performance back. So for anyone reading this thread who has an auto realize there is a huge difference between the effects of gearing on an auto vs a manual.

JE8154

I need to learn how to read...

Ronstar83

Driving a 6 speed manual in an 08 JKU and wondering how a supercharger will effect my regear. Will it be best paired with a 4.56 get get the best mileage as a daily driver but performance on inclines? Has anyone regeared AND thrown a supercharger on in a manual transmission? It's hard for me to wrap my head around how the supercharger will effect what gears to use. Maybe I supercharge it and then like my 373's? I have now idea.. I was told not to do both at the same time, but I'm not sure where to start. It sounds like 4.56 and RIPP may be the best combo and 4.88 and RIPP would be a high revving gas sucker. I'm just looking to get more power between 40 to 75 mph. It is slow off the start but the worst for me is downshifting to 4th and sometimes 3rd on the highway to climb the grades here in Oregon!! I don't want to gear so that I loose a ton of top end either..

mgdwj

i have a 2007 2 door x with 35's and a 6speed. when i regeared i went with 4.88's. befor with my 35's and the stock 3.21's i was getting about 17 on the highway now i am getting 11-12 on the highway. in town i really dont use 1st, 3rd, or 5th. when i do a lot of highway driving i widh i would have went 4.56's but i have plans on going up to 37's and that should make it a little better on the fuel milage. on the trails the 4.88's are great even with the 2.72 tcase.

dellpjJK

This confirms that I'm choosing the right gears by going with 4.56s.