I have the 6speed, 4.10 and 35"s and have no issues. I use 6th all the time (except some hills) It really is a good combo. I stated in another thread I had the opertunity to drive a 6speed, 4.88 and 35"s and there was a difference, but not enough to move gears to the top of my list. I have the PJ CAI, Gibson Exhaust (now pretty bent as of sunday!!) and use the Hypertech on the premium tune and it really is quite a decent drive compared to stock, not much power loss. For my money I am going to wait till funds are easily available and I finish a few things first and then just go to 5.13s.

 

y'all except for Edwin have no idea how much better it is once you regear, you should really see if you can drive someones jeep if you know anyone who has, but then again you'll want to regear the next day haha

 

You have an automatic don't you?

Just for reference with 35s and 4.10s my overall ratio is almost identical to your ratio with 35s and 5.13s.

Your auto with 5.13s turns 2546 RPM at 75 MPH.
My 6 speed with 4.10s turns 2479 RPM at 75 MPH.

Gears would be nice but with the 6 speed and 4.10s 35s are no problem (very similar to your current setup).

I'll eventually go with 4.56s or 4.88s. It'll be nice having a little more gear for crawling and a little more oomph without downshifting. But I'm not looking forward to going back to having super short 1st and 2nd gears and spinning 3,000+ RPM at 75 MPH.

 

Apparently you didnt read all the threads. I have driven someone elses Jeep with a similar setup to mine and different gears. Was there a difference, yes there was, was it enough to make me do it tomorrow.......nope.

 

Most of us got the 5.13's before the 5.38's became available. If I were doing it today I'd probably go with 5.38's. I'd much prefer to move up another 125 rpm at 75mph.

The only possible problem, that would make me think twice about the 5.38's, is the 2nd downshift. If you're cruising along at 75 and downshift to 3rd (1:1) it's to about 3400-3500 rpm. Now in the hills of Colorado and at altitude if you need more it downshifts to 2nd gear. And that translates into (with 35's and 5.13's) into 65 mph at 5500 rpm which is redline. Now the thing is, in 2nd gear the cruise will hold me at 65 on any grade I've encountered. Usually I'm in the left lane passing almost everybody and the trucks are doing 15-20 in the slow lane. That is pushing it pretty hard though. A 5.38 would be doing 62 mph during that situation so it's probably not a big deal. The first time the above happened to me I was sure surprised to see the JK do 65 mph in 2nd!

FWIW the calcs show in the 2nd gear 5500 rpm scenario that 4.88's would do 68 mph but I have no idea whether or not it would hold that speed. The auto JK would have been a better vehicle with a 5 speed auto instead of a 4 speed. One of the advantages of the Hemi conversion is the move to a 5 speed auto.

 

i know how sluggish i'm going to be with 35's and 3.73 gears. i know this and do have plans to re-gear with in the next year. i plan on 4.88's with ARB lockers. but want it all done at one time. so i'm going to have to live with the poor performance of the 35's with stock gearing. it's all part of the master plan that will happen in time.

 

Yeah, there is no sense in paying double labor if it can be avoided.

 

i have 35's with 3:21's my jeep is a slug going with. i am hopefully ordering my 5:13's from dave this week. can't wait i will be able to move again

 

5.13's is a lot for a 6 speed. You will be about 60% higher RPM's on the freeway. Your going to be at about 3100-3200 RPM's at 75mph

 

i meant 4:88's i don't know why i wrote 5:13's oops i was not paying attention sometimes im in space. i might go 37's in the future if i was not i would just get 4:10's but i don't want to have to do it twice.