I have 35" tires and 4:10 gears. I live in Chicago so the elevation is 900ft. When I go out west through the rock mountains will I be in truck line going 25 mph??

or If I drive in 7,000 to 9,000 ft like in Wyoming how would my jeep act??


Thanx

 

I have 33 GYs and stock 4:10s, recently moved to VT and its terrible. 6th is completely useless and 5th on some long hills is even boarderline. I predict you will not e happy.

 

I have 32" BFG MTs on my 4.10 six speed. Some of the passes in Colordo can knock me down to 45-50 MPH and 4th gear if I don't make a preemptive downshift before losing speed. I could do better, but I try not to exceed 3000 RPM unless it would impact traffic.

 

You don't say whether you have an auto or 6 speed, 2 or 4 door. I have a Rubi 2 door, 6 speed, 4.10s and 35s. Cruise control is useless on the slightest of hills and the more elevation, the worse it gets. Preemptive double downshifts (to 4th) are required. I am not familiar with the 4 door or auto but IMHO you are going to have to exceed 3000 rpm either way. I wind the crap outa mine.
C'mon Jeep, put a real engine the Wrangler!

2008 Rubicon
Superchip
K&N drop in air filter
3.5 AEV lift
35X12.50R17 Kevlars

 

I have a 4 door auto. So besides going up hill. If I 8,000 ft just going straight my rpm will high ?? What sux about it??

 

Last year some friends and I went to Colorado. My pickup ('05 Dodge Cummins) with 4 big guys in it was pulling my 22ft Haulmark with a Jeep (TJ Rubi), three motorcycles and all our gear it it. The TJ with 4.10's and 33's following us with two guys in it couldn't keep up in the hills. Think 3rd gear floored and still slowing down.

 

I have 4.10's and 33's, auto trans. It sucks. Not enough power. Seriously cannot use overdrive. Then add in a 40-50 mph head wind and forget it. I had to get a Superchips Flashpaq and put the 91 tune in. That helps. I'm still not doing cartwheels over it, but it is better.

 

If your driving on the freeway (not wheelin') then no over drive on the "hills". I have 32 4:10 and going to woodland park and a bit higher I do OK. Sometimes I may down shift to keep up with traffic, even with the auto. I have not taken the JK on highways or "large hills" >10k that I was not wheelin'. I have not seen any real issues, but I don't have 35".

Altitude will not affect the JK, I have gone to 13k+ (wheelin') and there was no real issues with altitude changes to the JK.

For you, that maybe a different story, have water with you. The hikers rules (which can apply to driving) is you lose 1 liter of water for every 1k ascent. Some folks get altitude sickness driving passed 8k. But if you drink water (lots) a few days before going over the hill (before coming to CO), then you should be OK with it. feel a bit dizzy, stop, drink water and get something small to eat (trail mix).

Just to let you know, the strange feeling you get when >9k and you get out of your JK to take it in and walk a bit, is normal.

Are you going to do some wheelin' or passing through?

 

lol i have a 4 door auto on 37s w/410s - i have effectively turned the transmission into a 3speed auto - and after i hit about 1500 feet if there are any hills and i dont speed up to 80 on the down slope im downshifting to 2nd and winding the motor - gears are on the top of the list for me - it was bad before at stock with constant downshifts to 3rd and occasionally 2nd

- im hoping in 2011 or 2012 they offer the rubi with a real motor and transmission so i can trade this pile in and actually be able to drive it to the trails

lol - gears will solve most all your issues though cant wait to get some 5.38s in mine then i should be golden

 

Stock gears, auto trans, and mountain grades = 2nd gear at 5000+ RPM for miles and miles and miles. The higher the altitude the worse it is.