rubimonster

I run 35's plan on going to 37's. Tow a camping trailer in summer which is near the max tow capacity of the jeep. Should I re-gear to 5.38's at a quoted price of $1600. Or should I take that $1600 and buy a quality chip or programmer, with a CAI and save some $. Maybe with the leftover $ I could put some towards a LOD rear bumper....finally. My guess is the most improvement in power gain is going to come from re-gearing. Any advice would be appreciated!

JayhawkJeep

Gears hands down. Programmers are good but nothing beats gears.

myz28u

Regear is best mod. All others are band aids to fix regear

nthinuf

For an auto on 37's with stock gears? And then make it even heavier with a rear bumper/carrier?

You realize that Ripp suggests regearing before buying their S/C, right? And it is a hell of a lot better than a chip and cai...

Have you found the Drivetrain FAQ's yet? Start plugging some numbers in and see what you come up with, but as the others said, gears will be your single biggest performance gain. After you get your drive ratio in line, then start looking at wasting money on an intake...

Pluke the 2

invest in a tranny cooler. cost like $50.00 and it lowers temps about 40-60F

Jeter

gears fo sho. tranny cooler fo sho if your towing. 5:38 is the gear you want fo sho.

w squared

Regear to the 5.38's and get a tranny cooler.

You will still need a programmer to get your shift points and speed set up properly though - but you can handle that with an AEV Procal which is not expensive.

Camo

I'm new and have read your post, please explain what 5:38 gears will do to change his tow issue, what about those gears when not towing? is that both rears need to be changed, what does that do to gas miles? thanks I have a Sahara on order with a tow pkg and that changed the gears to 3:73 from 3:21 I noticed the Rubicons come with 4:10s very confusing.

w squared

There are a lot of factors at play in the OP's question. He's currently on 35 inch tires, going up to 37 inch tires. He's also running an automatic transmission, and pulling a heavy trailer.

Running shorter gears (5.38's) will provide more mechanical advantage for the engine when he's pulling that heavy load - especially since the larger tires make it more difficult for him to pull it.

In the same way that your having 3.73's is better for towing than the standard 3.21's makes it easier for you to tow, his having 5.38's will make things easier for towing.

By the way, I see you typing in the gear ratios as 5:38 or 3:71. They are actually expressed as follows:

5.38:1 - meaning that the driveshaft will rotate 5.38 times for every revolution of the tires.

or

3:71:1 - meaning that the driveshaft will rotate 3.71 times for every revolution of the tires.

Since every ratio has the same ":1" on the end of it, we normally don't take the time to type it out - we just show the first number, usually to two decimal places. When we're talking about gearing, we just say the number without the decimal place. 5:13 would be "five thirteen". 4.10 would be "four ten". 3.71 would be "three seventy one"

Clear like mud?

Camo

clear like mud, exactly! but asking is learning so I'm asking. Thanks for the response I guess his gas mileage is in the toilet. The 35's alone must hurt could not imagine 37s plus the gear change.