What gears and why?

LakeBeard

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I have a 2004 Rubicon, running 35"tires. What gears should I have and why? It mainly off road, very little on road, mainly desert
 
I have a 05 Rubicon 6 Speed manual running 35's and 4:88's which works great for me especially having the Rubicon TC with lower gears than the std. TJ . Now if I only used it off road I might go one deeper
 
I have a 2004 Rubicon, running 35"tires. What gears should I have and why? It mainly off road, very little on road, mainly desert
The what depends on the transmission, the why is so the jeep's power makes it to the rear wheels .
 
Yep , and get to know the overdrive switch .
 
5.38s from revolution. 35s on 42RLE
Same here, don't consider any other ratio for that combination. My used TJ with 35's and 42RLE came with 4.88 and it was a dog on the highway, never even getting 12 mpg. I regeared it to 5.38 from Revolution Gear and the engine was much happier on the highway afterward, my mpg even jumped to well over 14 mpg. Of course that 5.38 ratio is superb off road. Especially while crawling over the rocks.
 
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Same here, don't consider any other ratio for that combination. My used TJ with 35's and 42RLE came with 4.88 and it was a dog on the highway, never even getting 12 mpg. I regeared it to 5.38 from Revolution Gear and the engine was much happier on the highway afterward, my mpg even jumped to well over 14 mpg. Of course that ratio is superb off road too.
Good post , the 42 RLE is geared tall, and their is no substitute for a proper final drive ratio - moreso with this transmission possibly than any other.

Inherited improper gearing creates a false baseline of performance - you will think it is just how it is, and often the new owner has no idea how off the power and acceleration is, along with the tractable control you want off road , which is a strong point of the 4.0.

What sometimes happens is guys or their young sons slap on big tires, it is awful, they aren't willing to invest in regearing or comprehend the need , and eventually sell it because they don't enjoy it . Then the next owner gets it, and never knew any different, so regearing doesn't hit home with him either.

Once it gets regeared, you totally understand.
 
I have a 05 Rubicon 6 Speed manual running 35's and 4:88's which works great for me especially having the Rubicon TC with lower gears than the std. TJ . Now if I only used it off road I might go one deeper
If I had a trail rig I would totally go straight to 5.89... 3500 RPM at 70 all the way

I'm eventually going to 4.88 on the 6 speed. The nice thing is 4.10 and 5th gear (1:1) is exactly the same drive ratio as 6th gear (0.84:1) and 4.88. So I know exactly what the OD performance is going to be.

I agree with everyone else. 5.38 for the 42RLE. 5.89 might risk too much vibration, 5.13 won't be enough.
 
Are the 5.38 recommended mainly for highway driving? This is not my daily driver, mainly stays in the desert, low speeds on pole roads and stuff.
 
Are the 5.38 recommended mainly for highway driving? This is not my daily driver, mainly stays in the desert, low speeds on pole roads and stuff.
5.38 is the lowest Rubi axles can go
 
And I agree with the Revolution Gear choice. They set up easy and run very quiet. They are also circle K gears which are desirable.