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Discussion Starter #1
I know this has been discussed before...but cant seem to locate it.....Here's my question:

I'm running 33 mtr's currently....and w/my LJ and my 6sp,and stock running gear, i have no problem leaving in second gear, unless on a severe incline....if i opt out for 35's ....(clearance etc NOT coming into play)......will i achieve a lower rpm ? as now i average 2800-3000 rpm's on the freeway ?
 

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Yeah as you increase the tire size the rpms will drop. However the Jeep can run 3k rpms on the highway no problem. I have 35s with the stock 4.10 gears and its out of the powerband now. Acceleration is sluggish and theres not near the power on teh highway, but I'm turning lower rpms. Can't wait to get the gears swapped out. I've actually read that you get better gas mileage with the correct gears as the engine is in the powerband eventhough its turning faster. It has to do with how far you have to press the gas pedal down to maintain speed.
 

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Discussion Starter #3
I take it u use 1st for take-off......is it really sluggish....i mean...i'm a pretty conservative driver......don't wind-it-out unless i need to quickly pass a moron because he can't drive......i mean i'm usually crusin in 6th even @45-50....on slower highways or country roads...works great....
 

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Your RPM's will drop as the tire size goes up. My experience with going from 33" to 35" tires left me unhappy with the Jeep's sluggishness until I changed the gear ratio to 4.88. I was much happier after the gear change and my gas milage improved when I got back in the "power band" as RockRunner85 said.

At a set speed, your RPM's will drop by about 6% when you go from 33" tires to 35's. With 35's the RPM's will be about 13% lower than when you had the stock 31" tires.

You will need to get a device to reset the speedo if you want accurate readings. I like the Truspeed that I added.


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'04 Solar Yellow Rubi: Nth long arm, Tummy Tucker, HAD, JKS body lift and MML, skids, ORO U-Turn, 35" BFG muds, 4.88's, Superior axles, Warn 9.5xp, etc.
 
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