Re-gearing: I think I get it now

Viking Jeeper

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So I have been on this forum for quite a while and have learned lots of great information about my TJ. 2005 with 3.73, six speed manual and metric 33's. I've kept my mouth shut but thought you guys were crazy with "you have to re-gear to go with 33's". I drove a 2006 rubi today with metric 33's and the auto and it was certainly a pig. So I guess I understand re-gearing for the auto but still think my 3.73 are fine with the manual. I've done lots of looking here and feel like going from 4.10 to 4.88 is not much of a change for the money but maybe the 5.13 is too much. Whats everyone running with an 42rle and 33's?
 
If you think 3.73 gears and a manual are fine for 33" tires you're right. I did it for 6 years with the 5 speed.

Regearing will make it a lot more fun to drive. I did that last year to 4.56 and regret not doing it sooner, though the 3.73s were fine.
 
I dont think I would ever re-gear 3.73 and a manual but am now convinced even 4.10 will not work with the auto.
 
For the 42RLE and 33's, no less than 4.88 but 5.13 would be ideal. The 42RLE's .69 Overdrive gear ratio requires a significantly lower gear ratio in the axles than would be needed for most other transmissions. And actually, due to the torque converter, automatic transmissions are more forgiving of being undergeared with larger tire sizes.

If you drove a TJ with a manual transmission with 4.56 gears with your 33" tires, you might no longer be as happy with your 3.73 gearing. :)
 
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The NSG370 makes up for the lack of differential gearing you have. If you had the 5 spd, I'd bet money you'd be far less happy with 3.73.
 
I drove mine with 3.73's, 33's and 5sp. for a couple years before re-gearing to 4.56's. I thought the 3.73's were bearable and just didn't use 5th gear much. Felt like I was taking off at stop signs in 2nd gear. Definitely wasn't good for my clutch. After the re-gear I kicked myself for not doing it sooner. Offroad performance was nothing short of amazing!
 
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4.10 with 35s was livable. 4.88 didn't make a night and day difference in any gear but 5th. The biggest change I noticed was offroad climbing large obstacles. Before I would need to use the clutch a lot to keep it from stalling. Now I can point at anything and it will either walk up it or break traction.

If I was to regear again (which I'm not) I would go 5.38 and sacrifice higher speeds on the freeway.