Trying to understand axles / gears

YellaTJ

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Sebago Lake, Maine, USA
I've recently purchased an 01 TJ 4.0 5speed. It's set-up on 33s and I feel the axles are not geared for 33s.

Front axle is a Dana 30 3.07 gears

Rear axle is Dana 35 and I can't make out the axle tag for gear ID. Assuming 3.07 to match.


Also, is it normal to have two different sized axles? Dana 30 and 35?
Thanks in advance
 
Yes it’s normal. Yes. The gears will match. So you have 3.07 (you’ll learn to hate that ratio). You’ll need to regear for 33s though.
The Dana 35 is horrible axle. It makes a better boat anchor really.
 
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Dana 30 and Dana 35 combo is normal. Both axles will have the same 3.07 gears. That ratio is from the factory and the worst Jeep offered. Not trying to be mean, just honest. With 33’s and that transmission you’ll need to regear to get it performing well.
 
Dana 35 is not horrible. If your never going over 33’s you’ll be fine
 
3.07 would definitely be the worst possible gearing you could have for 33s. So yeah, you definitely will want new gears!

Having a Dana 30 front and Dana 35 rear is 100% normal. The rear axle always has to be stronger than the front, because a Wrangler is a rear wheel drive vehicle. Even when in 4WD, the rear axle is still taking more load than the front.
 
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Thank you all for the info!

As the jeep sits now it has 33x12.5 15s on it, I'm planning on running 32x11.5x15s due to better tire selections.

I'm leading towards the 4.10 gears, what are people's thoughts/inputs?

And as I read, should I be replacing the Dana 35 for a Dana 44 or is it fine just to upgrade the gears in my current Dana 35?
 
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C-clips and same size shafts as the Dana 30. Its not what you would call a good axle.
The beloved 8.8 is also a c-clip axle. That isn't the part that breaks, only the design feature that allows for the wheel and remaining shaft to fall out when the shaft snaps.

Short of replacing with a Dana 44, the Super 35 kit is a very good option for improving the Dana 35.
 
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Thank you all for the info!

As the jeep sits now it has 33x12.5 15s on it, I'm planning on running 32x11.5x15s due to better tire selections.

I'm leading towards the 4.10 gears, what are people's thoughts/inputs?

And as I read, should I be replacing the Dana 35 for a Dana 44 or is it fine just to upgrade the gears in my current Dana 35?
32/4.10/5 speed is a decent combo. Maybe 4.56? Consider the Super 35 kit if you want a rear locker. The Dana 44 is the better option, but you need to weigh the costs of finding one.

Grimmjeeper.com is a good resource for understanding gear and tire size combinations. You want your 70-75mph to be pushing 3000rpm.
 
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