Gear swap

Heya everyone i have a quick qeation about swappiung gears out..I ordered 4.11's for my rig and got them but the fronts are the wrong ones i was wondering if i could go ahead and install the rear gears and just not run in 4x4 until i get my new ones for the front.Hence i would leave the 3.55's in the front axle and run the 4.11's in the rear until i get the correct 4.11's for the front..Would i have to remove the front driveshaft to do this or am i safe to leave it in and just run the Jeep in 2wd????Thanks in advance..

You can run the rear gears and leave the front alone if you want. Like you said, as long as you dont put it in 4wd you should be fine.
However, yank the dshaft just to be carefull. If you accidentally put it in 4wd, or someone else does, a lot of things can blow up.

What do you mean by "correct" 4.11s? Did you get low-pinion instead of hi-pinion, or did you get 4.10 and think you should have 4.11?

Yes, you can run 3.55 in front and 4.10 in the rear in 2wd, but I'd recommend dropping the front driveshaft just to make sure you don't accidentally pull it into 4wd at some point.

If you have a 231 you can, if not pull the front drive shaft. Probably should anyway just in case someone else drives your rig.

I have the 242 t-case...Should be the same though thanks for the fast input guys!!!

242 REQUIRES that you pull the drive shaft, its FT 4x4.

Nevada City Sparky said:

242 REQUIRES that you pull the drive shaft, its FT 4x4.

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2wd is the same wheather it be 231 or 242. 2wd is 2wd.
FT and PT are options of the TC. It does not operate in FT unless the TC selector is in FT.

Luggz,
In 2wd you will be just fine with different gears front/rear. No problem.
Just to be on the safe side of things, I would go ahead and remove the front DS. It's cheap insurance.

Nevada City Sparky said:

242 REQUIRES that you pull the drive shaft, its FT 4x4.

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Not all the time it isn't. The New Process 242 has these modes:

2WD high: All power going straight through the case to the rear wheels.

4WD high and low part-time: a locked connection front to rear just like a NP231 in 4wd.

4WD high full-time: The full-time mode allows some front to rear torque bias through an open center differential. It is NOT a viscous coupling like a ZJ/WJ... it's more like an open differential in an axle.

With a NP242, one CAN remove either driveshaft (not both ) and operate the vehicle. The front output is a (sealed) Double Cardan yoke. Remove the front shaft and run in 2WD high or 4WD Low. If the rear shaft must be removed, seal up the output and run in 4WD Part Time high or low.

I just recently put about a thousand road miles on a 242 in 4WD high, front wheel drive, open front diff. It is a bit awkward in tight turns... the front UJs are doing a LOT of work...just like when wheeling on high traction surfaces though.

Just trying to clear that up! :wave:

I still want to know how the gears are the 'wrong' ones...

Is it that the stock carrier won't work with gears about 3.55?

Nevada City Sparky said:

242 REQUIRES that you pull the drive shaft, its FT 4x4.

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SPOBI

actually, technically, you could drive the 242 in full time with two different ratios, cuz of the open center diff.... but it would probably damage the diff or overheat the fluids and bake something.

people who have wheeled in full time know this, as you can have one front tire picked up off the ground and it gets all the torque.

again, i would pull the driveshaft, but you dont have to as long as you stay in 2WD.

-Tim

Yucca-Man said:

I still want to know how the gears are the 'wrong' ones...

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+1.

As for driving on the rears alone, I've been doing exactly that for a couple of weeks. I regeared the front to 4.10 and have been driving on the original gears in the back (2WD NP231) for a couple of weeks. I'm in the middle of putting the 4.11s in the back this weekend.

There where not reverse cut ones...
I have a buddy that has a set of gears that i thought would work but then i read along and i see that the older style axles use shims on the pinion and the newer style 99 and up axles use a crush spacer on the pinion..Does anyone one know this to be true and would an older style pinion still work with a crush spacer???Or can i just use shims in place of the crush spacer???