Pinion bearing replacement

[cjsxj87]

Hokay so my pinion bearing is fisted. How hard would it be to replace? Any tips? Im going t try and not bring it to someone who does gears.

 

[ktm racer 419]

in a 44?

just remember where the shims go and have at it.

always replace the pinion nut as well.

just remember torque specs on the carrier bolts. i usually just crank down the pinion nut with an impact because im too weak to get it torqued to spec.

blocks of wood and a good hammer are usually needed to get it out of there.

 

[cjsxj87]

Nah, my 30.

 

[kastein]

Theoretically the new bearing should be fine. If you feel like it, buy two sets of pinion bearings (same lot from the same manufacturer preferably) and a shim kit and make one set into setup bearings, reset the pinion depth (start with same shim pack from before, clean it real well with brakleen or measure and use new shims of the same total thickness) and preload and it SHOULD line up fine. Run a pattern before and after.

That's if you want to do it perfect though.

As for setting the pinion nut torque, I have the opposite problem... I tend to break bolts off. Fortunately haven't broken anything that important yet.

 

[cjsxj87]

What are you supposed to set the pinion nut torque too? Ive read about marking the pinion and nut so that I will put it on the way as before. Or should I just crank down on the pinion nut?

 

[rweaver138]

Or should I just crank down on the pinion nut?

This is what I did, I think it's somewhere around 185 ft lbs.

 

[XJLI]

i've always had to put a breaker bar and on the ground with the axle still in and move the jeep forwards or backwards to loosen the pinion nut.

just removing the nut to change the bearings you shouldnt have a problem... like sam said remember the shims... just remember how tight it was when you loosened and it tighten it that much. torque spec is something ridic high.

 

[jeeperjohn]

You should torque the pinion nut around 200 foot pounds or so. If you don't have a torque wrench for that high a torque then tighten it until you feel the pinion nut bottom out on the yoke then go another 1/4 turn.

 

[rweaver138]

Yeah my torque wrench only goes to 150 ft/lbs so I torque it down with that then give her a little extra with a cheater bar, hasn't failed me yet :thumbup:

 

[kastein]

Mine goes to 200 or 250, forget which, if you guys ever need to borrow it let me know.

I can generally get a pinion nut off by tossing the axle on the ground, putting my big pipe wrench on the yoke, and cranking on it with my breaker bar. It's not THAT bad... a 14b or d60/70/80 pinion nut, on the other hand, would be pretty tough.

 

[rweaver138]

big pipe wrench on the yoke, and cranking on it with my breaker bar

this

 

[foxwar71]

I <3 torquing pinion nuts.



Which pinion bearing is it? you can change the outer one without disassembling the entire axle. In my case, my outta wack front d-shaft only wore out my outer bearing, simple 20 minute fix under the jeep, new outer bearing/seal/pinion nut later, all fixed.

 

[jeeperjohn]

I <3 torquing pinion nuts.



Which pinion bearing is it? you can change the outer one without disassembling the entire axle. In my case, my outta wack front d-shaft only wore out my outer bearing, simple 20 minute fix under the jeep, new outer bearing/seal/pinion nut later, all fixed.

Chances are if one of the pinion bearings has excessive wear, the other one does too.

 

[foxwar71]

Chances are if one of the pinion bearings has excessive wear, the other one does too.

Very true. I caught mine early, the pinion nut mighta even started to loosen up and maybe only that was the problem. A new outer bearing and new/torqued pinion nut resulted in a fix for me. I more or less got lucky I didnt have to do the inner.

 

[cjsxj87]

Thanks guys! Yeah Im going to replace both. The pinion bearins are pretty fisted.

 

[jeeperjohn]

Thanks guys! Yeah Im going to replace both. The pinion bearins are pretty fisted.

Might as well do the carrier bearings at the same time since the carrier has to come out anyway. Make sure you put a strong magnet on the inside of the diff cover to gather wear metal out of the oil.

 

[kastein]

Might as well do the carrier bearings at the same time since the carrier has to come out anyway. Make sure you put a strong magnet on the inside of the diff cover to gather wear metal out of the oil.

... since you're an axle expert, what's your take on having to reset the gears when the bearings are replaced? I've always wondered about this, figured what I'd do if I needed to replace bearings is run a pattern, replace pinion bearings and re-shim if needed to get the same pattern back, then replace carrier bearings and re-shim as needed to get the same pattern back again. Probably overkill but my thinking on it was that getting the same pattern back after doing the pinion bearing leaves me with a known correct carrier offset / backlash setting and also a known pinion depth, so I don't have to worry about adjusting the shims on both the pinion and carrier at the same time since the two settings affect each other to some degree.

 

[jeeperjohn]

... since you're an axle expert, what's your take on having to reset the gears when the bearings are replaced? I've always wondered about this, figured what I'd do if I needed to replace bearings is run a pattern, replace pinion bearings and re-shim if needed to get the same pattern back, then replace carrier bearings and re-shim as needed to get the same pattern back again. Probably overkill but my thinking on it was that getting the same pattern back after doing the pinion bearing leaves me with a known correct carrier offset / backlash setting and also a known pinion depth, so I don't have to worry about adjusting the shims on both the pinion and carrier at the same time since the two settings affect each other to some degree.

If the pattern is good before you remove the carrier then any changes will be the same on both sides and even if it wasn't the same on both sides any change would be negligible. The difference between a new and worn bearing is unlikely to be even .001". It is better to let it go back in in the same configuration to prevent any excess wear caused by the mesh changing. If the pattern is way off then it might be necessary to make changes but at that point you might as well install new gears.

 

[kastein]

Awesome, great to know :cheers:

Time to order a new set of pinion bearings for the 30 I'm building with 4.10s!