Rear pinion seal and bearing?

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NWMO
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Rear pinion seal and bearing?

Post by NWMO »

Good evening friends,

I’m needing to replace a leaky pinion seal on my rear diff. I got the seal and this two piece bearing set (only bearing style I see on RA for the rear pinion shaft). I do not have a new “crush” spacer and doubt this is the correct bearing set. The FSM leans towards replacing the ”front” bearing at the same time. Is that necessary? or can I only address the seal and see how things go? I’m pretty certain my rear end noise is the passenger axle bearing (will confirm when I pull it) while working on the pinion seal. TIA!

Chris
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rer233
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Re: Rear pinion seal and bearing?

Post by rer233 »

I've replaced a few rear pinion seals (never a bearing.) I get the driveshaft out of the way, mark EVERYTHING by the flange (flange, nut, and pinion shaft) count the number of turns it takes to remove the nut, pop out the old seal and install the new one. Then put the flange back in the same position relative to the pinion gear, install the nut the same amount of turns that I took it off, and line up the marks. Maybe I'm being overly cautious, but that way I retain the original pre-load. Always worked for me.
As for the axle bearing, just remove the 4 bearing retainer nuts, put the brake drum on backwards, start the wheel nuts loosely, and use the drum as makeshift slide hammer. You'll probably have to take the axle to a machine shop to get the bearing pressed off and the new ones pressed back on. Not a bad idea to replace the axle seal too.
if it aint there, there's a good chance it won't break!
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NWMO
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Re: Rear pinion seal and bearing?

Post by NWMO »

I got a different axle swapped in this evening, just need to address the pinion seal now. Thanks.

Chris
Psalm 37:4 "Delight yourself in the Lord and he will give you the desires of your heart"

In remembrance of my friend ARCHINSTL:

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"

"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
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Petros
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Re: Rear pinion seal and bearing?

Post by Petros »

it seems you should be able to take it apart and just replace the seal, and put it back together the same way it was. but I have known people that have done this on the Tercel4wd rear axle and it ended up not just leaking, but damaging the diff bearings, and eventually trashed the ring and pinion.

the crushable washer is used only for first first factory assembly, and the FSM has you using steel shims as a shop procedure to get the lash just right on assembly. I have also been told by diff technicians that those crush-able washers eventually allow to much lash in the gears over time and should be rebuilt with the steel shims. years ago I worked at a place where they routinely installed different ring and pinion gears, and LSD diffs, with new shims and seals. Getting the gear lash correct appeared straight forward, you have to trial and error the final bolt up to get the right amount of gear lash (or clearance): too much, or not enough, will cause damage and you get very short gear life. I have never done one myself, but I talked with our diff tech about it, and I remember saying it does not look that difficult, why do so many mechanics mess this up? our shop was hired by Nissan to make an instruction video to educate their dealer machanics on how to property assemble the diff to get the correct ring and pinion clearance. he expressed the same wonder at why so few get it correct. it does not appear difficult, but it must be done in the correct sequence, and the final clearance must be correct, or they gears will destroy each other. Perhaps most flat rate mechanics do not want to take the time to do it properly, it can be time consuming without power tools and the right jigs.
to
The point is, the diff parts stack up and final torquing is sensitive to get tje correct assembly and clearance between the ring and pinon gars. Many home mechanics can do this correctly, but it usually is not considered a DIY project. You may get it all back together properly by just replacing the seal, or you may not, and end up having to replace the whole diff assembly later.

Something to consider before you pull apart your diff.
Good luck.
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NWMO
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Re: Rear pinion seal and bearing?

Post by NWMO »

Thanks Peter,

I will let you know how assembly goes soon.

Chris
Psalm 37:4 "Delight yourself in the Lord and he will give you the desires of your heart"

In remembrance of my friend ARCHINSTL:

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"

"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
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NWMO
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Re: Rear pinion seal and bearing?

Post by NWMO »

Well, I got the new seal in and the pinion back in this evening. I will test drive this weekend some time. The pinion nut got within 1/4 turn of original location pretty easily. It took a little over 100 ft-lbs to get it back to the original alinement. It’s not jumping out at me right now, but max torque allowed is around 150 ft-lbs, so I’m optimistic.

Chris
Psalm 37:4 "Delight yourself in the Lord and he will give you the desires of your heart"

In remembrance of my friend ARCHINSTL:

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"

"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
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