Rear Pinion Seal Leak (1 Viewer)

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Sep 3, 2016
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Tennessee
Hello everyone, as you can see fro the title my rear pinion seal is leaking. Oil is running out where the drive shaft connects to the diff and its no small amount, but not to where I cant keep the level up.

I have been searching the forums for ways to fix it and there are two drastically different ways to go about it. For my wrench experience, not many months under my belt, bought 5 months ago. But have done all the baselineing my self along with rebuilding the front and rear axles, brakes, rotors, calipers, throttle body clean out, new valve cover gasket, installed OME lift, replaced headers and all new exhaust system.

Anyways first do yall think i would be able to tackle this and second which method to use. I have seen Users mark everything so they can line it all back up once the seal has been replaced, some replacing the crush sleeve others not. And i believe the (FSM) has a different method of replacing it altogether, which seems to take alot more time, but you will end up with the proper ratio.

If i were to go with leaving the diff on and marking the nut, would the ratio be fine? Also if i go this route I know i would need a 30mm socket breaker bar and other miscellaneous tools, but are the any other items that i would need? A new Crush Sleeve? New lock Nut? And if i need these items, what would be the best site to get them?

Thanks for the help in advance guys.

!!CruiserOn!!!
 
easy-peasy method is mark nut - replace seal - and go 1mm past your mark when tightening.

but if your rig is lifted and you havent corrected upper and lower control arms......then your slight driveline vibration is effectively pounding on the seal. i would correct your diff angle first- then do the seal. and while you are at it check your u-joints which if are bad is also inducing some pounding/ vibes which are acting on the seal.

if you are running any lift over 2-2.5" then the changes to diff angle need correction even if vibes arent felt- they are there and being ameliorated by loose joints seals and vibeing thru axle to tires which can absorb whats left .
 
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Also check that your rear DS slip isn't hydro locked, this stresses the whole system.
 
easy-peasy method is mark nut - replace seal - and go 1mm past your mark when tightening.

but if your rig is lifted and you havent corrected upper and lower control arms......then your slight driveline vibration is effectively pounding on the seal. i would correct your diff angle first- then do the seal. and while you are at it check your u-joints which if are bad is also inducing some pounding/ vibes which are acting on the seal.

if you are running any lift over 2-2.5" then the changes to diff angle need correction even if vibes arent felt- they are there and being ameliorated by loose joints seals and vibeing thru axle to tires which can absorb whats left .


I put the 3'' OME lift on and corrected the caster in the front control arms, but havent done anything to the rear. Do i need adjustable rear control arms or what?
 
easy-peasy method is mark nut - replace seal - and go 1mm past your mark when tightening.

but if your rig is lifted and you havent corrected upper and lower control arms......then your slight driveline vibration is effectively pounding on the seal. i would correct your diff angle first- then do the seal. and while you are at it check your u-joints which if are bad is also inducing some pounding/ vibes which are acting on the seal.

if you are running any lift over 2-2.5" then the changes to diff angle need correction even if vibes arent felt- they are there and being ameliorated by loose joints seals and vibeing thru axle to tires which can absorb whats left .


What should i be looking for in the Ujoints?
 
yes- 3" lift could use a 1/4" longer lower control arm (LCA)and adjustable uppers.(uca) You can skip the lca if you arent concerned with centering a 37" wheel in the rear.....but the adj.UCA is the way to get the diff back to stock.

alternatively if u can weld/fab.....a better option than adjustable UCa is to raise your axle side mount....this puts your uca back to level/parallel/stock and keeps the diff angle correct thru the suspension cycle/ travel. most people go the adjustable upper route as thats easier and seal life and ujoint life loss is negligible compared to stock.

longer LCa will correct for wheelbase loss, slight effect on caster, and recentering of wheel in wheelwell (if rubbing in front on 35 or 37s / flares etc.

the lift has also shifted your rear axle to one side if the panhard hasnt been lengthened.....but again 2 ways to correct this......easy is adjustable......better is raising the axle side mount which gets the panhard more parallel thus allowing more oem cycling of suspension without the side to side axle movement. adjustable is the way most people go and they live with a ever so slight highway speeds side to side movement over stock. for many this is imperceptible as larger tires will soak up that side to side movement with the tires sidewall flex.....thus dissipating the rear end shimmy for the most part.

for u-joint- grease em up and then grab driveahaft and joint and tug hard/ feel for any play. if you have driven with the uncorrected lift for years.....those vibes have been slowly beating on the pieces of the puzzle to where pinion seal and ujoints take some wear./wear out faster than stock/no vibes.

this all also applies to the front axle....panhard adj. / caster adjust and pinion angles/vibes/ujoints.etc.
 
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No, the right side upper control arm.

All right, I'll bite... I do have oil slung on the right side upper control arm. Is this indicative of the severity of the leak? I have been watching the leak for over a year now and there doesn't seem to be any appreciable change of fluid level in the diff.
 
yes- 3" lift could use a 1/4" longer lower control arm (LCA)and adjustable uppers.(uca) You can skip the lca if you arent concerned with centering a 37" wheel in the rear.....but the adj.UCA is the way to get the diff back to stock.

alternatively if u can weld/fab.....a better option than adjustable UCa is to raise your axle side mount....this puts your uca back to level/parallel/stock and keeps the diff angle correct thru the suspension cycle/ travel. most people go the adjustable upper route as thats easier and seal life and ujoint life loss is negligible compared to stock.

longer LCa will correct for wheelbase loss, slight effect on caster, and recentering of wheel in wheelwell (if rubbing in front on 35 or 37s / flares etc.

the lift has also shifted your rear axle to one side if the panhard hasnt been lengthened.....but again 2 ways to correct this......easy is adjustable......better is raising the axle side mount which gets the panhard more parallel thus allowing more oem cycling of suspension without the side to side axle movement. adjustable is the way most people go and they live with a ever so slight highway speeds side to side movement over stock. for many this is imperceptible as larger tires will soak up that side to side movement with the tires sidewall flex.....thus dissipating the rear end shimmy for the most part.

for u-joint- grease em up and then grab driveshaft and joint and tug hard/ feel for any play. if you have driven with the uncorrected lift for years.....those vibes have been slowly beating on the pieces of the puzzle to where pinion seal and ujoints take some wear./wear out faster than stock/no vibes.

this all also applies to the front axle....panhard adj. / caster adjust and pinion angles/vibes/ujoints.etc.


I do not daily drive it, only when I'm driving to the trail. I'm running 35' on it and haven't noticed any rubbing in the back on the front of the fender, but to be honest i haven't paid it much attention. I've only been out to the trail twice since I've gotten it with the lift on.

I think i would have to go with adj. UCA because my fab skills are lacking with lack of equipment. With the adj. UCA how do i tell how much to adjust them? And are they hard to install?

Also, how much play should the u joints have, if any?
 
typically adjusting back to stock angle via digital angle tool. harbor freight i think has a cheapie magnetic one. ( i forgot what stock angle is- but someone will likely post up) or someone may have the eye-to-eye length for you with the 3" of lift.

ujoints should be rock solid with no play- if you grease em via zerk til the grease squirts out and theres still play when tugging on em......u joints need replacing or you need to lay off the steroids.
 
I do not daily drive it, only when I'm driving to the trail. I'm running 35' on it and haven't noticed any rubbing in the back on the front of the fender, but to be honest i haven't paid it much attention. I've only been out to the trail twice since I've gotten it with the lift on.

I think i would have to go with adj. UCA because my fab skills are lacking with lack of equipment. With the adj. UCA how do i tell how much to adjust them? And are they hard to install?

Also, how much play should the u joints have, if any?

I went with a longer LCA and subsequently now sell them. I did this for a few reasons.

First i wanted to retain the stock drive shaft configuration, that way you don't need adjustabilty.

Second I wanted a heavy duty LCA that could be used for a slider and add some protection for the gussettS.

Seemed to me to provide the best bang for the buck and all you do is bolt them on
 
All right, I'll bite... I do have oil slung on the right side upper control arm. Is this indicative of the severity of the leak? I have been watching the leak for over a year now and there doesn't seem to be any appreciable change of fluid level in the diff.

I've seen that a few times now and each time the outtter pinion bearing was shot and the diff needed to be rebuilt.
 
I've seen that a few times now and each time the outtter pinion bearing was shot and the diff needed to be rebuilt.

Hmmmmm...... Thanks. That gives me something to ponder :(. I get no noise, vibration, or play in the pinion so I think I'll continue to monitor oil level for the time being.
 
Hmmmmm...... Thanks. That gives me something to ponder :(. I get no noise, vibration, or play in the pinion so I think I'll continue to monitor oil level for the time being.
On the ones I saw, when I removed the pinion nut and flange the pinion slid into the diff. The race on the bearing had worn to a point the it wss loose.

Also in 2002 (?), Toyota redesigned that area and it is now larger on both the front and rear.
 

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