Rear Differential Front Oil Seal Leak

[Tools R Us]

If, at the beginning of my pinion seal leak, I would have took this advice, I would have missed all the other problems I've found. Geez, Tools....our 80's are 20+ years old! If you're driving one why not get the right attitude...like realizing you're going to be spending time on it to keep it rollin' on down the highway or up the trail. How many fingers you got to plug all the holes in the dike?

I still have a couple of fingers that aren't in holes!

We are "a little" busy right now, putting a new short block in a S/C rig, so little time for fun work.

 

[Tools R Us]

It's not the destination, it's the journey. Besides everyone needs a hobby. As far as way to spend time and money this beats the hell out of sitting on a bar stool or drinking beer while watching SportsCenter. For me anyway.

I prefer wheeling to to polishing serviceable parts, but whatever floats your boat!

 

[Tools R Us]

I have some 1/8th inch cable wire that wouldn't go through this fitting. After working it around a bit I got it through and now have a better opening for sure. So it was definitely clogged. I also tried blowing through the breather line and that was a no go.

I doubt I am out of the woods and will be ordering a new breather here shortly. I'm guessing this blockage has caused the oil to seek the path of least resistance which is the oil seal.

Get some 1/4" line, like 8' and a small, like old school VW fuel filter. Run the line from that fitting into the jack compartment, cap it with the filter near the fuel filler. A free flowing breather is better than the stock setup, something like this.

 

[nukegoat]

Solid collar? Unless the plan is to be a bigtime rock crawler it's not needed. History has proven the crush sleeve works fine for most of us. Most of the rigs I wheel with have them, never an issue.

I actually don't even think solid collars are "stronger" than crush sleeves. I just don't see how they would be - they only react against the nut itself so even the claims of "hitting a rock" or whatever don't make sense - all that load goes into the bearings themselves

 

[shack]

It's not the destination, it's the journey. Besides everyone needs a hobby. As far as way to spend time and money this beats the hell out of sitting on a bar stool or drinking beer while watching SportsCenter. For me anyway.

Yeah this is definitely my hobby. Wrenching on my truck is the complete opposite of what I do for a living on a day to day basis. Last summer I did my vsv and all new hoses. Granted it took me a month....I had fun doing it and just did an hour here and there when I had time or was frustrated with something at work(I work from home).

I already have a feeling I am going to be taking things apart down around this rear. It's just how it goes.

 

[Tools R Us]

I actually don't even think solid collars are "stronger" than crush sleeves. I just don't see how they would be - they only react against the nut itself so even the claims of "hitting a rock" or whatever don't make sense - all that load goes into the bearings themselves

Agree, kinda, maybe, I like solid collars, fiddly, all race car and stuff, can make future servicing easier, slightly, maybe. But experience says that crush sleeves work, lots of bent driveshafts, dorked yokes, flanges, type of carnage and never a failure that could be attributed to them. If I were to take my diff apart, would likely go with a crush sleeve, they are easy to setup and work.

 

[danthman114]

while youre getting the seal, pick up a sand blaster... that's a lot of rust...

 

[Prairie Swamp]

Needle scaler then sand blast.

Looking back at the pics - that's a lot of clean oil really fast there. Doesn't have the caked dirt look of a slow leak. I bet it was the plugged vent that is fully responsible for the leak. Could fix the vent and clean it up and drive and see what happens.

 

[shack]

while youre getting the seal, pick up a sand blaster... that's a lot of rust...

The rust is going to be the death of me.

 

[nukegoat]

Agree, kinda, maybe, I like solid collars, fiddly, all race car and stuff, can make future servicing easier, slightly, maybe. But experience says that crush sleeves work, lots of bent driveshafts, dorked yokes, flanges, type of carnage and never a failure that could be attributed to them. If I were to take my diff apart, would likely go with a crush sleeve, they are easy to setup and work.

Yeah. I like the fiddly nature and ability to disassemble and reassemble. But that's me. And I'm weird.

 

[danthman114]

The rust is going to be the death of me.

brownells website (or was it Sinclair) has a paint called alumahyde that's an epoxy based. when it dries and is cured per their instructions, you cant scratch it...

 

[80t0ylc]

Get some 1/4" line, like 8' and a small, like old school VW fuel filter. Run the line from that fitting into the jack compartment, cap it with the filter near the fuel filler. A free flowing breather is better than the stock setup, something like this.

I thought about doing this years ago, but what concerned me was gear oil smell inside your rig. Do you get that sometimes? It seems to me when the diff gets hot, you'd smell the venting. Maybe not, though. With this in mind, I terminated my vent hose outside, in the wheel well near the fuel fill assy shown in your pic. Tied it to the vent hose. It's behind the rear shield in that wheel well so somewhat protected.

 

[Tools R Us]

I thought about doing this years ago, but what concerned me was gear oil smell inside your rig. Do you get that sometimes? It seems to me when the diff gets hot, you'd smell the venting. ...

Never, even in desert hot conditions, lot of them setup that way. The compartment is the exhaust for cabin air, so the flow is out through the vent by the window.

 

[BILT4ME]

Never, even in desert hot conditions, lot of them setup that way. The compartment is the exhaust for cabin air, so the flow is out through the vent by the window.

I had thought about this too, but that's my definitive answer. That's how I'll do mine then.

 

[Cruiserdrew]

For no scientific reason I like the solid collars, and for $50 extra, it's worth it to me. I do agree that crush sleeves are OK but solid collars are definitive. I think as I have geared and re-geared over 20 years, all of my Land Cruiser diffs save one are solid collars. Make a difference? Don't know, but I do know I have done what I can do to have the strongest possible set-up.

Remember the original Toyota diffs up to about 78 ALL had a solid collar built into the pinion, and the pinion preload was set with shims. I bet they switched to crush sleeves to speed up production line work, not because it was superior.

Anyway-carry on, with careful set up both methods will yield a durable set up.

 

[JeepinPete]

I'm with Tools on this one. My rear pinion seal went out last spring, and the front pinion seal started leaked the end of last summer. Both were replaced as Tools described, neither has leaked since. 20+ year old trucks, the seals all around are wearing out...

 

[shack]

After freeing up the clog in my diff breather at the axle and taking it for a drive yesterday I didn't have any leaks until about an hour ago when the drips resumed. Now I have a puddle about the size of a Ritz cracker.

Loose pinion bearing preload can cause a leak, so if you havent already done so, engage the parking brake, put the tcase in neutral to remove any load on the driveline, then wiggle the joint to see if your pinion bearings are loose. If they are, unstake the nut and retorque and restake, then clean off all the oil and drive it a bit to see if it still leaks.

This has been the case twice for me, and I figured it was worth mentioning in case you didn't already check.

The only motion I am able to get from this test is about a 1/4 inch of rotation from the drive shaft. Nothing else budges.

 

[Tools R Us]

...
Remember the original Toyota diffs up to about 78 ALL had a solid collar built into the pinion, and the pinion preload was set with shims. I bet they switched to crush sleeves to speed up production line work, not because it was superior.
...

Maybe or could have been to increase reliability? We have seen our fair share of shims spit, pieces go into the pinon bearing and take it out. Have made solid collars, then whittled them to size, so no shims are needed, lots of fiddling. There is no free lunch!

 

[shack]

I am approaching the end of being able to push off this problem. I took a 100 mile round trip drive last week and speeds averaged probably 60-65MPH. When I got home and parked in my garage I noticed fluid splatter on my rear bumper, rear tailgate and rear windshield. Mind you before I left I had no apparent leaks on my garage floor.

Upon further inspection here is what I found. You can see that pretty much everything underneath is soaked. Covered in gear oil. I thought for a second it could be brake fluid but checked my levels and things look good. Also, the smell... gear oil has a distinct pungent smell.

How hard of a job is replacing the rear diff front oil seal?

Other than this spot what are other places prone to leaking if its not at the wheels? Could it be from the rear diff lock actuator? I haven't been able to replicate any further leaking since returning from this past trip.

 

[shack]

Here is a pic of one of my shocks. Everything covered.