A tough winter? Pinion seal leak.

[Bonnewagon]

I was cleaning up the Bonnewagon after the snow had melted. I only used it a few times over the winter for Home Depot runs and that sort of thing. While under there I see that my rear end pinion seal is leaking. Damn, I changed to 3:23 gears about 5 or 6 years ago. I had changed out the seal at the time just because. I can't believe it failed already. Cheap seal? Cold winter? Just my bad luck?

 

[Clone TIE Pilot]

Did you use a tin cylinder when you reinstalled the yoke?

 

[1320John$$$]

I feel your pain I went out to the garage and I could smell something weird like a ton of mouse piss so I started looking around to see if any of the traps were tripped and I found one of my self-lubing Chevys in action transmission pan gasket sprung a leak

 

[CopperNick]

Add your rear driveshaft yoke to the list of possible culprits. As part of last years R 'n' R on the rear end of my Monte the rear seal got yarded out and replaced because it was junk. But, and at the same time, what I also found was that the seal surface on the yoke had developed wear and erosion right where the seal and the matching surface on the yoke came together. I thought about polishing the surface down but losing those few thousandths would make the seal "seal" looser and allow crap and corruption more opportunity to invade the site

So phoned over to Napa and lo and behold there is a sleeve available for the yoke to rehab the old surface. it is a Zero-zero fit and takes some patience to gently drift it down onto the shoulder because it is thin and flimsy. But you do get a new seal surface out of the deal. After that, I replaced the seal itself as well as the crush sleeve, put the yoke back on, and reset the preload using a torque wrench in inch pounds. Still have to replace the gear lube that bled all over the concrete; I hate incontinent rear ends! LOL

 

[Bonnewagon]

I have used the sleeves before on yokes and dampeners. Pioneer makes them. Even though they are made of stainless steel they don't last as long as Marine Tex. I clean the groove with acetone and then lay the Marine Tex on. Then I grind most of it down close. Then you must take over with a strip of sandpaper and run it back and forth by hand. Just as if you were polishing the toes of your shoes. If you do it right you can't feel the groove even with your fingernail. This way you don't reduce the diameter of the yoke. I have done this many times and never had a leak again. Of course all it takes is a grain of sand to get caught under the lip of the seal. It will cut the steel like a diamond. I think it must be the seal but I will know for sure when I take it apart. I heard a rumor it may go above freezing soon. Remember me doing this on the outboard motor propshaft?

 

[Rt Jam]

Check the vent.

 

[Bonnewagon]

Check the vent.

I did that first thing. Clear. It is a gravity leak. Just standing still it drips just enough to leave a patch on the ground. Worse, I have to keep refilling it from a jug of used gear lube that already has the posi additive in it. As hard as it is to do this job to begin with , being in the car makes it worse. I have to get it up high enough to squeeze my big butt under there. Luckily I have a Jeep companion flange holding tool that is a very close fit to the GM flange. A bit of grinding did the trick so now it fits both brands.

 

[64nailhead]

Ah, nothing like the smell of gear oil in the morning. Then get it on your shirt so you have that cologne on all day.

 

[Clone TIE Pilot]

If you don't use a tin cylinder when you slide the shaft into a seal you risk cutting it. Even a fine cut can slowly rip wider. Main culprits for slicing new seals are the sharp front corner ridge at the end of the shaft, splines, and keyways.

 

[Bonnewagon]

If you don't use a tin cylinder when you slide the shaft into a seal you risk cutting it

I've never heard of that. Are they available or home made? Most books advise oiling or greasing the seal/shaft so that doesn't happen. If the shaft is splined I usually wrap it with masking tape to protect the seal. A companion flange is pretty smooth at the end.