Can anyone recommend something to cure a very slight(but enough to be annoying)leak from a differential seal.You know,one of these miracle treatments that actually works,without killing the 9" after a coupla hundred miles ?I really don't wanna have it apart if I can avoid it,cos like I said its only slight.

 

I need this too.. rebuilt the darn thing, new seals, still leaks..

Oil ends up behind the nut.. didn't put any grease on the splines. NOW they tell me!! (didn't see that in ANY book anywhere)..
I also forgot to put the dust collar on.. I'm gonna take mine to the local rear axle place.. rumor has it they can pull the nut, seal and re-install without pulling the gear..

Sam

 

You really shouldn't take the nut off without replacing the crush sleeve, but it's done all the time to replace the seal. It's a quick cheap and easy fix.

 

Neat panel. I have used a product made by one of the big name companies [that I can not recall] that is a sray on red stuff that will indeed stop such a leak. I will look tonite a post the brand if still needed. It is a well known brand of auto supplies. It needs heat to work so you have to either drive between coats [takes two or three] or I have used a heat gun to accomplish same effect. It does work though. Darn I wish i could remember the brand. Blue can with red lettering. Oh well, I will look tonight. Joe

 

Thanks man,
That would be much appreciated

 

aw hades man if my old frods werent leaking on the drive then something would be wrong ................. replaced my pinion seal once now in the factory dana and it's doing it again . im just assuming they're marking their territory .

 

Kripfink if it is the pinion seal leaking then the spray on stuff is most likely not the answer. I thought you were referring to the center section to housing gasket. Sure like your panel, one of the more attractive I've seen. I do agree with 55f350, sometimes I feel like if one of my three has no leaks it is probably out of fluid in something.

 

For me, anything that would goop up the leak, would probably goop up the new posi.. so that ain't happenin..

Sam

 

Permatex "Form a Seal" Leak Sealer. Mine also says NAPA on the label, so obviously that is where I got it. Also have a can that does not have that on the label. Sam, if it is a gasket leaking slightly it will not get in housing. It is somewhat messy and red in color, but I have masked off around the leak before. I have used it on high milage company vehicles that come back from quick lube joints with stripped drain plugs. I believe it can be used on 9" housing gasket pretty successfully.

 

[quote=sdetweil;6270672] I'm gonna take mine to the local rear axle place.. rumor has it they can pull the nut, seal and re-install without pulling the gear..

Sam[/quote
and would that be DriveLine of Austin? They did mine. $

 

Joe,
It is the housing gasket,so I've got some on order & give it a try.Thanks for your help.

 

Yep, Austin Drivetrain on Anderson by the 183 intersection. yes, they are not cheap.. we tried to put a posi on my son's 66 chevy pickup a few years back, and just couldn't get it to the proper lash.. turns out there are two different gear depths, depending on ratio, and we had a mismatch.. cost $700 for them to fix it, adding in the spacer.
but I have another crush collar and did the rebuild myself, so I 'could' do it again..

Funny thing about mine is that it leaks behind the drive shaft flange..(this is a ford/mustang/lincoln/8.8 setup)
I unbolt the drive shaft flange and pop it toward the front and there is probably 5 tablespoons fulls of gear oil there.. so it must be leaking down the splines..

no leakage at the seal outside before the yolk.

Sam

 

I'd first check to see if the differential breather clogged, this has caused leaks more than once.

taking off the pinion nut and installing a new seal is something i've done quite afew times. some diff's have crush sleeves and others use a stack of shims. if you have the shims type it's very unlikely you will change the pinion bearings preload when removing and installing the nut. if you have the crush sleeve style (ALBUQ F-1 is correct, it should be replaced) but it's much more costly and most folks are willing to give the seal a try. i'd ask someone who's set-up alot of ring and pinions before to do it. there is a good chance you could crush the sleeve more which would preload the bearing too much (burn them up) not tight enough (too loose) is also very bad and will burn them up.

a couple tips; I only use "National" brand pinion seals, many setup kits use a cheap single surface seal. national is a quality dual lip seal.
also, i almost always buy a new pinion nut. if unable to locate or something, i crush a section of the nut to ensure it has a good "locking feature". you don't want this nut backing off.

you'll need to polish the surface on the pinion yoke the seal rides on. if it's pitted from rust or has bad grooves where the new seal rides it won't do any good to intall a new seal, and and you'll need a new yoke also.

i've seen gear oil leak up the spline and behind the nut also. some kits come with a fancy "star" shaped rubber seal, if you can't find one for your application, clean everything very good and put a 1/4" bead of "permatex "ULTRA" under the pinion nut washer before installing.

last thing........... i never us Amsoil or anything that is thin.
80/90 wt. gear oil.............. i've seen the others leak too much.

last thing, your gears should not sound any different after your done. if you rearend starts getting noisy after this, it will NEVER get better on it's own. the less you drive it the less damage you'll do before getting it rebuild at a shop.....

 

I have done tons of pinion seals with great success without changing sleeves. All you have to do is mark everything with a centre punch. Start by marking the pinon nut, then the end of the pinion shaft and then the yoke. All you marks should be in a straight line with each other.Now hold the yoke from turning while removing the pinion nut.(may need a buddy) Count the number of turns it takes to remove nut. Tap off the yoke and replace the seal. Inspect the yoke for curves worn into the seal surface by the old seal.Add some oil to seal surface and slid yoke back on lining up your mark on the yoke and pinion shaft. Next install the nut counting the turns going back on. Tighten nut till your marks lines up and nut has turned back on the exact number of turns. The key to not collapsing the spacer is counting the turns so it goes back together exactly in the same spot.

 

great. thanks, that is the key, lining things up.. I can do this with the bed wood off, from the top instead of the bottom..

whats the trick to stop the leak thru the splines? Someone said wheel bearing grease on the splines before sliding the yoke back on..

Sam