The rear pinion seal was replaced about a year ago .I just started driving I noticed some seepage at the seal . I used a national seal I also put grease along the spring and some sealant on the outer edge before installing. The bolt was marked before removal . Should I tighten the bolt another 1/8 more ?
Rear differential pinion seal seeping - tighten more?
- Thread starter 1blkc5
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I wouldn't do that, you could alter the preload/backlash and it will probably not cure the seepage. If it is not a leak that drips on the ground just keep an eye on it.
I have a leaking pinion seal although I have replaced it twice over 10 years. The previous owner or shop gouged the diff housing fairly significantly upon prying the seal out. It was leaking some when I bought the car, replaced it and did the same as you, adding RTV around the new seal. Drove it in flush and it still leaked where the seal meets the housing.
Changed it again during an axle ratio change and used more-better sealant. Nope, still leaks from the gouge I assume. I sanded the gouge down a little but I really need a sleeve to be pressed into that area and no one makes those.
Changed it again during an axle ratio change and used more-better sealant. Nope, still leaks from the gouge I assume. I sanded the gouge down a little but I really need a sleeve to be pressed into that area and no one makes those.
That will not solve anything. The seal is faulty. Marking the nut also is not the correct way to set the preload. There is a detailed procedure in setting the pinion preload using a pointer type inch pound torque wrench and you did it incorrectly. If you cannot do it correctly, you are best to just keep the gear oil up the the proper level.
Kestas
Staff member
It doesn't take much to have a leaky seal. I used to look at differential seals that came back from warranty. The most often reason for leaky seals was nicking during installation. Often these nicks were spline-spaced. Some use a tool to shield the splines during seal installation. Only rarely was there a defect in manufacturing the seal. You need to have a deft hand to install a seal, you can't "gorilla" it on. Same goes for the shaft surface. It must be perfect. Additionally, the circumferential grind lines of the shaft can't have an angle (called a "lead angle") that would allow lubricant to be pumped out during operation. Of course you know that the seal must be installed with lubricant.
I don't see how tightening the pinion nut would solve the leakage problem.
I don't see how tightening the pinion nut would solve the leakage problem.
Check and make sure the vent isn't blocked causing pressure to build up in the diff when it gets hot and force oil past the seal.
Unless it is a Teflon seal then no lube, all surfaces must bone dry. If you lube it it will leak. If it has a spring it is not Teflon.
Lifetime doesn't mean much on a ten dollar seal. It's the labor involved. I would look more closely at the polished surface the seal lips ride on for imperfections or your new seal will leak too. I would use new gear oil you plan to refill the differential to lube the seal lips on your conventional style seal.
You should read up on how to properly set the preload and do it right. If overdone you will be changing out the crush sleeve and having to do it again.
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I have seen rtv and yellow glue used around outside of the seal and all work fine. You have to protect the seal from the splines just like you do seals in an automatic. I have used plastic cut from pop bottle to wrap around the splines. I always warm the seal up either in the same hot oil bath as my ring gear or with a blow dryer. I then grease lips of the seal and put my yellow glue or my rtc on the outside before I install it and drive it home carefully.
I always make sure the pinion's mating surface is smooth as well. I do this with axle seals and crank seals same same!
I always make sure the pinion's mating surface is smooth as well. I do this with axle seals and crank seals same same!