Anaerobic Sealant on Getrag Differential
04-12-2007, 12:21 PM
#1
Instructor
Thread Starter
Anaerobic Sealant on Getrag Differential
In case you suffer from the right axle cover leak (or left, for that matter) don't make the mistake I did and buy anaerobic sealant, new seals, and go to town. The solution is a more complicated than that.
I made the repair on both differential covers recently. I purchased many of the parts at the local NAPA store including the Permatex "Anaerobic Gasket Maker" especially recommended for differentials with "close fitting aluminum surfaces". After completing the repair, the drivers side plate sealed fine, the passenger's side still drips -- a drop or two, not after driving, but when it sits and cools overnight, as some have reported. (Expletive inserted here)
It turns out after talking with the Permatex engineer and studying the data sheet (http://devcon.com/techinfo/ANAEROBIC...T%20MAKER.pdf), I've learned that the Getrag aluminum surface doesn't have any ferrous or copper ions. The Permatex product likes to have those ions to cure properly. Permatex sells a separate "Surface Prep Activator" for about fifteen bucks a spray can that improves the cure speed and ultimate strength of the gasket. Without the activator, the gasket maker should work up to fifteen (15) thousandths of an inch; with the activator, the filled gap grows to fifty (50) thousandths of an inch.
I was a bit terse with the engineer in stating that if my still-leaking differential cover had a gap more than a few thousandths, of an inch I would gladly spend a day under his car -- as long as he took the other side of the bet. He didn't.
So I'm about to jump under the car and do the job again. My advice is to spend the extra 15 bucks for the activator and grumble to the sales clerk that it's robbery and that they should have thrown in the activator in the first place. Otherwise use the GM anaerobic sealant (PN: 1052942) and carefully read the directions to see if they require an activator or something special.
Another possible pitfall - especially if your local parts dealer doesn't turn over inventory very often - check the date code on the Permatex Gasket Maker. At the bottom of the blue tube, right where the tube is "pinched off" during manufacture there is tiny date code, something like 6JX1025H. The first number,"6", is the year of manufacture (2006). The first letter, "J", is the month (June). If the sealant is more than 2 years old, don't buy it -- it won't cure in your lifetime, even with activator.
I made the repair on both differential covers recently. I purchased many of the parts at the local NAPA store including the Permatex "Anaerobic Gasket Maker" especially recommended for differentials with "close fitting aluminum surfaces". After completing the repair, the drivers side plate sealed fine, the passenger's side still drips -- a drop or two, not after driving, but when it sits and cools overnight, as some have reported. (Expletive inserted here)
It turns out after talking with the Permatex engineer and studying the data sheet (http://devcon.com/techinfo/ANAEROBIC...T%20MAKER.pdf), I've learned that the Getrag aluminum surface doesn't have any ferrous or copper ions. The Permatex product likes to have those ions to cure properly. Permatex sells a separate "Surface Prep Activator" for about fifteen bucks a spray can that improves the cure speed and ultimate strength of the gasket. Without the activator, the gasket maker should work up to fifteen (15) thousandths of an inch; with the activator, the filled gap grows to fifty (50) thousandths of an inch.
I was a bit terse with the engineer in stating that if my still-leaking differential cover had a gap more than a few thousandths, of an inch I would gladly spend a day under his car -- as long as he took the other side of the bet. He didn't.
So I'm about to jump under the car and do the job again. My advice is to spend the extra 15 bucks for the activator and grumble to the sales clerk that it's robbery and that they should have thrown in the activator in the first place. Otherwise use the GM anaerobic sealant (PN: 1052942) and carefully read the directions to see if they require an activator or something special.
Another possible pitfall - especially if your local parts dealer doesn't turn over inventory very often - check the date code on the Permatex Gasket Maker. At the bottom of the blue tube, right where the tube is "pinched off" during manufacture there is tiny date code, something like 6JX1025H. The first number,"6", is the year of manufacture (2006). The first letter, "J", is the month (June). If the sealant is more than 2 years old, don't buy it -- it won't cure in your lifetime, even with activator.
04-12-2007, 02:09 PM
#4
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St. Jude Donor '08
Wow!!!
Great info and superb research!! Well Done! Sorry you had to learn the hard way.
Great info and superb research!! Well Done! Sorry you had to learn the hard way.
04-17-2007, 06:15 AM
#6
Team Owner
On the date code, the "J" is actually October. The months are in sequence by letter. I am using "6B" Permatex thread locker 242 on my FAST right now (February 2006). Also on the date, the temperature conditions for storage also play a role, if you buy it look for a store that turns over a lot of stock and a tube that is 6 months old or less. They also get pissed when you open the packet to check the date, as they are packaged with the date on the back where you can't see it. The guys in Advance Auto are still mad at me for opening every package and then leaving them all there and not buying any the other night 
04-17-2007, 06:46 PM
#10
Le Mans Master
From what I have heard, most case leaks are not around the drive shafts as most people first expect. They are because the side cover does not seal to the main body. Correct??
04-17-2007, 06:54 PM
#12
Team Owner
I used the GM anaerobic sealant (and new seal) and it didn't require activator. My driver's side diff cover has not leaked since. Been over 6 years now.
04-17-2007, 06:54 PM
#13
Team Owner
08-24-2012, 01:17 AM
#18
A necro-bump is better than an unnecessary new thread. This proves that SOME people out there know how to use that good ole' SEARCH function... or just like coursing through old threads haha! Plus this information is still great and relevant today as much as it was five years ago! 
08-24-2012, 07:34 AM
#19
Le Mans Master
