Differential cover sealant question

Reece

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So I am in the middle of changing diff oil. I used RTV to seal the cover, I noticed permatex wants me to wait 24 hours to fill and return to service.

My question. How long you you folks wait to fill your diffs, the full 24 or something less?
 
I waited the full 24, only because I'm buy the book and would rather be safe than sorry!
 
Let it set up for about 15 mins then fill. We did thousands of diffs that way when I was in the biz, no leaks.
I agree. If 24 hrs., in business you'd be keeping customer's cars overnight and pushing them around so you could bring other ones into the shop!
 
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So I am in the middle of changing diff oil. I used RTV to seal the cover, I noticed permatex wants me to wait 24 hours to fill and return to service.

My question. How long you you folks wait to fill your diffs, the full 24 or something less?


I honestly don't know the answer to your question. However, that's because I use Lube Locker gaskets in both the front and rear, I never have to wait for RTV to cure. Something to check out at a later date.
 
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I honestly don't know the answer to your question. However, that's because I use Lube Locker gaskets in both the front and rear, I never have to wait for RTV to cure. Something to check out at a later date.
Do you put your gaskets in dry or use gasket sealer? I used to use sealer (different type of vehicle) and it was a pain in the butt every time I removed the diff. Too much scraping and cleaning. I pulled the rear cover off of a Cherokee diff on the weekend and I think the last guy used way too much RTV - it was every where including small clumps mixed in with the fluid. I'm going to try a gasket this time.
 
Howdy, I agree with 'Serbonze'. I quit using silicon sealant and started using Lube Locker gaskets on my diffs. I'll never go back. You don't need sealant, the Lube Locker gasket has silicon sealing lines molded on it and I've never had so much as a damp spot. Plus, you never again have to suffer through cleaning old sealant off your diff and cover mating surfaces and I've re-used the gaskets several times with no issues whatsoever. Good luck with your project!!
 
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I've done this quite a few times with the same results. Reinstall cover, put tools away, then fill er up. Never had a leak.
 
So I am in the middle of changing diff oil. I used RTV to seal the cover, I noticed permatex wants me to wait 24 hours to fill and return to service.

My question. How long you you folks wait to fill your diffs, the full 24 or something less?
I only use Mopar RTV diff sealant specific for gear oil. It is the best diff cover sealant out there and I fill immediately. It is also able to be used on oily surfaces. I don't have the luxury of waiting even a few hours when I replace a cover most of the time. If I had a sealant that wanted me to wait that long I would in all likelihood give it to someone I didn't like very much or throw it away.
 
Howdy, I agree with 'Serbonze'. I quit using silicon sealant and started using Lube Locker gaskets on my diffs. I'll never go back. You don't need sealant, the Lube Locker gasket has silicon sealing lines molded on it and I've never had so much as a damp spot. Plus, you never again have to suffer through cleaning old sealant off your diff and cover mating surfaces and I've re-used the gaskets several times with no issues whatsoever. Good luck with your project!!
There are a few issues with gaskets. If you play in the rocks, they don't work. You bump the cover on a rock, it compresses the gasket, cover springs back into place, gasket doesn't and now you have a leak.
If cleaning the sealing surfaces is too much for you to handle, you may consider getting someone to help you with working on your rig. It is at most a 5 minute exercise to clean both with a wire brush on an angle grinder, scotch brite disc on a die grinder, hand scraper that is purpose built, or even one you make yourself. You have to clean out the diff and inside of the cover anyway, so what difference does it really make if you have to spend a few minutes cleaning some sealant off? I'd much rather clean both diffs and covers than do one block for a thermostat swap and they only use a gasket.
 
Me I do wait one to three hours, depending how long the side task took. Jonathan my stepson no wait anytime.
Any of the Jeeps Diff leaks so far.

I do said that if you have that kind of time on hand follow manufacturer suggested product use.

That is a suggested cure time. Keep on mind that from all the RTV Sealant you put in just a few amount remain between the cover and the actual differential face.
 
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I scraped off rtv from hundreds and hundreds of diffs during my time in the shop. And you guys are traumatized by doing one or two;):D
I scraped off hundreds and ... well dozens and dozens of British car diffs and they are a pain. RTV isn't commonly used - pretty much all gaskets and sealer only. There is no cover plate. The whole aluminum case and gears have to come out. That's not hard but they're heavy and you basically have to hold it down on the bench with one hand and scrape with the other. I haven't done that many Jeep covers - all RTV and pretty simple. I haven't seen one with a gasket but I think I'll try that on the cover I have off now.
 
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I let mine dry overnight and filled her up ... no leaks. My last Jeep had a Lubelocker in the rear and that thing always dripped. It must of had something tweaked, but RTV is a simple task and much cheaper.
 
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