I much prefer permatex #2 over most RTV sealants. I can't tell much difference with how well they seal, but the #2 is much easier to clean up. Especially with a gasket that gets replaced frequently like a rocker cover on an older car.
Hot tip with it take a pea sized ball on the tip of your finger and thinly smear it around the mating surface on either side of the gasket. It should glide on smoothly and you should be able to see the metal surface though the brown permatex #2. This is really nice when dealing with auto transmission pan gaskets since you don't need to worry about it gunking up the filter screen if you use too much by accident.
I have dealt with so much bullshit from gaskets are supposed to be installed dry with shit put on them that doesn't belong and a lack of sealant in places where it does belong. If you can't seal this with a dry gasket you are missing some other, serious problems.
Honestly doesn't matter. Just make sure the rim of the cover is nice and flat up against the diff. Add a little bit of blue thread sealer on each bolt. Send it.
We used plain ole grease to coat fibre gaskets for oil pipeline joints and blanks, on tankers. That way they didnt stick to the flange and were reusable, and it made assembly easier if you didnt have someone helping you.
Its worth it. Lubelocker or no gasket at all. Gasket + sealant is a no go. If no gasket just get anaerobic flange sealant like loctite 518. Ive done a couple differentials.
They operate a company out of the same building called Jim's Gaskets. They have been in business for decades and Jim's are the only gaskets reputable Harley engine builders use. They are absolutely the only gasket I would use in a hard to get to spot. The silicone bead makes a huge difference; especially when the surfaces are perfectly glass smooth and flat.
I thought RTV on these types of a gaskets wasn’t recommended? I’ve always heard it’s either one or the other. This would be my first time using a gasket on a rear diff cover.
In a perfect world you shouldnt need rtv, in reality covers aren’t perfectly flat and it will help. I wouldn’t use the gasket personally unless you need it for ring gear clearance, but it won’t hurt anything to use both. The main thing is to use a gear oil safe rtv and follow the instructions.
A very thin amount on each side is all that's needed.
I agree with the other poster; if it was new/perfect then probably ok. But a ultra thin amount on each side will help.
Just use the 90minute right stuff or Ultra and let it dry at least 4 hours. I like the 90minute right stuff as its usually good to in 30minutes if warm and an hour if cool.
Throw it away and use "right stuff" silicone. Gaskets are stupid and are a leak point. Silicone will never let it leak. The dealership doesnt even use a gasket anymore.
Have you ever used the "right stuff" by permatex. It will never leak. Im a 25 year mechanic and its the greatest stuff invented. I will never use a different silicone again.
I have, it's good. I like the three bond stuff better though. I was just remembering when people would try to seal synthetic oil with the red rtv...didn't work worth a damn
Doesn’t matter which side faces where. Clean both surfaces well, make sure it’s centered, and torque evenly. A light sealant can help, but flat and clean matters more than direction.
Lots of different info in here. What I would add is, it is very important that you DO NOT BLOCK those little rectangle cutouts if you do use silicone. Those holes have to be clear and if you look at the axle housing you'll see round holes that they line up with.
This is so oil can flow into the axle tubes and down to the wheels bearings to keep them lubricated. If you look at the cover you will see some indentations where as the oil gets slung around it funnels it through those holes.
I have see many bearing failures where either the gasket didn't have those holes or they gobbed way to much silicone on there effectively blocking the passages. You can do some google searches and find this is a very common mistake
Ok, now as someone who is a career mechanic. Most the time I would skip the gasket and just use silicone (my favorite is the permatex Ultra Grey for everything). If I did use the gasket I would coat the whole thing with a THIN (not thicker than a dime) layer of silicone. Just enough so I can't see the paper. Then I would install to a good cleaned and prepared surface, get all the bolts threaded in. Then tighten till they and all just starting to squish a little out, then final tightening with a ratchet.
Personally I don't like how small the oil holes are so I would be tempted to ditch the gasket or modify with scissors to better fit the flat surface of the cover. And the other thing that's important is that your cover is relatively flat and not bent (usually from prying the old one off) which can be sorted out on a good flat surface with a hammer.
Test fit it on both parts. Seems like the bolt holes lineup but the little slots are in different spots. So you know it fits on that part, but what does it look like on the other part it gets bolted to
From what I understand the gears should not be submerged in lube and the magnet will only be useful at the bottom of the diff. So fill hole and magnet at the bottom.
Which ever way fits in the trash can better and then use rtv to seal the diff up. Ill use a gasket on anything except a differential. Every few years ill give one a shot and then a few months later remember why I don't use them when it starts leaking. Just my opinion use it if you feel like it.
The only reason I’m using a paper gasket here is because that’s what was on the old cover and it never leaked. Diff had something like 100k miles on it with the paper gasket before I opened it up. Only other trucks I’ve had I used RTV on the diff cover and they never leaked.
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The answer is it doesn't matter as long as the bolt holes line up.
They definitely line up. Thanks for the advice.
When in doubt, part numbers out
Wait…part numbers out of putting it on the cover or sticking it on the pumpkin? Crap I confused myself.
yes
I like that
[deleted]
OP asks about the gasket orientation, not the cover. The cover can’t be installed upside down as it wouldn’t clear the ring gear.
Oops my bad
It does not matter. If the holes line up your good.
I would suggest though adding some Permatex #2 on that gasket just to help make a good seal.
Isn't permatex #2 the really nasty stuff that never hardens...? Ultra black is my go to
Yes it is. It's far easier to remove though. It dissolves with acetone so if you ever need to pull that assembly apart it'll be easy cleaning it up.
I much prefer permatex #2 over most RTV sealants. I can't tell much difference with how well they seal, but the #2 is much easier to clean up. Especially with a gasket that gets replaced frequently like a rocker cover on an older car.
Edit. I suppose I need to give the #2 a go with these comments!
Hot tip with it take a pea sized ball on the tip of your finger and thinly smear it around the mating surface on either side of the gasket. It should glide on smoothly and you should be able to see the metal surface though the brown permatex #2. This is really nice when dealing with auto transmission pan gaskets since you don't need to worry about it gunking up the filter screen if you use too much by accident.
I'm a big fan of the brown#3 aviation gasket sealer.
Another vote for Permatex #2, not as "permanent" for removing and reinstalling your part someday
There is actually a green that is for gear lube
Ultrablack has been my goto for everything. Waterpumps, oil pans, corner dabs on valve covers.
Zero comebacks from it leaking later. Sucks for the next guy but that's his problem. My goal is zero leaking.
Much like my wives expectations I choose the good ol fashion 1 minute gasket maker. I’ve never had a comeback with that stuff.
Permatex #3 aviation is the way
This is the way
Please enlighten me. Didn't know there was a number 3.
I have dealt with so much bullshit from gaskets are supposed to be installed dry with shit put on them that doesn't belong and a lack of sealant in places where it does belong. If you can't seal this with a dry gasket you are missing some other, serious problems.
Honestly doesn't matter. Just make sure the rim of the cover is nice and flat up against the diff. Add a little bit of blue thread sealer on each bolt. Send it.
LubeLocker gaskets and never look back!
You just opened another can of worms for me. It’s looking like I just might go that route since they have good reviews.
LubeLocker is the greatest thing since sliced bread, yeah it's a bit expensive, but it's reusable! Plus you get the best of both worlds!
Ease of use of a gasket, and a leak free seal of RTV, but without the mess, and you don't have to wait for it to cure.
I have them in both the front and rear of my Jeep and couldn't be happier!
Man thanks again I really didn’t want to think about doing this cover twice in case of a leak. I will definitely be buying that gasket instead.
Luckily this Dorman gasket was only $5.
Maybe I'm just headed but this whole exchange feels like an ad
Yeah, it does kinda look like an ad looking back at it. I am in no way affiliated with LubeLocker.
We used plain ole grease to coat fibre gaskets for oil pipeline joints and blanks, on tankers. That way they didnt stick to the flange and were reusable, and it made assembly easier if you didnt have someone helping you.
Watch out for the Chinese knockoffs. Garbage
Its worth it. Lubelocker or no gasket at all. Gasket + sealant is a no go. If no gasket just get anaerobic flange sealant like loctite 518. Ive done a couple differentials.
Yep don't know why anyone would use anything else. Unless they just don't know about em.
They operate a company out of the same building called Jim's Gaskets. They have been in business for decades and Jim's are the only gaskets reputable Harley engine builders use. They are absolutely the only gasket I would use in a hard to get to spot. The silicone bead makes a huge difference; especially when the surfaces are perfectly glass smooth and flat.
Advice to add a film of gear oil safe rtv to both sides. If you use standard rtv like others have mentioned it will start to leak after a while.
I thought RTV on these types of a gaskets wasn’t recommended? I’ve always heard it’s either one or the other. This would be my first time using a gasket on a rear diff cover.
My other trucks used RTV.
In a perfect world you shouldnt need rtv, in reality covers aren’t perfectly flat and it will help. I wouldn’t use the gasket personally unless you need it for ring gear clearance, but it won’t hurt anything to use both. The main thing is to use a gear oil safe rtv and follow the instructions.
A very thin amount on each side is all that's needed. I agree with the other poster; if it was new/perfect then probably ok. But a ultra thin amount on each side will help.
Just use the 90minute right stuff or Ultra and let it dry at least 4 hours. I like the 90minute right stuff as its usually good to in 30minutes if warm and an hour if cool.
Dont over tighten and pinch the gasket or it'll ooze out and not seal completely.
Me squinting : "I want to believe!"
Throw it away and use "right stuff" silicone. Gaskets are stupid and are a leak point. Silicone will never let it leak. The dealership doesnt even use a gasket anymore.
To answer your question you have it correct.
sillycone will never leak LOL
Have you ever used the "right stuff" by permatex. It will never leak. Im a 25 year mechanic and its the greatest stuff invented. I will never use a different silicone again.
I have, it's good. I like the three bond stuff better though. I was just remembering when people would try to seal synthetic oil with the red rtv...didn't work worth a damn
Right stuff 1 minute is the best. I mean besides Honda bond or the gm stuff used to be really good too.
Yep, I've never used a gasket on a rear diff cover. And I use the Right Stuff exclusively.
1 face up and 1 face down
Doesn’t matter which side faces where. Clean both surfaces well, make sure it’s centered, and torque evenly. A light sealant can help, but flat and clean matters more than direction.
Sometimes, one side sticks and one side doesn't. Which side sticks? I'm guessing the side with graphics.
Shouldn't matter like everyone else is saying. It'll would probably be marked if it did or wasn't obvious.
If all holes line up you are good. No drain plug so you have to take cover off to do fluid service still!
Just throw it away and use some grease, she'll be fine 🙂
It doesnt matter. Either way is good as long as the holes line up. I personally give the whole gasket a coat of black silicone.
That way
Looks good. Send it
The non-leaky way
Sides with flats go on left and right
Yep. Just use the right stuff.
Lots of different info in here. What I would add is, it is very important that you DO NOT BLOCK those little rectangle cutouts if you do use silicone. Those holes have to be clear and if you look at the axle housing you'll see round holes that they line up with.
This is so oil can flow into the axle tubes and down to the wheels bearings to keep them lubricated. If you look at the cover you will see some indentations where as the oil gets slung around it funnels it through those holes.
I have see many bearing failures where either the gasket didn't have those holes or they gobbed way to much silicone on there effectively blocking the passages. You can do some google searches and find this is a very common mistake
Ok, now as someone who is a career mechanic. Most the time I would skip the gasket and just use silicone (my favorite is the permatex Ultra Grey for everything). If I did use the gasket I would coat the whole thing with a THIN (not thicker than a dime) layer of silicone. Just enough so I can't see the paper. Then I would install to a good cleaned and prepared surface, get all the bolts threaded in. Then tighten till they and all just starting to squish a little out, then final tightening with a ratchet.
Personally I don't like how small the oil holes are so I would be tempted to ditch the gasket or modify with scissors to better fit the flat surface of the cover. And the other thing that's important is that your cover is relatively flat and not bent (usually from prying the old one off) which can be sorted out on a good flat surface with a hammer.
Blue side down
I've learned that as an anxious person I make many things harder for myself by thinking about them too much.
Test fit it on both parts. Seems like the bolt holes lineup but the little slots are in different spots. So you know it fits on that part, but what does it look like on the other part it gets bolted to
If it's symmetrical, I can go either way. The printing on one side is just the branding for the gasket material.
Yes
The plug should be on the higher side.
The fill plug
It doesn’t matter
From what I understand the gears should not be submerged in lube and the magnet will only be useful at the bottom of the diff. So fill hole and magnet at the bottom.
Which ever way fits in the trash can better and then use rtv to seal the diff up. Ill use a gasket on anything except a differential. Every few years ill give one a shot and then a few months later remember why I don't use them when it starts leaking. Just my opinion use it if you feel like it.
The only reason I’m using a paper gasket here is because that’s what was on the old cover and it never leaked. Diff had something like 100k miles on it with the paper gasket before I opened it up. Only other trucks I’ve had I used RTV on the diff cover and they never leaked.
Here's an upvoted for being correct and getting downvoted anyway.
This sub is getting really bad nowadays.