Sealant for Oil Pan RTV or Anerobic

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I am working on a 2014-2018 series Chevy LS engine (aluminum pan) for a broken timing chain tensioner which was alsostarting damage on the oil pump, but in order to complete the job I had to drop the oil pan and there to do the job. I am ready to assemble and Alldata DIY calls for RTV or Anerobic Gasket sealant to be used for the oil pan an timing chain cover.

Is one better than the other? The factory stuff was fairly pliable and peeled right off but it also was leaking in a few spots. I was thinking of permetex ultra black but do have much experience with these.

Thanks in advance.
 
What about something like this? For me a real gasket is superior to either of those compounds. This one is rubber/steel, those usually are the ones that hold up the best.

I like real as well. I got excited when I saw this. However I typed wrong I called it an LS but it is the 6 cylinder LV3 and this wont fit.

Thx
 
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It doesn't look like there is a preformed gasket available for an LV3 judging by RockAuto. If you need the vehicle back in service more rapidly, anaerobic does not need a 24 hour cure time, but is more expensive by volume than an RTV like Ultra Black.
 
It doesn't look like there is a preformed gasket available for an LV3 judging by RockAuto. If you need the vehicle back in service more rapidly, anaerobic does not need a 24 hour cure time, but is more expensive by volume than an RTV like Ultra Black.
I am no rush to get it back into service just wanted something that won't leak, The factory applied sealant was as leaking front and back. Just wanted something that seals well and lasts.
 
It looks like you are stuck with RTV, I would use the permetex ultra black, it seems to be one of the most oil resistant RTV. Anaerobic seals are great but very demanding to apply properly so it doesnt leak. The biggest issue with it is once cured it can be very difficult to remove the part again when used on such a large part.
 
It looks like you are stuck with RTV, I would use the permetex ultra black, it seems to be one of the most oil resistant RTV. Anaerobic seals are great but very demanding to apply properly so it doesnt leak. The biggest issue with it is once cured it can be very difficult to remove the part again when used on such a large part.
Anaerobic isn't applied any differently than RTV. The prep process for both should be the same. Anaerobic has a much smaller gap fill capability than RTV so the two products are rarely interchangeable.
 
Use the ACDelco or any of the Japanese RTVs like ThreeBond 1207B(Toyota FIPG)/1217H(Nissan/Subaru). The American OEs are using similar gray RTVs as the Japanese.

Permatex is OK, but IME, their gray RTVs are closer to OEM but do need longer cure time. If you must go Permatex, go with the Right Stuff series. Not sure about Ultra/Optimum Black but the gray versions take a long time to cure.
 
Anaerobic isn't applied any differently than RTV. The prep process for both should be the same. Anaerobic has a much smaller gap fill capability than RTV so the two products are rarely interchangeable.
Agreed. RTV is better suited to stamped steel pans than anaerobic sealants are. Cast pans or other fixtures with machined rails and good, rigid mounting will tolerate a broader range of sealants.
 
Anaerobic isn't applied any differently than RTV. The prep process for both should be the same. Anaerobic has a much smaller gap fill capability than RTV so the two products are rarely interchangeable.
Anaerobic does not tolerate nicks, scratches, or any other sort of surface imperfection very well. RTV is much more forgiving. I ran into anaerobic sealer on a large Honda clutch cover, the thing was a bear to remove without doing damage. I do use it on Subaru oil pumps but for another reason.
 
Anaerobic does not tolerate nicks, scratches, or any other sort of surface imperfection very well. RTV is much more forgiving. I ran into anaerobic sealer on a large Honda clutch cover, the thing was a bear to remove without doing damage. I do use it on Subaru oil pumps but for another reason.
Surface imperfections are only part of the equation. If they are dissimilar materials that expand/contract at different rates, that could become an issue as well. The gap fill that is achievable by RTV is significantly higher than anaerobic. For example, max gap fill from Loctite 518 anaerobic is 0.25mm; max gap fill from 5900 (basically Permatex Right Stuff) is 1mm.
 
Thanks for all the suggestions!
Use the ACDelco or any of the Japanese RTVs like ThreeBond 1207B(Toyota FIPG)/1217H(Nissan/Subaru). The American OEs are using similar gray RTVs as the Japanese.

Permatex is OK, but IME, their gray RTVs are closer to OEM but do need longer cure time. If you must go Permatex, go with the Right Stuff series. Not sure about Ultra/Optimum Black but the gray versions take a long time to cure.
The OEM stuff I scraped of was gray and still very pliable. Did not stick well, It was easy to scrape it off. Larger chunks would just come off using a fingernail.
 
Thanks for all the suggestions!

The OEM stuff I scraped of was gray and still very pliable. Did not stick well, It was easy to scrape it off. Larger chunks would just come off using a fingernail.
Definitely RTV. Anaerobic sealer looks kinda like melted sugar glaze on a baking sheet.
 
Thanks for all the suggestions!

The OEM stuff I scraped of was gray and still very pliable. Did not stick well, It was easy to scrape it off. Larger chunks would just come off using a fingernail.
I think all RTVs are like that. I was able to scrape off the OE Toyota stuff with a Delrin razor blade. I used Permatex Right Stuff 90 Minute gray for a timing cover reseal on a Toyota after screwing up the first try with Optimum Gray. The sealant was cured in some spots - but it was still soft and wet on the lower areas after 20 hours.

Also, Toyota’s ThreeBond RTVs are acetone cured, they offgas acetone during cure. Permatex ones are oxime cured, they are aerobic and need oxygen and humidity to cure, so is ThreeBond 1217H used by Nissan - but the cure times are wildly different.
 
I just saw a tech tip video from permatex and they claim the "synthetic" permatex is to be used in applications with synthetic oils.

Is this more marketing?
 
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