Silicone/RTV choice for engine gaskets

[TexasRoadRunner68]

I have mopar and permeated brand RTVs. I have also seen rave reviews for permatex right stuff. Any thoughts? I am mainly curious what works well for oil pan gaskets, water pump gaskets, around the valley pan etc.

 

[Outsider]

Permatex RTV Black, oil resistant as advertised. Did the intake and the valve covers on the strip/street Dart last year. Ran it all summer at the track and hit 240 deg a few times hot lapping it at the strip, and drove it about 1,200 miles on the street. Just changed the intake and re-did the cover gaskets for this season because it's another year, and the seal was still good and took some effort to scrape off. Used it again.

 

[RemCharger]

I use the ultra black on all engine builds.

 

[Kern Dog]

This stuff sealed up valve covers and oil pans when nothing else did.
Be warned: It makes the parts very difficult to remove later.

 

[70ChargerRT]

This stuff sealed up valve covers and oil pans when nothing else did.
Be warned: It makes the parts very difficult to remove later.

View attachment 1453927

The black Right Stuff is the best stuff!!! I did use the permatex water pump and thermostat rtv only on those 2 and that’s it.

 

[91r/t]

This stuff sealed up valve covers and oil pans when nothing else did.
Be warned: It makes the parts very difficult to remove later.

View attachment 1453927

Yea I have never used it personally but that shits like the end all be all to sealing it up I hear. My buddy struggled to get his oil pan off after he stuck it on with that.......Positive though it didn't leak!

 

[dvw]

I use Ultra grey. Never leaks. If its a large surface (like an oil pan) use a gasket with it. If not it'll be tough to diasemble.
Doug

 

[91r/t]

^^ Vote for Ultra grey as well.

 

[Tman100]

I use Ultra grey. Never leaks. If its a large surface (like an oil pan) use a gasket with it. If not it'll be tough to diasemble.
Doug

I also vote for ultra grey. Just a note it’s what Cummins used out of the factory in the 5.9’s. The eliminated the front timing cover gasket and stated to just use ultra grey.

 

[ruffcut]

Right Stuff gets my vote! ruffcut

 

[WileERobby]

I've been using this for over 50 years

 

[AR67GTX]

After some of the stories I’ve heard about Right Stuff and disassembly/cleanup I’m almost afraid to use it now. I’m sticking with gaskets and spraying them with a full coat of Permatex gasket sealant at the time of assembly. So far, so good.

FWIW - beware of Permatex RTV over 2 years old. That is what Permatex references for shelf life. When it overages it gets runny in my experience. It’s not unusual to find new product on the shelf that is already a year old. Check the date code. From memory the first number is the year such as 3 is 2023. The next alpha numeric character represents the month of manufacture - A = Jan. If I’m off on this someone will correct me.

 

[lewtot184]

if i don't want a leak i use permatex ultra gray.