T90 gasket sealer

[Penny]

Hi, can I please get suggestions on the right gasket sealer for the T90 and the D18?

[bmorgil]

Hello Penny, I am a big fan of "Aviation Form a Gasket". https://shop.advanceautoparts.com/p/permatex-aviation-form-a-gasket-no-3-sealant-4-oz-80019/7740018-p?c3ch=PLA&c3nid=7740018-P&adtype=pla_with_promotion&product_channel=online&store_code=&gclid=CjwKCAjwnef6BRAgEiwAgv8mQbqJHk4VCHHIpKk7Y05C 0s110EzJTBQVGGO7NZ6cSvl3FMnXspIp6BoCeRsQAvD_BwE&gclsrc=aw.ds

On the shims for the output bearing on the 18 use "High Tack". https://shop.advanceautoparts.com/p/permatex-high-tack-gasket-sealant-80064/7160164-P?searchTerm=permatex%20high%20tac

Most T90's leak at the front counter shaft to case and at the bolts that penetrate the case. I use Black Silicone there and on every bolt that penetrates the case to the lube (sparingly). They leak like crazy there. The Dana 18 usually leaks from the shims and also needs the bolts that penetrate to be sealed. There will be endless drips from the bolts if they are not sealed. These are often referred to as "wet Bolts" and rightly so. The shift rail seals and plugs also need a little attention. Careful installation of the seals or they cut. The plugs are known to fall out. Red Loctite is required.

[gmwillys]

Welcome Penny,

I like to use Permatex Shellac. Most of your auto parts stores sell this on the shelf. Let it tack up when applying, then assemble.

https://www.permatex.com/products/gasketing/gasket-sealants/permatex-indian-head-gasket-shellac-compound/?locale=en_us