I got a Hastings transmission filter and the included gasket is flexible material. It looks like black and tan flecks.

Does it require a sealant for installation or does it go on dry?

 

Use sealant on the pan and then put gasket on the pan, sealant will hold it in place, no sealant is needed on the transmission side of the gasket

Don't over do the sealant because when you tighten up the pan it can squeeze out into the inside and it will form little ***** of sealant that can drop off and clog the filter, so thin layer

The pan is stamped steel so will have imperfections in its gasket surface, which is what the sealant helps with, fills in the imperfections
The transmission side is flat and true, assuming tou cleaned it, lol, so doesn't need the sealant but up to each DIYer to do what they think is best, as long as you don't over do it you can use sealant on any gasket both sides

The transmission pan has no pressure inside, its vented to the outside air at the top of the transmission, so gasket is just holding back the ATF from gravity leaks

 

I must tell you how the controlled, back of pan pre-dribble went.
My gasket wasn't affixed to any surface. The unit leaked as I loosened the bolts.
It allowed the flow to begin straight away. This created no problem.

The gasket had 2 small discs of metal on opposite sides of each of the 18 holes.
They were 2mm in diameter and 1.5mm high and served to prevent crushing. Impressive construction.

The new one absolutely needed to be held. Permatex Ultra-Black. It's what I intend to use on the rear diff cover.
What's that 1/4" metal tubing pointed down at the pan's left side?

 

Wonder if the first one was reusable. I've used LubeLockers on a few trannys and diffs and they work great. You can reuse a few times (3-5x) too.

 

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