If it was level in both axis' on the jack then I'm not sure what's going on. You can probably get a gallon or more in if it's tilted, but it will probably shift harder than a *****'s heart. Regardless, the FSM specifies 2.6 quarts.

 

You can overfill it. Put 2.6qts in it and walk away. I overfilled mine like this and it can screw your clutch.

 

What are people using to seal the secondary drain plug? manual says crush washer on the primary and some kind of "sealer" on the secondary drain. However, none is specified as to what sealer should be used.

telflon tape?

 

^I use a little Teflon tape. It's a pipe thread into an aluminum case, just be careful not to overtighten.