Any kind of pipe dope, even the stuff regular plumbers use is O.K. The liquid teflon Permatex is probably the best though. Teflon tape is not great to use... the strands can end up in the cooling system. Plus it can cause thin-wall aluminum housings to crack.
agree with the "Permatex liquid Teflon," probly the best all around thread sealant I `ve ever used. And I have probly screwed more threads together than 90% of u all put together.
I have a bottle of it in my garage------old and getting pasty.
