N_Jay

About to do teh Transmission fluid change and the kit is missing the TC Plug sealing washer (Crush washer).

Wondering if anyone thinks it is a bad idea to substitute a hydraulic sealing washer.

01blackhawk

I wouldn`t take the chance for a tiny little seal, I`m sure you can find one to make it work if you buy a variety pack from a Auto parts store. Even Amazon can deliver overnight.

Max Blast

You’ll be fine.

N_Jay

That's what FCP said. (not their fault, it was missing for a Viaco kit.)
I would have them ship a replacement, but want to get it done this weekend.
I have an good assortment fo metric hydraulic seals.

For those who don't know, these are the modern replacement for the crush washers in banjo fittings.