Not enough clear information ! - Rear main seal on WHAT - ? ?
Yep, they have one. 1986 and older has a two piece rear main seal. 1987 and up has a one piece rear main seal.
how do you change a rear main seal in a Chevy 350 motor
remove transmission, remove rear main seal, install new rear main seal, install transmission.
Remove transmission and replace the rear main seal
does a 93 f150 have a 1piece rear main seal
You remove the transmission, and the flexplate(flywheel) to access the rear main seal.
how is the easiest way to change a rear main seal in a 460 ford
If it is newer then a 1986, yes it doe's have a 1 piece rear main seal.
Rubber.
dont do it
Water can not leak from the rear main seal, only oil. Most likely there is a leaking freeze plug near the rear main seal dripping water onto it.