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.
does a 93 f150 have a 1piece rear main seal
Remove transmission and replace the 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.