I have a chevy G30 van that is a winnebago rv it has a 350 motor in it and the rear main seal is leaking.I am trying to find out if it has a two piece rear main seal or the one piece seal.The biuld date on the sticker of the van says May 11th 1985 other that that i don't really have much more information on it.Also which is harder to change the one peice or the two piece seal.

 

a two piece rear main is going to be easier to change than a one piece. on a 1985 350 it should be a two piece rear main. but it could also be a one piece. it really depends on whether it is a 2 bolt or 4 bolt main.