rear main seal - one or two piece?

[kikkegek]

guys.

can anybody tell me if my Burb has a one or two piece rear main seal?

I have SB350 in my 1986 K20 Suburban.

and I need to replace it, because it is leaking oil!

[kikkegek]

neder mind

Two-Piece Vs. One-Piece Seals
From 1955 to 1985, all small-block Chevys were built with two-piece rear main seals. Unfortunately, this seal design is prone to leaking, so in 1986, GM redesigned the small-block with a one-piece rear main seal. This changed the rear crankshaft flange design to accommodate the one-piece seal.

[kikkegek]

he guys.

still got another question.

How hard is it to replace a one-piece rear main seal?

[BigBlocksRule]

Unbolt the bellhousing/tranny and slide it back, unbolt the flexplate/flywheel and you're there. I usually remove the fixture that holds the seal so I can swap the seal on a bench, but I understand it can be R&R'd in place.

[kikkegek]

Originally Posted by BigBlocksRule

Unbolt the bellhousing/tranny and slide it back, unbolt the flexplate/flywheel and you're there. I usually remove the fixture that holds the seal so I can swap the seal on a bench, but I understand it can be R&R'd in place.

he thanks man!

can I move the tranny enough to be able to remove the seal?

also, I have a 4WD...so is just sliding back the tranny enough? or do I need to unbolt the transfer case too?

[BigBlocksRule]

Get some all-thread about a foot long, two pieces. Once you remove the bottom bellhousing bolts, thread these in. Put a pair of nuts, locked together, on the back end. Once you get everything loose, you'll be able to slide the tranny back along the all-threads (with the help of a jack, of course, so that when you're finished, everything will slide straight back in place and you won't have to fight it. As for the transfer case, I'd leave it connected to the tranny, unplug any wiring and take the front drive shaft loose. That's going to be a heavy tranny/case, be sure you have a good jack and that it's balanced and tied in place.