easiest way to change the rear main seal
 

so the 350 in my truck has a leaky rear main seal :waah:... im wondering what the easiest to replace it? do i have to pull the trans? or can i get away with just pulling the pan and and back main cap?

Re: easiest way to change the rear main seal
 

Assuming its not a later model engine with a 1 piece rear main seal, yes, you just drop the pan and rear bearing cap to change the seal. No need to drop the trans.
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Re: easiest way to change the rear main seal
 

easiest way i found was to drop it off at a good shop and pick it up after its done

Re: easiest way to change the rear main seal
 

thanks man!
:lol: something said to be said for doing it that way!, it is easier for sure, but im to cheap to send my truck into a shop for anything.

Re: easiest way to change the rear main seal
 

If it's in the '80 in the Blazer in your sig line... you won't need to lift the engine to get the pan out. Which it a good thing. But... the whole process is a PITA no matter how you do it.

Gary

Re: easiest way to change the rear main seal
 

I don't know about getting the pan off without lifting the engine on his truck.
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Re: easiest way to change the rear main seal
 

I've done a few rear mains in late 70's and early 80's (2 piece) trucks and didn't have to lift the engine. They were all 4x4's as well.

Gary

Re: easiest way to change the rear main seal
 

I just tore into it this morning and I got the pan and main cap off without lifting the motor, should have it put back together tonight.
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Re: easiest way to change the rear main seal
 

I've never done on on a 4x4 personally. I was just going by 2wd trucks.
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Re: easiest way to change the rear main seal
 

There's a guy in another thread who takes about making sure the timing mark is facing straight down. Apparently this places the crank in a position where the pan slides out once unbolted. My rear main is leaking like a sieve, and am planning on doing the seal replacement myself. I will let you know about the pan.

Re: easiest way to change the rear main seal
 

i never did that.. but it sounds like a good idea.. tell us how it works, best of luck!

Re: easiest way to change the rear main seal
 

They are trying to make sure that the counter wieght on the crank doesn't catch the pan as it slides back. It is fun trying to get the rear of the pan to clear the trans, baffle clear the oil pump and pickup, and clear the crank all the while bottoming out on the crossmember.:lol:

Re: easiest way to change the rear main seal
 

I never try to work around the oil pump. I drop the pan enough to get a wrench on the oil pump bolt and drop the pump into the pan.
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Re: easiest way to change the rear main seal
 

Yep been there 1st one I ever did lined up perfect second on was like what the heck why isn't this working raised the engine and got the pan off was like hmm that's why. Making sure the crank is lined up properly will make it a easy job unless you are working on a 4x4 the. It don't matter
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Re: easiest way to change the rear main seal
 

My 72 K20 isn't that bad. A jack and about 15 bolts gets the 3 piece crossmember out. You can then drop it straight down. Easiest one I have ever done. Pan easy, realligning the crossmember is a PITA due to slight frame twist (old age, not damage)!

Re: easiest way to change the rear main seal
 

Hopefully you will roll the seal through so it's sticking out an 1/8th inch or so otherwise you might be right back in the same situation. In other words, don't have the where the 2 halves of the seal line up with the 2 halves of the main cap. That is where oil wants to leak under pressure.