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such thing as a heavy duty rear main?

896 Views 7 Replies 3 Participants Last post by  BALLSS
so i replaced the rear main already and still have a leak coming either from it or the new pan gasket. either way im dropping everything agian to inspect it. i got a drip from the dust seal so im sure its the rear main. i got one from good ole autozone and it doesnt work..go figure. anyway is there a heavy duty one out there that is a better quality? thanks
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there's only one thing i can think of to explain a good quality seal that leaks that quickly -- you didnt properly inspect the crank surface for damage or wear marks from the old seal..
i scraped off the old gaskets and cleaned the surface it sits on.
the RMS I bought at Autozone is a FelPro...which is a very good seal. They make 2 types, one rubber and the other Teflon. Get the rubber one. If you installed the Teflon one with oil/grease it can leak. Teflon seals need to be installed dry

RMS leaks are not common. typically the rear intake gasket or oil sending unit leak and migrate down making it look like a RMS leak. Also the oil filter adapter can leak .

If you are tearing this apart again (big fing job) than really confirm wtf the leak is coming from. I used a oil dye kit to find my leak that I thought was RMS. It was the RMS adapter plate seal that was leaking which requires the pan be dropped also to remove it.

Confirm there is no wear groove on the crank where the seal rides on.
i know its in the main because i have oil inside my bell housing. when i popped the slave off it was dripping and it drips out the dust seal obviously too.
i know its in the main because i have oil inside my bell housing. when i popped the slave off it was dripping and it drips out the dust seal obviously too.

just because the oil is inside bell housing does not mean it is RMS. Could be but rear intake, oil filter adapter, RMS plate and oil pan are also areas wher leaks "get inside behh housing"

If you feel it is RMS and you replaced and it still leaks....you either FU the seal install or the leak is from one of the other sources.

was the crank gauged or have a wear indentation where RMS hit it?
im never looked nor do i really understand what your talking about? where is that going to be at
when you removed the old RMS, was there a groove on the crankshaft where it rides against the seal?

there should not be but

the crank end should be polished smooth spotless. grease the new RMS and install so you don't fold the lip under. twist it some as you slide it on then set it in by taping in circular pattern until it is flush

there is a "install" tool for RMS that makes it VERY simple but you can do it without one
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