rear main seal... change

92sclikenew

92sclikenew

Registered User
how bad is it to put a new rear main seal in when the trans out and the motor in.

mine is a little leaky.. and my trans is out i know it can be done on some cars but can it be changed on a sc with the trans out motor in...
 
yeah, the seal can be changed with the trans out. i did mine the first time i had the trans out and was changing the flex plate. even after changing mine, it still weeps a little. the second time i pulled the trans out, i noticed a single drop of oil on the rear edge on the bottom of the oil pan. i figure that when i swap in a 5 speed, I'm gonna have to sleeve the crank. bummer :(.
 
cmill95 said:
yeah, the seal can be changed with the trans out. i did mine the first time i had the trans out and was changing the flex plate. even after changing mine, it still weeps a little. the second time i pulled the trans out, i noticed a single drop of oil on the rear edge on the bottom of the oil pan. i figure that when i swap in a 5 speed, I'm gonna have to sleeve the crank. bummer :(.
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idk much about this what is sleeve'ing the crank... it only drips once in a while.. and just leaves the pan wet...

i was just thinkin of pulling the fly wheel off and running some silacone around the edges of the seal and the oil pan...
'
 
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sleeving the crank is where you place a thin bushing on the contact surface of the crankshaft where the RMS contacts. it's usually used to "renew" a round sealing surface.
about using silicone, DON'T! all you are going to do is waste your time and material. go and get a new seal, take a small flat tipped screwdriver and being careful not to scratch the crank, gently pry the seal a little at a time going around the sealing area. once you have it out, check your new seal to the old seal to verify it's the correct part. some say coat the lip of the seal with petroleum jelly or oil, I've installed them both dry and lubed. the ones that are going to continue to leak do so which ever way they're installed. place the seal on the crank and push it until it starts, then with a drift punch or similar flat faced punch, set it a little at a time being sure not to get it too far on one side or another till it's set as deep as the original.
I've seen other ways, but that's how i did mine. once it's done you'll think "that wasn't so bad".
 
Add some RTV black where the seal sits, the metal rim around the outside once you have cleaned it up real good with some solvent. I re-sleaved my 96 3.8 and no leaks as yet but they recommend that you use lock tight and the install tool. You only need to use the sleave if you have a groove in the crank where the rubber part of the seal rides on the crank.
 
i wish that was the case in my situation. no groove detected with the old seal out. no damage during R&R, and it weeps. oh well :confused:.
 
mine weeps a little after the new seal, i put a little silicone around the edge of the seal no more weeping:)
 
i might try that when i do the 5-speed swap, but a week ago this info/thread would've been great.
i guess I'll chalk that up to my luck with timing. DAMN, DAMN!!! :(
 
Changing rear main seal

I just wanted to share an easy way I found to pull the rear main seal with only taking the tranny out. I drilled two small holes through the sheet metal part of the seal and screwed in a couple machine screws a couple turns. This gave an easy place to lock onto with a couple pry bars, and it popped right out.
I thought this was a good way because it keeps you well away from the surface on the crank were the seal rides.
 
I thought I remember hearing that a rear main seal off a newer 4.2 L model fits the SC engine and also is better at preventing oil seapage than the actual seal for the 3.8 model. I think either Dave Dalke or Bill at SCP told me that, I can't remember for sure though. I gotta do mine soon again too since it's seeping pretty good only after about 5000 kms. I installed a replacement seal for the 3.8 L SC motor but will probably try a 4.2 L seal the next time I pull the tranny since my second gear synchro is acting up again too already :(
 
SK_BlownThunder said:
I thought I remember hearing that a rear main seal off a newer 4.2 L model fits the SC engine and also is better at preventing oil seapage than the actual seal for the 3.8 model. I think either Dave Dalke or Bill at SCP told me that, I can't remember for sure though. I gotta do mine soon again too since it's seeping pretty good only after about 5000 kms. I installed a replacement seal for the 3.8 L SC motor but will probably try a 4.2 L seal the next time I pull the tranny since my second gear synchro is acting up again too already :(
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thanks for that info

let me know if you find out for sure... or if anyone else on here knows for sure.. and that it works better..
 
Let's bring this back from the dead.

At the parts store they show 2 for our cars. The improved design is rubber and the other shows to be Teflon. Which would be better? They say the rubber is improved but is it improved over the teflon or of the old rubber??

And I see mention of using the 4.2 seal in place of the original in this thread. Is it even better still?

I has a leak and while I have the tranny pulled I am changing it.

Edit: Shows same parts numbers for the 4.2. So only question is improved rubber or Teflon.
 
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Get the more expensive one.. Its the one that they don't recommend using a sleeve with. Thats correct, they don't want you to use the sleeve. I have one that I did with sleeve and the normal rubber seal and one where I used the PFTE seal.. I can't recall any leaks with either setup.
 
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