: latest lower end seal job procedure

05-03-06, 10:08 PM
Just curious if anything is new on the lower block seal job.
Im also debating the payoff considering I could lose a couple
of lower end threads while doing so.
Also wondering if I can use the newest timing cover/front seal
and rear main seal on a 95.
Do they make a speedy sleeve for balancer?

05-04-06, 06:18 PM
I see that no one has responded so Ill add some more to it.

the rear seal was revised from a 9 mm to a 12mm,assuming thats the width.
Also in mid 98 was a change to different timing cover and gasket
Will the revised timing cover and gasket and rear seal work on a 95?
Have you had success with using the factory block seals and GM gasket maker
as the tech bulletin suggests.
My 96 was done at dealer 7 yrs ago and still no drips.

05-04-06, 11:05 PM
Yes, you can use the wider rear main seal on a 95. It sets slightly deeper in the block and covers the lower crankcase side seal intersection point completely. Use RTV at that side seal intersection regardless for added insurance.

The aneorobic sealer added to the lower crankcase joint will definitely help with the lower crank case sealing. It acts as a redundant seal to back up the silicone beaded seal in case of a scratch or some surface defect.

The block changed in 98 slightly at the front. An revised engine mouting bolt at the right front of the block caused the profile change....not a sealing issue. A 98 or later cover/gasket will not work on an earlier block. There is no reason to try this anyway as the seal is the same....just a slightly different pattern due to the cover changing shape slightly to clear the new mounting bolt for the revised mounting in the (new) 98 STS.

05-05-06, 05:08 AM
The rear seal I have is for a 2003.Will this work?
I looked again at the upper/lower block joint and dont think
its worth it to reseal,not any wet sepage there,just some that appears to be with age(130K).
I got the front cover and seal on ebay as a package as the front cover on mine does leak somewhere on gasket area.
I want to replace the front seal but it appears to be tricky as the stamped metal timing cover is very flimsy.
Im also going to replace the oil pan gasket as it does also appear to have a drip. Then its bolt this back to the replacement 99 tranny and install the whole mess.I had to change some internal parts for the 99 trans to work on 95 PCM.

05-05-06, 06:13 AM
As long as you have it that far apart I think I would be inclined to replace the manifold plate. I replaced the oil pan gasket, installed the engine and as soon as I fired 'er up the thing was still leaking. After a minor meltdown I dropped the cradle and fixed it right. I'll be happy to share any details if you require :)

05-05-06, 05:38 PM
Cant that be accessed easily from above?
I think Ive got it figured out what to use where.
I went to local dealer and parts guy was real helpful.
I can use the latest revision rear crank seal,dealer says its all they stock
and use it on all models.
The timing cover has changed and wont work for a pre 98.
I bought a new gasket and seal for my 95 timing cover.
I also bought a new pan gasket but wont get into the upper block
half seals as its really pretty good considering 130K.
Please tell me more about the "minor meltdown"
Was hoping to get away clean with just a couple of seals and tranny replacement.
BTW Chevelle,thanks I would have found that out when I put one gasket over the other
but its really obvious when I put the 1st design gasket on top of 2 nd design cover.

05-19-06, 08:53 PM
All back together and it purrs