Rear main seal for 305E

[jmfurgason]

Looking for part #s for 305E rear main seal part# and supplier. Thanks

[gmcjuniorvan]

Gmc part number 2367461
Fel-Pro BS 40048

https://www.rockauto.com/en/catalog/gmc,1963,1000+series,5.0l+305cid+v6,1340750,engine ,crankshaft+seal,5604

[tbucketnut]

To do that kind of a job ie R&R rear main, put the best seal you can find in there. Highly recommend you contacting Olson Gasket and sourcing their rope seal. It is made out of better materials for leak safe installation. If you want to settle for the felpro one I have an extra and will send it to you for free.

https://www.olsonsgaskets.com/

[jmfurgason]

Thanks for the info, much appreciated. I will call Olsen Gasket one time replacement sounds better. Merry Christmas to all. JMF

[jmfurgason]

Received rear main seal from Olsen Gasket,thanks" tbucketnut" is it necessary to pull motor or Crankshaft to replace rear mail seal?? or can it be replaced by pulling oil pan and flywheel cover?? Thanks to all Merry Christmas and prosperous New Year.

[gmcjuniorvan]

10038Received rear main seal from Olsen Gasket



I have a friend with a 305 who has to change his rear main seal. Did you receive all the seals for the job from Olsen Gasket?

Seals for the rear main and bearing cap.

[jmfurgason]

Yes i received a complete set 6piece rear main seal kit.

[James]

Received rear main seal from Olsen Gasket,thanks" tbucketnut" is it necessary to pull motor or Crankshaft to replace rear mail seal?? or can it be replaced by pulling oil pan and flywheel cover?? Thanks to all Merry Christmas and prosperous New Year.

They make a tool for replacing the rear seal. Amazon has one, there might be other:
https://www.amazon.com/gp/product/B0002SRCJW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

[tbucketnut]

I personally would not do an in vehicle rear main R&R at my age.
Couple reasons, the main being the bellhousing must be removed of course and that is the main support of the rear weight of this very heavy engine. I definitely would not hang this engine off the front motor mounts, that would be a Darwin award winner if the vulcanizing let go of the motor mount biscuit.
Then to consider dropping the pan and then the main caps to drop the crank, oh god then to try and fish the upper seal out. Total F that. Bring out the engine and give it a cleanup and spray can rebuild, get the engine on the stand and inverted and do it correctly that way IMHO. Im going to be 65, and have done a rope seal in the chassis on a smallblock chevy and still have nightmares of that one.
Steve

[George Bongert]

I personally would not do an in vehicle rear main R&R at my age.
Couple reasons, the main being the bellhousing must be removed of course and that is the main support of the rear weight of this very heavy engine. I definitely would not hang this engine off the front motor mounts, that would be a Darwin award winner if the vulcanizing let go of the motor mount biscuit.
Then to consider dropping the pan and then the main caps to drop the crank, oh god then to try and fish the upper seal out. Total F that. Bring out the engine and give it a cleanup and spray can rebuild, get the engine on the stand and inverted and do it correctly that way IMHO. Im going to be 65, and have done a rope seal in the chassis on a smallblock chevy and still have nightmares of that one.
Steve


Greetings, and Merry Christmas, Steve!

I agree that doing an engine in chassis rear main seal would be a rather difficult job and challenge. Better to REMOVE the engine from the chassis and put it on a (HEAVY DUTY) engine stand where it can be turned over bottom side up to do the job PROPERLY! That way, you will avoid making a costly mistake of improper seal installation, and an UNFIXED rear main seal leak!!