CRANKSHAFT REAR OIL SEAL REPLACEMENT

Tools Required
J 41479 Crankshaft Rear Oil Seal Installer. See Special Tools.

Removal Procedure




Fig. 125: View Of Crankshaft Rear Oil Seal

Courtesy of GENERAL MOTORS CORP.

1.Remove the engine flywheel. Refer to Engine Flywheel Replacement.
2.Gently pry the crankshaft rear oil seal (1) from the rear cover.
Installation Procedure

IMPORTANT:
 Do not lubricate the oil seal inside diameter (ID) of the crankshaft surface.
 Do not reuse the crankshaft rear oil seal.



Fig. 126: View Of Crankshaft Rear Oil Seal

Courtesy of GENERAL MOTORS CORP.

1.Lubricate the outside diameter (OD) of the oil seal (1) with clean engine oil.
DO NOT allow oil or other lubricants to contact the seal surface.
2.Lubricate the rear cover oil seal bore with clean engine oil.
DO NOT allow oil or other lubricants to contact the crankshaft surface.




Fig. 127: Installing Crankshaft Rear Oil Seal Using J 41479

Courtesy of GENERAL MOTORS CORP.

3.Install the J 41479 cone (2) and bolts onto the rear of the crankshaft. See Special Tools.
4.Tighten the bolts until snug. Do not overtighten.
5.Install the rear oil seal onto the tapered cone (2) and push the seal to the rear cover bore.
6.Thread the J 41479 threaded rod into the tapered cone until the tool (1) contacts the oil seal.
7.Align the oil seal onto the tool (1).
8.Rotate the handle of the tool (1) clockwise until the seal enters the rear cover and bottoms into the cover bore.
9.Remove the J 41479 .
10.Install the engine flywheel. Refer to Engine Flywheel Replacement.

At least that's what the manual says. The large gasket is probably for the rear cover.

Dennis

 

CRANKSHAFT REAR OIL SEAL REPLACEMENT

Tools Required
J 41479 Crankshaft Rear Oil Seal Installer. See Special Tools.

Removal Procedure




Fig. 125: View Of Crankshaft Rear Oil Seal

Courtesy of GENERAL MOTORS CORP.

1.Remove the engine flywheel. Refer to Engine Flywheel Replacement.
2.Gently pry the crankshaft rear oil seal (1) from the rear cover.
Installation Procedure

IMPORTANT:
 Do not lubricate the oil seal inside diameter (ID) of the crankshaft surface.
 Do not reuse the crankshaft rear oil seal.



Fig. 126: View Of Crankshaft Rear Oil Seal

Courtesy of GENERAL MOTORS CORP.

1.Lubricate the outside diameter (OD) of the oil seal (1) with clean engine oil.
DO NOT allow oil or other lubricants to contact the seal surface.
2.Lubricate the rear cover oil seal bore with clean engine oil.
DO NOT allow oil or other lubricants to contact the crankshaft surface.




Fig. 127: Installing Crankshaft Rear Oil Seal Using J 41479

Courtesy of GENERAL MOTORS CORP.

3.Install the J 41479 cone (2) and bolts onto the rear of the crankshaft. See Special Tools.
4.Tighten the bolts until snug. Do not overtighten.
5.Install the rear oil seal onto the tapered cone (2) and push the seal to the rear cover bore.
6.Thread the J 41479 threaded rod into the tapered cone until the tool (1) contacts the oil seal.
7.Align the oil seal onto the tool (1).
8.Rotate the handle of the tool (1) clockwise until the seal enters the rear cover and bottoms into the cover bore.
9.Remove the J 41479 .
10.Install the engine flywheel. Refer to Engine Flywheel Replacement.

At least that's what the manual says. The large gasket is probably for the rear cover.

Dennis

Oh wow! Dennis, that's a ton!!

This helps a lot, although all the lubricate this side but don't touch this side and what not seems confusing. Pretty wordy actually. I'll finish getting the bell housing and clutch removed tomorrow and see what this looks like in comparison.

Thanks again,
Nathan

Oh... I'll be sure to snap a few pics...

 

I'm confused... do I just replace the seal? Or do I also replace the gasket on the back cover? See the picture with the red outline... On a side note, is this going to make a mess, as in oil leaking everywhere???

 

I went ahead and replaced the rear cover plate gasket as well. It appeared it may have been seeping slightly. It did leak some oil from one of the top bolts and then a few tablespoons worth once the gasket cracked loose. It was kind of cool to see inside the engine through the cracks and valleys!

Does anyone know the torque spec's on the rear cover plate bolts? Answer: Engine Rear Cover Bolts 18 lb ft

I installed the felpro rear main seal, it has this plastic disk inside of it that makes it really easy to slide on onto the crank shaft! It doesn't appear to be as deep as the OEM. Any idea if I let it stay flush with the outside rear cover, or push it all the way in until it seats? I don't think I should though, as going in to much farther may make it too hard to dig out.

Here's a few more pictures... Maybe they will help someone out... I've bitten off more than I can chew for now.

 

Apparently the felpro kit is worthless. Its already dripping oil from either the gasket or the seal! I was also told by SNL they are junk as well, so I got an OEM piece sitting in the car now. I'll be replacing it shortly. Also I was told to make sure and put rtv/silicone on the bottom corners of the rear cover!

 

. Nice I am doing the same chore as we speak! Good to know about the rtv. How much? And about how far from the corner in? I plan on putting the back cover back on tomarrow. Its kinds strange how the pan gasket re-seals itself along the bottom without sealant but yet you don't want it to sweeze and drop inside the motor. I'm new and learning!

 

Wow, great thread for info.

 

i was thinking about that, where do you mean by top edge?

 

Wish I had a good pic, but there is the flat piece that the plate sits on. There seems to be a small gap there, so I kind of smeared some sealant along that edge as well.

 

hmmm, cannot picture unless your talking about the flat edges on the bottom on the sides, and as you said above a light/thin layer along the very bottom flat surface,

 

I'd just smooth a good layer all along there, corners good and up maybe an inch or so. I'd cover the entire front, should get you pretty close to a good seal.

 

I just had to do this today when putting in the new clutch. I found this thread when searching for the rear cover torque specs.(thanks) I bought the new replacement seal from the dealer as well as the rear cover gasket. I also used the black RTV on the surface as well as caked on the bottom edges. We'll see how it all holds up.

Interestingly, the factory seal said "National" on it as in National seals and bearings...which is the same that Advance Auto sells.

 

Yea, long story short, I ended up finding out they were the same seal, the fel-pro and the one that GM sells... :slap:

After I totally slopped the rtv all over the bottom of the rear cover and the sides, I haven't had any seepage since!

 

Glad I found this thread...mine is starting to leak...good post.

 

Lots of info! Good thread

 

Howdy! More reviving...

Installing a new rear main seal/gasket/cover combo while I am swapping my clutch.

The service manual doesn't mention anything about installing an all-in-one piece, just individually. With that said, it says to oil the outer diameter of the seal before installing it into the cover. Since the combo comes with the gasket already installed, do I need to remove it and oil the OD, or just leave it in and install the gasket and cover as is?

To make things more confusing, these are the steps in the service manual:
8. Lubricate the outside diameter (OD) of the oil seal (1) with clean engine oil. (See question above.)
Do not allow oil or other lubricants to contact the seal surface. (Isn't this contradicting?)
9. Lubricate the rear cover oil seal bore with clean engine oil. (What is the bore, if not the ID, which was said not to be oiled at the beginning of this thread?)
Do not allow oil or other lubricants to contact the crankshaft surface. (Contradicting again?)

Thanks!

 

now i really don't remember when i did mine. i think with the current design seal, it's installed dry.

i think the service manual is telling you to use oil to install the seal in the cover, and leave the part that seals against the crank flange dry. you aren't installing a new seal onto an old cover, though.

if you're using the cover/gasket/seal combo, i would 'prolly disregard.

 

Thanks Hubes. Do you think I need to oil the inner face of the seal (towards engine) and/or outer face of the seal (towards transmission)?

FWIW I'm using the Dorman 635-000 alignment tool. The video at this link doesn't say anything about oiling anything, looks to be installed dry.

 

since you have an alignment tool, definitely use it. i never used a tool. i used GM part number 12639250 and and used the plastic insert to align the assembly with the crank. as you slowly draw the plate towards the engine the plastic insert pops off, but everything stays aligned. worked fine for me, did the one on my 5.7l many years ago as well as the 5.3l i assembled, no leaks. some folks put a dab of rtv in the spots where the cover gasket and oil pan gasket meet. some don't.

torque the cover bolts down first, though, in a criss-cross pattern. THEN torque those skinny AF, easy to snap oil pan bolts. (you have a torque wrench that does inch lbs, right?)

no need to put ANY oil on the seal if it's already installed in the cover.

 

since you have an alignment tool, definitely use it. i never used a tool. i used GM part number 12639250 and and used the plastic insert to align the assembly with the crank. as you slowly draw the plate towards the engine the plastic insert pops off, but everything stays aligned. worked fine for me, did the one on my 5.7l many years ago as well as the 5.3l i assembled, no leaks. some folks put a dab of rtv in the spots where the cover gasket and oil pan gasket meet. some don't.

torque the cover bolts down first, though, in a criss-cross pattern. THEN torque those skinny AF, easy to snap oil pan bolts. (you have a torque wrench that does inch lbs, right?)

no need to put ANY oil on the seal if it's already installed in the cover.

I'll use the alignment tool for sure then, I got the same part number with the plastic insert and was wondering what method would be best. Planning to RTV the two locations where the cover meets the pan.

And yeah those things look weak, in lb torque wrench on hand! Sounds like the cover bolts are only 18 ft lbs too. Good to know you went in a criss-cross pattern, service manual doesn't provide a pattern like it does for the flywheel and pressure plate.

Alrighty, no oil it is.

Thanks guy.