Rear main seal

[Marv02]

How hard is it to replace the rear main seal and main seal plate.

I know I have to pull the trans and my is a 4X4.

I have done everything else hopping I do not have do the rear main seal but still have a oil leak.

I put a new oil pan gasket, New Oil Pressure switch new O ring on the Can positioning switch, new gasket on the oil cooler block off plate, Watched the valve cover gaskets when it running used a mirror on the top back side of the bell housing no leak also.

I not looking FWD doing this job but again I don't want to spend all the money for the labor either.

---------- Post added at 08:44 PM ---------- Previous post was at 08:38 PM ----------

I done a lot of pulling transmissions in the past not one of the jobs I enjoy doing.

 

[OR VietVet]

FELPRO kit #BS40640 $16.10. Comes with seal and gasket for cover. The seal is mounted in the cover and slide over the end of crankshaft. Make sure when you remove old seal you do not nick the crankshaft. Clean area completely and use a film of grease on shaft when sliding the seal on.

 

[Marv02]

What kind of grease do you recommend.

I was planning to get a new main seal cover just in case that's a lot work might fix it right.

When I built my 383 for my Vett lot others said Felpro main seal are know to fail.

I normally use Felpro gaskets but if they have a track record of failure I not sure I want to take a chance.

FELPRO kit #BS40640 $16.10. Comes with seal and gasket for cover. The seal is mounted in the cover and slide over the end of crankshaft. Make sure when you remove old seal you do not nick the crankshaft. Clean area completely and use a film of grease on shaft when sliding the seal on.

 

[OR VietVet]

The grease can be just about anything. A silicone grease would be ok. You are just using a film of it. I have used FELPRO for years and stick by them. Some people also don't follow the recommended steps for prep when reassemble. The area must be DRY & CLEAN. Clean, clean, clean. Make sure you inspect the crankshaft with a light and mirror if needed. If you have a scratch or nick it may well leak again. That is why they developed the covers with the seal in them. To keep from having to dig the old seal out from around the end of crankshaft on the old design. When doing this you will also get a closer view of the back of the valve covers. When you do this I recommend changing the oil and filter if close to time and adding dye to reinspect with blacklight after about 1-2 days of driving.

 

[Marv02]

Thanks I take a close look at the mating surface before put the new on back on.

So you don't think I need to buy a new seal cover just clean it up and reuse it.

I don't want to do this job again.

If I have pull the trans every again it be time to install a rebuilt trans I planning to build a new one in the next 6 months and a new 5.3 soon after I want to be put them in when the SUV hit around 200K or so I at 157K now.

So it will go another 200K I don't want any more high truck or SUV payments ever again.

 

[ivin74]

is the change out of the rear mail seal a 1 man job or a 2 man job? i believe mine needs to be changed out to.

 

[Gzes]

More hands are always better. We usually have me and my bud dropping and me and 2 buds installing when we do transmissions

 

[ivin74]

I'm going to do it after the holidays.

 

[OR VietVet]

The more the merrier. I have done it by myself on my back but that trans was a B****. Always have one extra guy or girlfriend/wife around that gets beers for everyone. That is one important tool!

 

[Marv02]

It a one person job but you must have the right tools.
It should be a full days job.

I found the cleaning the parts before you put back together up take most of the time.