rear main seal

[Steved]

This week my check oil light came on. Checked the oil and it was alittle low. Added half quart and all was well. However I needed an oil change anyway so my mechanic showed wear the oil was going. The rear main seal was leaking as was the intake manifold.Anyway he said the price tag would be over $800. Yikes!!! Would tightening up the bolts around the rear
main seal help or could I cause more problems? Is the intake
manifold gasket replacement a major job?

 

[Brian1]

How did you see the rear main oil seal without taking the tranny and/or flywheel off? Remember the oil will eventually end up on the bottom of the engine because of gravity so you may think it is your rear main but it could be the oil from the valve covers that you see. Changing the valve cover gaskets is not that hard at least on the driver side. On the passenger side there is alot more stuff in the way. Try tightening the valve covers first and wash your engine off on the underside and sides. Look where the oil is coming from to see what your real problem is. Also, don't always trust the check oil light. Mine always goes off after the car has been siting at an angle. Good luck and I hope this helps.

Also, welcome to the site!

 

[rockylaurence]

I got the same leaks

I have had the rear main leak eversince I bought it new. However, I identified another leak at the rear of the intake a little while ago. I've been living with it over the years because it wasn't that bad but now I'm losing 1-2 quarts every oil change cycle. Fixing the leaks will provide the opportunity to do a valve job and maybe a Camm. Sounds like a good excuse to tell the wife anyway. Ha!

 

[Bronco_bill]

Intake

When I rebuilt my motor I also had the intake leak but I rebuilt the entire motor. I was told that the 4.0 is prone to intake leaks and found out when I put it together and had to add oil every day not to mention the smoke when I started it. The problem turned out to be that the shop slightly decked the block. Normaly when I build a motor I ditch the intake end seals and use a bead of black silicone in its place. I have found that with the high powerd motors that i have built blow out the end seals in about week and this permantly cures the problem. Back to the explorer, When I was asembling the motor I noted that the end intake seal was one piece and it looked good so I used it. It turned out that the end seals held up the intake allowing oil to enter the cyls. I got a new intake set and cut the end seals out used the silicone trick and have had no problems since.