Hi guys,

I have an oil leak that I first suspected was the rear main seal. I get oil leaking at the rear of the motor, front of the trans while driving and shortly after parking. Once it is parked for a few minutes the dripping stops. So I pulled the inspection cover off the front of my C-6 and there is no oil inside the trans. The flywheel is dry. There was just a bit of oil puddled in the bottom, but being that the cover is not water tight by any means, it may have just run in from the outside. So my question is, if there is no oil inside the trans bellhousing, or on the flywheel, then it is most likely NOT the rear main right? That would point me to oil pan gasket or valve cover gasket. I got under and started cleaning to help locate the leak. Any tips to help find it would be helpfull. Since any of these jobs are not minor, I would like to be sure first. So am I right in guessing the rear main is probably ok?

 

From what you say i would have to agree that it is not the rear main, you have already started in the right direction. Cleaning the rear of the engine and aroundthe sides on the back and up around the valve covers. Then you sould be able to start the motor and watch for leaks. Good hunting.

 

If its dripping id check the valve cover gaskets, slide under it with a good light, and look up at the back side of the block at the valve covers, could possibly be rear intake gasket. DW

 

Ok got it hosed down with degreaser, let it soak and shot it with the hose. I drove it a bit and will get under it in the morning and see what there is to see. I'm just glad its not the rear main. I did not want to drop the tranny, as my bronc doesn't fit in the garage and the driveway slopes, so I have nowhere to set up where the trany wont roll away on me. Thanks for the tips guys.

 

check the oil pan bolts. had the same prob with my 96 sport and it was loose oil pan bolts in fact two were missing replaced them and re-torked the bolts and leak went away.

 

it sounds to me like the old trick me is in efect here also. i thought my rear main was leaking and it was the oil pan gasket. not a fun job but better than removing the trans. ford gives 6.5 hours to replace the pan gasket. it took me seven hours with a torch to remove the ex haust pipes. dw2455 does have a point i to would check the valve cover gaskets but i dout that they are leaking. yes if the torque converter is dry and it is dry inside the bell housing the rear main seal is not at fault. ford now makes an upgraded gasket for the oil pan but it is rather expensive around 60.00 dollars the , depending on year, stock gasket is either 8.00 dollars or in my case on a 91 5.8 it was 28.00 dollars. just make sure you get it troubleshot correct because it really stinks to do the job twice. good luck and work safe so you can enjoy your ride when your done.

 

also the rear main is a two peice unit you have to drop the crank to replace it been there done that lots of fun.

 

If you can get one of those little mirrors on a stick like the dentists use, you can use it and a light to find leaks higher up on the back of the motor. If the valve covers or dipstick mount are leaking oil, you may not see those spots otherwise. Just remember that oil does not run "uphill" but will leave a trail down the side of the block that you can trace to the source. I had several leaks on my motor when I bought the Bronco, and the engine had just been rebuilt.

 

i believe that on the later year 5.8's the rear main is a one piece seal and the trans has to be removed to install it . if it is a 2 piece seal you do NOT have to remove the crank to install but you do have to remove the oil pan to install it so you can remove the main bearing cap in the rear of the engine so you can slide the new one around the crank. but i doubt that it is your rear main if there is no oil inside the bell housing and the converter is dry.

 

beg your pardon bojo but exactly how do you remove the top half of the old seal without atleast dropping the crank down? i would love to learn your short cut.

 

I don't know about dropping the crank, I have to loosen it to let it fall a little. The best to find a leak is to follow the trail, like someone said oil doesn't travel uphill. The highest point up on the engine that you can find it is the sorce of the leak.

 

im sorry i should have clarified my self when i said dropping i ment just a little. sorry

 

loosen all the main slightly, roll the old one out and the new one in. DW

 

bofo was making it sound like all you had to do is take down the #5 main and slide it in. when i rebuilt my bottom end the top seal was a bear to remove no such thing as just sliding.

 

i meant exactly what dw2455 said . i thought that you meant to remove the crank. sorry for all the confusion