rear main seal?

[iamdave0887]

I had the truck up on the lift at school last Thursday, and noticed that the back of the oil pan was moist. The truck never leaves a drop of oil in the driveway.

At the recommendation of another member i cleaned out the CDR valve as i didn't have the $$ to buy a new one at the moment but the current one has less than 15K miles on it. The CDR was filthy inside and now is much cleaner.

I was told the CDR valve can crud up when changing from conventional oil to synthetic oil. I switched from Rotella T 15w-40 to Amsoil 15w-40 2-3 oil changes ago(i go 3K on a filter and 6K on an oil change). I'm due for another change now and this will be my 3rd change running amsoil. I'm going from a Wix filter to an Amsoil filter this time as well. Could the amsoil have crudded up my CDR as it was cleaning everything out?

I know with a worn out CDR you can get front and rear main seal leaks. I'm curious as to if the dirty CDR caused my leaks or if i need to swap out the rear main seal? I bought a seal, but really don't feel like dropping the trans if i really don't have to.

There oil pan wasn't dripping oil, but was slightly moist(had a shine to it).

when it started i wouldn't loose more than 1/2 a quart over 3-4K miles.

I've got to get the truck on the lift to change the oil tonight, but i'm curious if i should hold off on the oil change and do the rear main first? As of right now the truck's got 175,7xx miles on it.

thanks guys.

 

[DennisG01]

While you've got it up there, and before you drop the tranny, look a little further and see if the leak isn't coming from where the turbo oil return line dumps back in. It's about a 3" plate - IIRC - with about a 1/2" nipple angling up. The black rubber return line simply slips on and is held in place with clamps. See if it ain't coming from there. Just tighten the clamps and you should be good.

 

[iamdave0887]

While you've got it up there, and before you drop the tranny, look a little further and see if the leak isn't coming from where the turbo oil return line dumps back in. It's about a 3" plate - IIRC - with about a 1/2" nipple angling up. The black rubber return line simply slips on and is held in place with clamps. See if it ain't coming from there. Just tighten the clamps and you should be good.

I tightened them up best i could when i was under there. strange thing is there's crud all around that tube. Its absolutely caked in crap, which leads me to believe that it was leaking from there at some point, or it still is. That tube will come off tonight for a good look over after removing the crud, to check for cracks or pinholes.

My valve covers were leaking for a bit, but i tighten those and rechecked them, and all bolts are tight.

Its not even a really big leak, my main concern is that if it gets worse all of a sudden(i tend to have that kind of luck).

 

[DennisG01]

I know exactly what you are talking about - I had exactly the same thing happening to the front of my oil pan. Unfortunately I can't tell you if the problem was the turbo return line or the rear seal. I fixed both at the same time. But, so far it hasn't come back.

 

[packratt]

If the dampness is drivers side rear check that you don't have a fuel leak in the valley. The drain is directly above the oil cooler lines. Or worse yet, when I pulled the IP off the old block I found one of the IP mounting studs was missing so oil was being blown out into the valley then running down and covering everything under the truck.

 

[bk95td]

Just some info on switching to syn. oil. Greg at lubrication specialist told me that amzoil makes a special cleaner that you add to your dino oil to clean inside of the engine before you switch to syn. The purpose is to not pollute the syn.oil with all the crud that the syn. will loosen up.
With the little bit of oil that you are leaking I wouldn't worry about it. You could make it worse taking it apart.

 

[iamdave0887]

Just some info on switching to syn. oil. Greg at lubrication specialist told me that amzoil makes a special cleaner that you add to your dino oil to clean inside of the engine before you switch to syn. The purpose is to not pollute the syn.oil with all the crud that the syn. will loosen up.
With the little bit of oil that you are leaking I wouldn't worry about it. You could make it worse taking it apart.

I'm good at making things worse. ):h

Anyways. I changed the oil and put on the Amsoil EoA24 oil filter. I didn't see any more leaks since last week. I"m not sure if its leaking from the rear main of its its just oil from my old valve cover leak that i didn't wipe away. the stuff looked shiny like oil, yet it was crusty and mixed with dirt at the same time when i went to wipe it all away, so its been there for a while.

I"m not really going to worry about it. Right now i've got to get a good look at my rear bumper in the daylight. Had a guy in a late 80s early 90s Honda accord with no headlights or driving lights on slide into my truck on a hill tonight(icy night) and take off. Cops are still looking for him. I hope the guys got a record and gets to meet "bubba" in prison. Sad part was the rear bumper wasn't in that bad of shape except for one dent that was there when i bought it from the scrapyard.