Rear Main Oil Leak? - 98 Expedition

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I am having an oil leak on my 98 Expedition. It is gradual and cannot see where the leaking origination source is.
The oil is mostly accumulating on the bottom of the bell housing up to the rubber insert for the torque converter drain bolt access, some at the bottom of the pan drain bolt, on vertical surface of the rear face of the oil pan and the bottom of the rear 2 pan bolt heads. I am not sure if it would be the pan gasket or the rear main seal. If the rear main seal, is that an expensive project?
 
Never seen a easy rear main. Try a product like LiquiMoly Motor Oil Saver for 2 OCI 's. If the results aren't positive or to your liking then you have a project on your hands.
 
If it is the rear main seal, the transmission has to be removed for it to be repaired. It could possibly be the back of the oil pan. But without seeing it if I had to bet money it's the rear main. The part itself is cheap, but it's obviously labor intensive. I'm guessing if you paid a shop you're looking at 600-1000 bucks.
 
My Rear Main Seal has bee leaking for a couple years.
I have been using High Mileage Oil hoping it slows it.

Other than that, I stuff some Paper Towels between the engine and transmission.
 
You could try a HiMi oil or use something like Bars Leaks for Main Seals. Remember seal conditioners don't work overnight, it can take several hundred miles to see results. And they do make a UV dye that you put into the crankcase and run it for a while then you use a blacklight and glasses to look for the oil leak route, tracing it back to the source.. obviously fixing a rear main can be expensive so hopefully a seal conditioner can help but there's a chance that that train has already left the station and you're just on borrowed time before that seal finally go's.

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It's a small leak for now, I think an additive might make the most sense to try to get it early. Anyone have any experience with oil pan and rear main seal stop leak additives? Any concerns about how an additive would compromise oil or internal lubrication. I wouldn't want to try to fix one problem and cause another.
Maybe a heavier weight oil, like 5w 40?
 
Originally Posted by Fitz98
It's a small leak for now, I think an additive might make the most sense to try to get it early. Anyone have any experience with oil pan and rear main seal stop leak additives? Any concerns about how an additive would compromise oil or internal lubrication. I wouldn't want to try to fix one problem and cause another.
Maybe a heavier weight oil, like 5w 40?

A rear main leak isn't necessarily a death sentence. It could last like that for many more years..or it could fail completely tomorrow, you just never know.

Give the HiMi time to work...but in the past I've used Bar's Leaks with varied success. An additive isn't going to grenade the engine or oil, and i *think* they're mostly ester???.. Again, much depends on the seals condition right now as to whether or not a stop leak is gonna be able to make a difference but if it does go while you're driving it's almost certainly buh bye to the engine..so it's worth trying something right?

Also, the people at Bar's/Rislone (same company) are very helpful, over the years I've called upon them maybe a half dozen times and always pleased with their customer service and they always answer the phone with a live person. They can help you identify which product will work for your make/model/year/size of leak etc. Believe it or not there are different types of seals. I would recommend taking 5mins and giving them a call.
 
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Thanks, I have been running M1 high mileage for years, just switched to high mileage extended performance on last oil change. It may be a coincidence, but this leak started around the same time I discovered a small coolant leak, which dripped down from a hose connection on the top of the motor down to the same area where the oil leak seems to be coming from. Originally, I thought the coolant was just washing residual oil from the outside of the motor and it was accumulating at the low point. Then I was thinking that perhaps the coolant affected the pan seal. Not sure if it could be relevant or not.
 
Someone "snugged" the oil pan bolts on my car. They broke 8 of the 24 bolts, and made me pretty miserable when I changed the pan gasket.

My rear main spun in its bore a year later. Massive leak - had to add a gallon and a half coming back form Chicago.
 
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