Have a '94 850 with a leaking rear main seal - if at all possible, I'd prefer not to have to pay to fix it right now. I'm going to try switching to high-mileage oil, and if that doesn't work will try one of the sealant additives like Bar's. I just want to make sure that I can get away with this for now - obviously the seal will have to be replaced sometime, but can I drive it like this for a few months? Until the fall (assuming I keep an eye on the oil level and top off as needed)? Also, is the seal likely to fail catastrophically at some point?

Thanks!

 

I lived with it for a year. Watch your oil level and try to park in the same spot all the time. The only thing you risk is rubber failure over time. The oil will travel to the rear of the car as you drive. It will coat everything inluding your rear bumper or hatch. Everything rubber will get coated, causing it to swell and get soft. Nothing will happen but it will be a big mess over time. I am so glad I changed out the engine and got rid of the leak. I couldnt park an anyones home I knew because of the mess I left behind. I still have the spot where I parked everyday, it probably wont go away. I have even pressure washed it. From the picture...guess where I parked.

 

I lived with a leaking main for months and finally fixed it when I got sick of sitting in the smell of burning oil at every stop light.

FYI - My rear main went from a slow leak to loosing a quart of oil every 100 miles after changing my PCV system (it seems once the pressure went down in the block the seal collapsed).

 

I lived with one for over a year and never had an issue. You need to check the oil every few days and top it up as needed. I left a 5 quart bottle of oil in my trunk so that I would always have it with me.

 

Mine has been leaking for years. Started out as a small leak that later turn into a big one. I use the 10 w30 oil. I prefer you not to use the sealant additives, for last time my dad put it in my car it made it worst. About every 200 miles I lose 1/2 qt. and at high speeds and long distances oil would cover all over the left underside of the car, exhaust pipes, bumper, and rear wheel well and wheel. Big mess. Just rinse it after a big trip, for it seems to (melt?)softens the undercoating like Boxpin said about the plastics. Short trips around town for instance I tie a rag on a stick and try to wipe the oil droplets where it's leaking at the end of the day. Often helps from spreading all over and have to wash the underside as much for me. Also if can don't take long distance travels. After a 400 mile trip it cause mine to leak very bad.

P.S. Does that mean I have to change the PCV every 10 yrs or so? I have yet to change it.

 

Update: Talked to the mechanic and apparently the majority of the leak is from the cam sensor (which I assume is where the cam seal is?). He quoted $307 for the part, but I found what I think is correct here: http://www.fcpgroton.com/product-exe...ategory_id/116

Is this the right part? Does the sensor itself really need to be replaced because of an oil leak, or is it possible to simply replace the seals?

 

My suggestion is to try Valvoline MaxLife 10w40...it did wonders for my rear main seal. Although, other people report no improvement.