My 1999 4runner has a check valve attached to the driver's wheel well under the hood. Mine is leaking what looks like oil. It is connected to a rubber line that runs under the engine.

Anybody know anything about this condition?

Thanks

 

does it have a silver cap on it and does the oil smell like gear oil...if so sounds like the front diff breather I have heard there are suppose to be 2 of them one for the TC and the other for the front diff but I can only find one on mine

Anyway having oil shooting out of it is a bad thing from what i have read it usually means the front diff could be overfilled and or a pluged diff breather.

 

It does look similar to the rear diff breather valve. Kind of strange though, I changed the front diff oil several years ago and it has just started leaking.