serious

i found oil all over the bottom of my engine and transmission of my new used car. here's the question. what can the oil tell me? the oil i found had a lot of crud in it. it was almost like oil mud. that would make me think that the oil has been down there a while and has collected a lot of road grime.

jonas

get your car on jack stands. clean as much of it as you can... brake clean works pretty well.. so does sure-shot.

let your car run for a while.. while its still on jack stands. re-check for leaks, and what type of oil is leaking.

BauleyCivic

Rear main seal and/or oil pan gasket are probably gone...

Spray the entire underside with brake cleaner then run it for a day...see if you can determine the source of the leak.

AutoXer

Castrol GTX super clean (or whatever it's called) works very well on oil as well, and I always use it to clean the engine. Definitely get rid of the crud, and put it up on jacks every day after cleaning to see if you can find the leak. I always try to keep my engine as clean as possible to make it easier to work on and determine leaks etc.