Mystery oil leak near passenger wheel

[priest05]

I was changing my drive belts on my 03’ Pathfinder LE and i came across a build-up of oil and dirt in the back of my skip plate. I think this is because of the old O rings but i’m not 100 percent. Any ideas/ suggestions on what it could be?

[Mike W.]

A leak by the pass side wheel is likely the oil cooler. There's a couple of O rings in there, I only replaced the big one and it fixed the leak. Seems to be a common problem. I didn't even remove the coolant lines, I just cleaned it up so no grit would get in and pulled it off far enough to get to the O ring. Easy job.