Diagnose my oil leak

Here's the pictures i took just now. It leaves a spot about the size of a quarter overnight if i drive it. If i dont drive it, it doesnt seem to leak. Its not the valve cover, i checked that, theres not any oil, pretty clean for the most part with a little sludge from spills from oil changes. All the valve cover bolts are tight. It seems to only be only soaking the passenger side half of my bellhousing too. Another thing thats weird is it all of a sudden got worse when i changed my oil even though i went to a thicker oil AND added a quart of lucas. any thoughts are appreciated.

My guess: Oil filter mount O-rings?

Good luck. YMMV.

Rear main, oil filter adapter O-ring, and probably your valve cover. All very common oil leaks on a 4.0 Liter

Mine was leaking from the front timing chain cover, several of the bolts behind the harmonic balancer had backed out. Took a water pump replacment for me to see it and tighten them back up. I always wondered where that quart used to go between oil changes. I just checked my dipstick yesterday and it is exactly where it was when I changed it. I have the splash guard still in place so looking up from ground is not possible which is why it took the WP problem to spot it.

can't see much from those pics but i'm gonna guess its either the rear main leaking (very common after age) or valve cover, i know you said you checked it but the tend to leak from the very back of the cover alot where you can't see it and it'll drip down and make a mess all over the place like you have. you best bet is to clean everything up real nice then drive it for a day or so and check it to see where the leak is starting, should be easier to find once its all cleaned up nice.

eric

well whats weird is. it never leaked more than rop every week or so. now it leaves a quarter size drop overnight. it seems like it got worse immediately after i changed my oil about 1000 miles ago. it had 10-30 non synthetic in it. i replaced it with 5 quarts of non synthetic 20w-50 and a quart of lucas oil stabilizer hoping to plug up the tiny leak it had. could the thicker oil have somehow caused this to worsen??

by the way, i just went out and drained 1/2 quart of the oil and replaced it with 1/2 quart of "NO LEAK" oil additive. its the most expensive stuff we carry at autozone and the used car dealers usually buy all of it we have every time our truck rolls in. anyway, after only 1000 miles, my oil is very dark brown already. i dont get it. is the lucas cleaning all the sludge out of my motor exposing these leaks or somethin???

stop using all those additives and garbage, especially if they are'nt changing anything. until you fix your leak just check your oil periodically.

eric