Hey guys i have a 99 lightning with 56k on the OD and about 30 of them with my 4 lb. At jdm day ( i know it was quite a few months ago) i ran it and for the first time i opened the hood and saw Smoke. I was scared sh*tless and i looked under the truck and a couple drips of oil were hitting the cat and smoking neddless to say i ran my best time of 12.7 in three runs but many people told me that all 5.4 leak. It just so happens that it has to land on the cat and scare the sh*t out of me like i blew my motor or something. Anyway i always use mobile 1 synthetic and i always put about half the bottle of lukas oil stabalizer in it. At jdm day i just changed my oil the day before and didn't put any lukas in. Since then i had no leak that i noticed. But does anyone else have this same problems or what? I'm guessing the stabilizer works but what do you guys use. Obviously plain oil doesn't stop the leak.........and yes the leak came from the passengers side.

 

head gasket. mine crapped out, 100% stock @ 31k on the clock. so thats my guess. got it fixed under warrenty and modded it as so as it was done.

Chris

 

After a night of racing,I notice 2 little drops of oil on my garage floor.I guess it was sweating HP....

 

It is a head gasket. Mine is leaking from the notorius right rear corner and driping on to the cat. Well only on nitrous runs. Boost only runs is not enough to make mine leak. I could just pull the head and have it resurfaced and put on a new head gasket, but Im just going drop in a built motor as I want to push it a bit harder now! From what I understand this was a common problem with the 5.4's. Ive also heard that the head gasket that Ford uses now are better, or "revised". Get that head off of there resurfaced with a new head gasket and hit the track!

 

yep mine did it to
i was in the process of modding mine when i found it. pass side head at the rear 2 inches. mine was also done under warrenty

 

I haven't seen that one, but I got the OTHER 'famous oil leak'.

Gaskets looked fine when I tore mine down at 38K miles.

Herb

 

My old engine had 34K miles on it and never leaked. The new engine has about 1500 miles on it and doesn't leak.