It's about time for an oil change on my 91. I got 102k on the clock and have been running the stuff the ford dealer puts in since 97k. So i'm wondering if I should keep using whatever ford uses or if I should get something else. My car doesn't appear to be burning any oil either. And before I get flamed I go to ford because my family works there and its easy. any knowledge is appreciated!

 

Do you know what weight they are using. I read an article that said a 20 weight was great for the 5.0 because of the spacing in the lower block that these engines created alot of heat. The article went on to say that after a 100k tear down and using the 20w that the main bearings still looked brand new. I definitely wouldn't go with anything under a 10w-40

 

10w-30 penzoil here for over a year no problems, great compression, great oil pressure, great ride.

 

I just found out that they use 5w30 semi-synthetic.

 

Irish50, 20 weight is pretty heavy. Maybe the bearings looked ok, but it puts stress on other things because of the oil pump having to work harder. 10W-30 is a good for these cars.

 

My stock portfolio would appreciate your castrol purchase.

 

Haha, go Mobil 1.