best oil?

[funair02]

i use mobil1 10w30 in my mach1 and lightning also a ford motorcraft filter. no problems here.

I had a lash adjuster fail using, I believe 10-30 oil. I can't confirm, but after fixing them, I played with the hole that fills the adjusters. It is very small and 10w had problems entering it...
Just FYI

 

[4a7191a]

probley wasnt the oil, ive seen a ford 5.4L in a fx4 with 348k miles with mobil1 useage. its dead now, but wow to that for sure.