Hey guys,

Quick question. Changed the oil on my 4.6 w/140k now, I went with synthetic, I've noticed alot of noise on start up( maybe piston slap or some thing). I don't remeber this amount of noise with non-synthetic oil. I am contemplating going back to non -synthetic. Will I have any problems switching back?

Mike

 

Nope. You might give the high mileage oils a try.

Although I plan on just sticking with the Motorcraft 5w20 for my engine as long as I have the truck.

 

same here

 

Ditto.

 

My 99 did the same thing when I switched over. What kind of oil filter are you using? When I changed to a motorcraft filter with the anti-drainback valve from Fram the noise went away. This might help

 

Have to check on that filter. Screwed up my hand at the time of the oil change and ended up bring it to a local service station. I said I wanted synthetic oil, but did not preference what type of filter I wanted.