Ive come to the conclusion that my dads 1999 F-150 has piston slap, car has 55K on the clock, is there anything that can be done? is this something to really worry about? Ive heard of cars having this when installing forged aluminum pistons. Its just dissappointing to hear about this.

Storm

 

Most of what I have read here on F150 says the noise goes away with synthethic oil and a good oil filter... click on the search button and search the forums for "Piston Slap" and you'll see there are tons of posts about it...