I like my truck but sometimes wish I had the 5.4. However the posts about piston slap and blown plugs make me wonder about the 5.4. Are there any particular model years that are especially bad about those problems?

 

My '03 has a 5.4L with 35k miles. No problems here. I change my oil every 5k per the scheduled maintenance guide using Motorcraft 5W-20 as called for. It still runs like new, but that doesn't mean I'll never have that problem. Others will reply to your post, so keep checking back here.

 

Thankfully, NOT MINE

I have a 1997 with 115K miles on it. Other than a timing-cover & valve-cover gasket, I've had zero problems with this truck in general. And no piston slap.

 

Its really a crap shoot...Piston Slap is not harmful to the engine (at least in the span of time most people use them), and the blown plugs are not as common as you would think.

Mine has piston slap, but only on cold mornings, and mine isnt all that loud. It goes away within like 30 seconds or so anyway.