Just curious of people's opinions.

Tony

 

Does anyone know what percentage of 03s have piston slap? And why would adding an extra valve do anything to make piston slap go away. My guess is they will tick like a clock and rattle like a diesel. Just my opinion.

 

now 03 why do you think they will tick and rattle with an extra valve?

there are millions of multi valve engines out there with 3,4, and even 5 valve per cylinder and they don't tick and rattle.

 

the piston skirt is longer on the 04

 

All I am saying is that an extra valve is not going to solve the problem of a piston slapping engine. Who knows though, maybe the longer piston skirts will help.

 

I think Ford will probably have the piston slap taken care of for the most part, but it may rear it's ugly head. Let's hope not. As for the bet, I bet it's gone, but I don't want to bet a lot on that.

 

Has anyone offered a technical reason for the piston slap problem yet?

 

The longer 'skirts' are there to eliminate the slap. We shall see. I am a bit doubtful. I hope its not replaced by something worse!

 

I no longer have any fear of piston slap. It IS very annoying on a new expensive truck.

This year I started a business that does fleet maintenance. Several of my customers run fleets of Ford Triton engnies. Lost of slap. I asked each one about it. Not one failure from it. Dozens of engines, nearly every one slaps cold, and not one failure. The mileages on these things can exceed 250,000 miles.

So anyway, back to the question at hand. My vote is that there will still be slap. My guess is that if the piston skirt is longer it will help, but some engines produced will still exhibit the noise.

 

My question would be this. How can there not be damage to an engine that has a piston rattling around in it like that? You may want to check out pistonslap.com. There are plenty of pictures there that will give you reason to be concerned.

 

probably not much damage due to not as much play as one might think. (just a hunch as i too have seen 5.4 work trucks wich have been through it all and still keep going, the only fleet engines that seem to go out is the ones that never get an oil change or have been run low on oil, smashed oil pans etc, you would also be suprised of how much dirt they eat (cheap air filters) and still keep going)

Ford did change the pistons on the 2v 5.4 with an offset pistion pin which was to help with side thrust on the pistion (as the rod comes up there is side thrust on the pistion and the same on the way down)(minor and major thrust angles 90 deg to pin)

Why piston slap when cold? (my opinion)pistions are cam ground and once at operating temp become fully round - hence noise goes away - if noise did not go away at operating temp then piston would be collapsed (skirt has no taper or is tapered in), why the 5.4? such a long stroke and pistions with a short skirt.(longers skirt is on the minor and major thrust angles of the piston, so one would think the 04 f150 should not have piston slap)

Also an engine builder told me that a cold engine should never be reved over 3,000 rpm as that can lead to a collapsed piston (skirt) as the piston is oval (cam ground) until it reaches normal temperature.

This all seems to make sense to me but as I said this is just my opinion