I fill like I'm being lied to. I just bought a 98 f-150 with a 5.4L 58.000 miles came with a warranty. the day after I picked it up I heard the motor making a noise. it sounds like a lifter I have had it back to the FORD dealer where I bought it 4 times now, twice they have kept it so they could try cold starts . now they have come back and said that the ford motor company has told them it is a Exhaust Resonance. They said Ford told them that this is ok and do not try to fix. has anyone ever heard of this?

 

No, I can't see exhaust resonance making a ticking noise. Maybe broken exhaust manifold studs, this is kind of a common thing, they let the manifold leak enough that it sounds like lifter noise and sometimes after the manifold heats and expands it seals back up. If they can't make it right, I would demand another truck.
Does the noise go away after it warms up? If so, it could be an exhaust leak or possibly piston slap. Either way, they should make it right for you.

EDIT Oh yeah, if it is a ticking sound, have them check the spark plugs to make sure that they are tight. They have been known to come loose and blow out. Then the head usually needs to be replaced. Just an idea.

 

Do you know of any way to contact ford them self to find out if there is any facts to this. I had two of there top tec's. say it sounds like it's somthing in the lower end, and I agree. I think it's time to contact prev. owner and find out if there was any info shared between them and dealer about the motor. do to comments made by the sales man I fill that old owner was given very little for trade. it wasnt due to miles or body.

 

You can go to ford.com. click on myford. enter your info, vin, etc and then you can contact them from there. I will be honest with you, they aren't a lot of help. I went round and round with them over a rough idle and they never mentioned the TSB about it. A member here helped me out and I got it taken care of. I also have a new dealer because my dealer(the largest one in the area) never mentioned it either.
If their tech's think that it is a bottom end noise, why won't they fix it??

I would definately contact the previous owner if possible.