Ok, I have a 1998 F-150 with 4.6. And I have this annoying racket that comes and goes. It sound like a someone pulling an empty soda can with a string. I have yet to get up under my truck because it just started. I don't know if it is exhaust related or somthing loose under there. But like I said, it comes and goes. Can anyone help me .

 

Sounds like it could be an exhaust hanger or something else rubbing metal against metal. Next chance you get crawl under there or put it on a lift and shake your exhaust and other various components and see if anything is loose. Then just take it from there

 

Does it sound like this?



If so, sorry its not exhaust, its your rotor shields on the rear, those plate looking shields that you see when you crawl under & look at the wheels, I need to get mine replaced.

 

I will get under there as soon as all this snow melts that we got last night. Also when the racket starts, I can put the truck in neutral and rev the engine and I still hear it that soda can sound. Thats why I say it may be exhaust related. But Im going to check my brake shields and all just to be safe. Could it be the cats or the muffler?

 

Might be a rattling exhaust heat shield...

 

also tap the cats with a rubber mallet ,piece could have busted off inside.

 

X2 thats what my guess would be I had it happen to me on my Z71 the inside of the cats were falling apart and the peices inside were rattling.

 

Well I found out what the problem was. It was one of the cats. The right cat had fallen apart inside and made my truck sound like I was hauling soda cans. I lucked out and got it replace for free. I also put own my own ehxaust out in my yard. I got a Cherrybomb exhaust system and my truck sounds awesome. It has a nice heavy cam at idle and a beast roar when I hit the gas. Thanks for all your help guys.