I have a 97 Supercab 5.4l. Never had a vibration. Went to the dealer at 32k to have the warranty exhaust put on to move the outlet behind the rear wheel. Then the infamous 65mph vibration started. I now have 50k and the vibration is still exactly the same. Are there any TSB's out there to stop the exhaust from vibrating? The original exhaust outlet in front of the wheel had a big weight on it two inches from the end. It was ugly, but definately there to stop a vibration. The new exhaust has no counter weight. I haven't had time to try any hang a weight on the end. Has anybody tried it?

 

Not that I can't read - But I am trying to understand this "vibration." When I drive on the freeway approx 65 mph, my entire truck seems to bounce very rapidly. It's the strangest thing... it's quick, little bounces but I don't know if this is what everyone is calling the vibration. It doesn't happen during the entire trip on the freeway, just some parts of it. I do only notice it on the freeway, though, not city driving. I know my sister had an F150 with the same problem... her, now, Chevy does not bounce... any more details for me? Thanks

 

I just bought my 200 xlt 4.6l supercab 1 week ago. I too have noticed the vibration around 40-45 miles per hour and also around 62 miles per hour. I took it too the dealer and they think it's in the drive shaft. Looking at the posts i'm beginning to believe it's actually around the exhaust.
I love my truck but consisdering i have to get a new seal around the rear window and the hood repainted due to hydrolic fluid, this vibration just seems to be the straw that broke the camels back.
Any suggestions as to what i should do? My truck has 750 miles on it.