Probably ignorant question - Page 6

2wdMuddin · #76 07-13-2014, 09:36 AM

Quote:

Originally Posted by kmcloonan

I am the original poster for this thread - So fast forward 2+ Years.... I was under my truck last weekend fixing an exhaust flange leak - the rusted flange was right next to the weight that is the subject of this whole thread. It's a good thing I was fixing the flange, because I noticed that the "U" bolt that held the weight to the exhaust pipe had 99% rusted through, and was just about to fall off. I would not want to be the guy driving behind me when it did fall off....

So I gave it a sharp tug and it came off. I set the weight aside and went about fixing the rusted exhaust flange. Later that day I went for a drive, and the truck was much quieter since I fixed the exhaust leak. But when I got up to about 60MPH, I noticed a pretty strong vibration/deep hum that I never had before. It went away when I slowed down or sped up, but right around 60mph it really was noticeable.

I came back home, got a new "U" bolt clamp, and rehung the counterweight on the exhaust pipe. Went back out for a drive, and no more vibration at 60mph, or any other speed. So now the mystery of the goofy weight on my exhaust has been solved once and for all.

oh jeez im surprised to see this thread back up lol

GLH · #77 07-13-2014, 04:56 PM

Probably some type of viscous fluid inside, like some motor mounts have.

kmcloonan · #78 07-14-2014, 06:25 AM

Well, since I was kinda certain I needed the weight back on the exhaust, I was reluctant to cut it open to see what was in it.

I can tell you that I tapped on it a bit, and it feels like a can full of concrete. Very solid and heavy.

outlaw99 · #79 07-19-2014, 08:12 AM

I'm new here...only been a mamber for a week or so and stuill catching up on posts, but I could have told you at the beginning it was a vibration damper. I drive school busses and all of them have the same thing. I've even seen motorcycles with them, but I doubt they are really needed there since the exshaust is so short. Like the Tacoma Narrows Bridge, the vibration is dependant on the diameter of the exhaust pipe versus its length. Soewm of the newer busses with large bore pipes don't have them, but all of the older ones with the smaller bore pipes do.