Engine/Transmission (1998.5 - 2002) Strange noise

[Warpig]

Since day 1 my 2002 has been making a strange noise. It only happens at 70-75 mph. It sounds like a scrubbing sound and will stop when I take my foot off the accelerator pedal. As soon as I accelerate and maintain 70-75 mph the noise starts again. This noise has nothing to do with engine rpm, as I have tried it with od off at the same rpm. Along with the noise I can feel a slight vibration at my feet, but I can't pinpoint it. I spoke to the dealer and he told me that since it happens at 70-75 mph. he can't test drive and diagnose it. I have been told by some that it could be an exhaust drone. I suspect that it may be a unbalanced driveshaft or bad angle. The noise isn't that loud, but sometimes will drive me nuts because I know it's there. Any thoughts??????



Tim W.

 

[mberry]

Sounds like mine, although mine does it at almost any speed. I can feel the vibration in the pedal and hear it at slow speeds. Wish I knew what it was. I sympathize with you.

 

[RonaldLarson]

Me thinks...

they all do it. It is probably the grunting sound that eminates from the Cummins when it is pressed to perform. In my experience, I am sure the sound is partly the sound of air rushing past the air filter. Remove your air box snorkel, and it will get louder. I love the sound, and the feel of the thing pulling for all the world!

Ron

 

[Mundgyver]

Just a W. A. G. here, but have you looked at the piece of rubber that seems to cover the lower part of the radiator from the bumper back. It's fixed to the bumber but can flap. I'm not sure what it's for. When I put my front hitch on with my 1/4 inch armor plate I tore the thing out. That might make a little noise if it was flapping up and down in the wind. Just a W. A. G.

 

[Warpig]

Definitely not the rubber flap. This noise / vibration only happens between 70-75 mph. Over 75 mph and it goes away completely. Coasting at 70 - 75 mph no noise. I used to have a Jeep Wrangler and if I went too fast in 4wd I'd here a similar noise except much louder, and then it would get worse with increased speed. I have 7000 miles now and it has not gotten any better or worse.



Tim W.