Hello!

As some of you know, I have a lumber rack on my truck. Somehow, the aerodynamics of the front bar, coupled with the cab lights, makes the roof vibrate. At freeway speeds, this vibration gets bad enough that I'm getting a humming in the cab that drowns out the engine.

I know that the rack's doing this simply 'cause the vibration/noise disappeared when I had the rack off to paint it. I currently have the headliner out (needs to be re-covered), so I'm looking right at the bare painted metal of the roof. Before re-covering and re-installing the headliner, I'd like to get some insulation on the roof. Is there a good material out there that's designed to minimize vibration? IIRC, Dyna-Mat's designed to do that for speakers, but I could be wrong there.

Any thoughts would be appreciated...and, on top of the vibration reducing stuff, I'd like to put some noise/heat insulation in.

Thanks in advance!

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2001 VW Jetta TDI, 5 speed, daily driver
1991 Ford F-350, work in progress
1984 Ford F-250 4x4, 6.9l turbo diesel, 5 speed manual
Previous oilburners: 1980 IH Scout, 1984 E-350, 1985 M-B 300D, 1979 M-B 300SD, 1983 M-B 300D
Spark-free since 1999