Larry, It seems to be engine/driveshaft speed related more than tire/wheel speed influenced. R Leo, your suggestion makes sense about since I think it does appear sometimes after the suspension goes into any kind of undulating movement but I don't think there is any transmission to body contact though. Maybe I'll just have to keep my speed topped out at 70 MPH. It seems to ride fairly smooth at that speed.
Thanks!

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DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012