Jeez I really feel like I'm steppin’ on Bill's toes here or stealing his thread, but we are experiencing the exact same phenomenon so that’s the only reason I’m bringing up my symptoms also. In my case, last year when I started going through the mechanical work on the driveline I actually started at the front. New front motor mount, two new rear motor mounts, all new u-joints, bushings, center support bearing and rubber. Originally bought the new Power King bias plies, and balanced them at three different tire shops. I swapped them front to back; I rotated the wheel on the hub one lug at a time to see if that made a difference. In desperation I caved in and put a new set of wheels and Cooper tubeless radials on to no avail. All new front wheel bearings, properly adjusted according to specs. New bearings in the rear full floating hubs properly adjusted according to specs. I inspected the rear axles while they were out and they were like new, and everything went back together just as it should with no binding or forcing. And once again, new gas shocks all around. I can’t think of anything more to I can replace other than the truck itself.
Trying to describe a feeling is like trying to describe a color; ya just gotta see it to fully appreciate it. This oscillation, vibration, hopping, tailgate bobbing, throbbing or whatever label one chooses for it is still there. I’ve been pulling what little hair I have left out over this one for a year now. It really makes for an annoying ride as it comes in right around the cruising speed, that being limited to about 45mph in my case.
The thing that shoots my theory of the frame flexing down is that Bill describes the exact same problem with his 1/2 ton as I’m having with my 3/4 ton, two very different frames. And apparently no one else in the world has this sort of a problem with his or her Advance Design truck.
So Bill I really can understand your frustration.
Denny Graham
Sandwich, IL
