I've been chasing a bad vibration/tire hop in the rear. Put tires on it mid-January. Fronts look brand new, rears are smooth.

Think this could be the cause, or most of it?

RR Lower Dogbone mounting hole

Could it be because of:

http://www.youtube.com/watch?v=FAx7lDNmcmQ


Seriously, I've never seen what you posted. How bad is the vibration? I would think if it was the dogbone mounting hole, it would shake like crazy.

Need more info. Vibration and tire hop are really 2 different things.
Vib - when, what speed, under acceleration, deceletation?

Tire hop, again when? Hard launch, around corners?

The only thing in your vid that I can think of that would cause that is a bolt that wasn't tightened properly. It had to be working on the holes for a while to do that.

Real bad.....

Top hole is similar. The sleeve in the bushing the bolt passes through has a similar elongation, more so on the bottom bushing than the top.

Vibration increases with road speed. What I think the "vibration" is - maybe my description isn't very good and may be misleading - is the tire either shaking back and forth or hopping up and down like a basketball.

chicken vs egg, which came 1st?

fortunately those brackets unbolt, good time to upgrade to DRM brackets if you want to.

how the rest of it look, u-joints etc?

If you can see it hopping like a basketball, how old are the shocks?

When I got the car, this is what happened to the RR outer u-joint...

RR Outer U-joint

I suspect that's when a lot of the problems began.

I can't see the tire hopping - I'll try to get someone to follow me or drive beside me and look at it. I sure does feel like the tire is moving a lot. The wear pattern was feathered across the center tread blocks.

U-joints are new, within the past year, both outer tie rod ends with in the last two months.

Shocks passes a basic push test and show no signs of leakage. I know, not real accurate or scientific, but the shock doesn't feel especially worn. I'd think if the shock was bad enough to be the sole cause, it would be noticeable with a basic push test. Rebound adjuster - Koni single - still functions in that I can see a change in extension when I fiddle with the knob.

Have you checked the rear wheel bearing for play, should be done with the caliper off and a dial indicator but, if there's any movement in and out it ay be bad.

Have you checked the wheels for runout, lateral & radial?
This can be done with a pointer C clamped to a jackstand, check at the edge of the rim and on the bead edge (for up & down).
Or, if the car's drivable, switch tires side to side.

Bad shocks will amplify the problem but probably not cause it.

Sorry, rear hubs are two weeks old. This is the second wheel/tire combo this has happened to. These tires were mounted up on these wheels when I changed the tie rod ends. I was hoping the new tie rods ends had cured the problem.

I do notice a difference with the tie rods and hubs.

I think just about every part in the rear is going to be replaced before all is said and done. Each part replaced makes a difference - new tie rods, car stopped wandering on accel/decel, new hubs, roughness and noise went away. I know it needs a new pinion yoke - I have one sitting in the garage from Randy's R&P.

Sorry if I'm omitting a lot of details - been frustrated for a while with this. Thanks for the help and suggestions thus far...much appreciated.....