spacers NOT new,
Precision LATHE machined=can't imagine any issues w/rotational balancing....but won't rule out.
..if take them out/drive it w/1 rear wheel & no more vibrations then hey....
both rear tires are balanced and bagged,
so dynamic bead balancing takes care of any additional rotational mass balancing EVEN in the brake drums I'd assume. was thinking to put on some clear tubing with fluid in it around tire during stationary jacked up tests and watch to see what happens.
will double check all alignments, toe, caster, camber,SIA.....etc. but they all seem correct.
and for me it's been a constant thing since before any RSK...spacers et. al.
IN FACT, I ONLY DID RSK ET. AL. to try and get her as smooth as I could and stop all vibes.
Camber on a Dana 60 kinda hard to get wrong if you've only replaced ball joints....?
Tie Rods et. al. just kept the same measurement across the gap... mine is always been near the shortest adjustment
but feathering outside of steer not a tie rod issue.
next steps when motivated....
rotate the steer to the back now with 4kmiles
run up to speed on blocks to see if can replicate stationary
run up to speed on dyno?
find a dynamic balancer in Southern California/Arizona?
OR........SHUTUP.....rotate the steer and keep on driving & hunting down Zombies...
can't feel the vibrations on the road when yer crushin' the walking dead!
Cupping/Feathering is NOT related/not a symptom of vibrations.
Desert Southwest =roads pitched intensely to handle flash flooding/cross dry washes
worse thing to have water pool-up on a road or hit a wash out that can happen in 5 minutes.
Long rear wheel drive/DRW vehicle;
Heavy Front End (4700lbs on front axle) always wants to go Downhill=mostly to the right
Pivoting on light rear end/rigid 4 tire pivot point (3500ish on rear axle)
so, i'm always holding pressure on the wheel to turn left.
did new steering box/shaft etc. and NO CHANGE.
it's just natural.
when the road suddenly shifts pitch, then I have to counter-steer the other way.
to me this explains the feathering/cupping on the outside steer,
although I'd expect it to NOT be equal on both tires,
but any steering at slow speeds grinds on outside edge.
here's some reading I found that's helping me a bit
Reading Tire Wear Patterns
ROAD CROWN ISSUES
Most highways are built higher at the center to *expedite drainage of rainwater and melting snow. This angled road surface, commonly called road crown, will cause a RWD vehicle aligned with equal side-to-side camber and caster angles to drift to the outer edge of the roadway. In contrast, most FWD and all-wheel-drive (AWD) *vehicles are not nearly as sensitive to differences or “splits” in side-to-side camber and caster angles because the driving thrust transmitted through the front wheels pulls the vehicle along the road crown.
Nevertheless, many alignment techs often “tweak” camber and caster angles on RWD vehicles to reduce steering pull on crowned roads. Keep in mind that camber angles in RWD vehicles tend to pull toward the most positive camber, while caster angles in RWD vehicles tend to pull toward the most negative caster angle.
If the front wheels have insufficient toe angle, the driver’s-side front tire will tend to wear on the *inside edge, since it’s trying to steer the vehicle *toward the center of the road. Conversely, if the front wheels have excessive toe angle, the right front or passenger-side front tire will tend to wear at the outer edge because it’s trying to steer the *vehicle toward the center of the road.
In summary, the diagnosis of any tire wear complaint requires a thorough interview with the customer concerning the history of the vehicle and any unusual driving conditions, including how the vehicle is routinely loaded. The diagnostic process also requires a thorough knowledge of how the fixed *angles, including steering axis inclination and Ackerman Effect, can affect tire wear. In most cases, *unusual tire wear patterns are the result of collision damage that can’t be detected unless the steering axis inclination and turning *radius or Ackerman Effect are accurately measured.
Reading Tire Wear Patterns - Tire Review Magazine
"But, it should be noted, the leading cause of outer edge wear on modern vehicles is over-enthusiastic cornering."
Not me, but for a heavy vehicle even mild cornering can be enthusiastic for tires?