I feel like I’m taking crazy pills, but hear me out: I have Vossen 21x10.5 wheels on my car. I’ve been seeking the perfect stance. Therefore, I recently got an alignment and set my rear camber identical on both sides. Here’s the weird thing: with the camber angle is exactly -1.24 on both sides, so both sides *should* be identical. But the top of my right rear wheel sits about 3-5mm farther in than the left rear wheel. nothing is wrong with my suspension, all bushings and whatnot are in good shape....I can’t explain this one. Can someone else with flush fitting wheels check me on this??
Even though I’m religious about tire pressures, my right rear always wears faster on the inside than the left, ie a tiny more negative camber? That little difference *could* answer your question, but 3mm diff could also be in the noise/measurement accuracy since I assume you used a couple diff straight edges or rulers here.
I don’t know about the model s, but most car have front and rear subframes. It’s possible the subframe is shifted. I had an Audi and had this exact issue after fitting coilovers and spacers and the subframe was the issue.
Do you have aftermarket camber arms? The stock camber is not adjustable. Also, are your ride heights the same at both corners?
that’s interesting, I hadn’t thought of that. Subframe shift seems like a big issue, no? Especially 3-5mm...
My 3 is the same way. A 5mm difference left to right means the subframe is only shifted 2.5mm to the body. Not much really. Not noticeable at factory height and offset.
i wonder if the wheels were at different levels of droop at the time the alignment was made. Do you have an angle finder that you could line up against a straight edge against the wheel faces? That would let you see the actual degrees of camber with the car at rest.
Keep in mind that you have not just the subframe but you have the body, the tire, the wheel, the rotor you even have contamination between the wheel and rotor, Etc. This all adds to the stack up on the tolerances. So for the whole system to be out 3 to 5 mm maybe within tolerance. I don't know if that's truly happening but that's one thing to consider.
Pull the wheels off and measure from the rotors to the fenders. That would tell you if it is a camber measurement or an off centre rear end (wrt the fenders at least.)
Funny you should mention this, I haven't lowered my car yet and just eye balling it, the right rear wheel look like it has more negative camber than the left side.
I was told by Tesla, the right rear wheel will always wear faster than the left bc it is considered the "power" wheel. But i though my car was AWD..??
I had a nearby shop just check (not adjust) my alignment, and they showed -1.15 on the left, and -1.25 on the right. So, could just be a slight difference in the machines' calibration. I adjusted my camber on the right wheel to get it visually the sale as the driver's side, and will have the toe re-adjusted this week. We'll see if that fixes it.
I'd imagine it's like torque steer on a FWD car - unless your half shafts are exactly the same length, the shorter one is going to get more power. So, in this case perhaps that's the right side.
They are AWD but they have open differentials on the front and rear so the wheel with less traction on each end of the car i.e. less weight on it will spin.