Negative Camber in the Rear and Expensive Tires

[lolachampcar]

R2B,
Normally I'd write a detailed response but you really need to look through this whole thread and [lolachampcar] Performance Upgrade Efforts to start. You will have a much better understanding of negative camber in MS, why it is there, why coil cars are different than air cars and perhaps what can be done about it.

 

[R²B]

R2B,
Normally I'd write a detailed response but you really need to look through this whole thread and [lolachampcar] Performance Upgrade Efforts to start. You will have a much better understanding of negative camber in MS, why it is there, why coil cars are different than air cars and perhaps what can be done about it.

Will do, thanks.

 

[lolachampcar]

To summarize


FMVSS-126 mandates electronic stability control
The only way to pass the emergency wheel yank (see around pg 15) is to use rear negative camber so that the car "rolls" onto more lateral contact patch when the back end is loaded. This is why MB, Audi, BMW,,,, are all using negative camber.
Tesla got the coil spring MS to pass.
The air cars have higher negative camber as they ride lower. Tesla chose not to have a different set of suspension for the air cars to correct the higher negative camber (due to camber gain).

Air cars have a lot of negative camber. Over time, you will wear the inside shoulder because this is where you are putting all the car's weight. It is most pronounced at first then tapers off as the inside wears down and the rest of the tire starts to pick up more load.

Too much toe massively accelerates this wear tendency.

 

[Lloyd]

14 K Miles

 

[thimo]

14 K MilesView attachment 58834

To me it looks like an alignment issue with too much toe. If it's just camber I would expect the whole worn surface to look something like this:

 

[Lloyd]

Tesla checked Alignment and states "OK" both before and after annual service.

 

[yobigd20]

Tesla checked Alignment and states "OK" both before and after annual service.

IMO they either don't know how to do alignment's correctly or their machines are programmed wrong. Or they don't check alignment at all and just write 'OK' on your service. And before anyone says 'Tesla would never do this', I personally caught them lying and called them out on it right on the spot. Not for alignment, but instead for making up numbers on my tread depth. During one of my service visits, I measured every tread on every tire and knew they were all ~6/32" right before I dropped it off that morning. After service was completed and they said my service was done and I was picking it up and they were going over all the line items, all 4 tires were written down as 9/32" tread depth. I called BS right on the spot and said there's no way those treads were actually measured and that those numbers were made up since I checked them that morning. The manager went out and rechecked all of them on the spot and came back and corrected the paperwork matching my measurements without saying a peep. He knew his tech lied and there was no if, and's, or but's about it. So based on that experience, I would not be surprised if some service centers don't actually check alignment and just write "OK" on your report.

 

[Merrill]

You definitely need to ask for a print out of before and after. I asked that and saw that the alignment was out and it showed the corrections made, I supposed they could of made that up as well. But definitely showing less wear than before.

 

[lolachampcar]

If you suspect issues with toe, toe bars are cheap and very easy to use.

 

[Lloyd]

You definitely need to ask for a print out of before and after. I asked that and saw that the alignment was out and it showed the corrections made, I supposed they could of made that up as well. But definitely showing less wear than before.

I asked for a printout after it was done so I could check their measurements. I was told that a printout was not available.

 

[zwede]

I asked for a printout after it was done so I could check their measurements. I was told that a printout was not available.

I asked for and received before and after printouts from the Dallas SC. Unfortunately my measurements didn't match the after printout. I suspect the machine was out of calibration.

 

[Lloyd]

Mine was done on a brand new machine which was just installed at the Van Nuys SC. I believe mine was the first car. I'll see how my new set wears.

 

[thimo]

Mine was done on a brand new machine which was just installed at the Van Nuys SC. I believe mine was the first car. I'll see how my new set wears.

If it's a toe issue, check early and check often. I once ran through a set of front tires in around 500 kilometers.

 

[artsci]

I just spent about two hours reading through most of this thread. I want to express my gratitude to lolachampcar for starting the thread and sharing his experience and expertise through so many detailed posts. You've given all of us knowledge that many of us will find invaluable. This is one of the very best examples of how the TMC community pools the expertise of its members for the benefit of all Tesla owners. When they're available I'm going to acquire the adjustable links my friend SUPRKAR has worked to have made and set the rear alignment to what lolachampcar has recommended (I got far too few miles out of my first set of tires).

 

[Luis Mengual]

I just spent about two hours reading through most of this thread. I want to express my gratitude to lolachampcar for starting the thread and sharing his experience and expertise through so many detailed posts. You've given all of us knowledge that many of us will find invaluable. This is one of the very best examples of how the TMC community pools the expertise of its members for the benefit of all Tesla owners. When they're available I'm going to acquire the adjustable links my friend SUPRKAR has worked to have made and set the rear alignment to what lolachampcar has recommended (I got far too few miles out of my first set of tires).

Completely agree Artsci, I read most of this thread as well, and from my pro experience it´s very interesting lets training other people, helping to understand how suspension works and its particularities.

Let me add that could be a great improvement to develop these adjustable camber links or even a upgraded suspension kit to strenghthen this "speakable" area and ask to Tesla R&D team to create a bulletin with a setup more friendly to the rear tyres untill this kit appears. I think all major modifications needs to be tested, approved and documented by Tesla giving the best sollution asap.

 

[linkster]

Let me add that could be a great improvement to develop these adjustable camber links or even a upgraded suspension kit to strenghthen this "speakable" area

Although not adjustable, Chris1howell's high-strength I beam .210" stretched UL's are currently available that will reduce rear negative camber approx 1 degree.

Rear Upper Suspension Link for Tesla Model S OpenEV Store


I do like the idea of adjustable UL's coming online soon from BBC Machine to eliminate L to R spread and to give members a choice between these two aftermarket solutions.

 

[Sans Gas]

My rear tires failed (belts through rubber) after 13K miles. I was told you should have rotated them at 6K miles. Ya think? Here is the recommended tire rotation provided by the Highland Park Service Center.

 

[jerry33]

My rear tires failed (belts through rubber) after 13K miles. I was told you should have rotated them at 6K miles. Ya think? Here is the recommended tire rotation provided by the Highland Park Service Center.

View attachment 60200

Crisscross or front to back rotation methods are both acceptable and neither are superior (regardless of the urban legends you might have heard). As to not using crisscross rotation for directional tires, it depends on what kind of directional tires you're talking about. There are two kinds. One kind (casing directional) must be crisscross rotated, If they are casing directional and asymmetrical they will have an A and a B tire. (Note that most directional tires are not casing directional).

 

[dsm363]

Crisscross or front to back rotation methods are both acceptable and neither are superior (regardless of the urban legends you might have heard). As to not using crisscross rotation for directional tires, it depends on what kind of directional tires you're talking about. There are two kinds. One kind (casing directional) must be crisscross rotated, If they are casing directional and asymmetrical they will have an A and a B tire. (Note that most directional tires are not casing directional).

I thought Tesla only did front to back rotation for the 21" Contis at least.

 

[jerry33]

I thought Tesla only did front to back rotation for the 21" Contis at least.

They had to put in some way to rotate the tires in the manual, and front to back is easiest because you only have to raise one side of the car at a time (assuming there is no lift available). But technically, there is no advantage to either method unless the tires dictate one or the other.