Brake dust on rears vs fronts?

[Terpman90]

Have a new 2024 Model S LR that I got back in April. LOVE the car.

Installed some gloss black TSportline wheels the same week I got it, and I've noticed a strange (in my opinion) phenomenon. On my past Tesla Model 3, I got practically zero brake dust on the wheels, which I'd expect with the high regen (set to highest setting on both vehicles). On the MS, I get almost NO dust on the fronts, but the rears seem to stay heavily coated in brake dust. Anyone have any idea why? Is this common? Wondering if they're still 'breaking in' (pun intended ) and this will go away eventually, or if this is indicative of a problem? Thoughts?

 

[DerbyDave]

Maybe check the rear brake dust shields.

https://service.tesla.com/docs/ModelS/ServiceManual/Palladium/en-us/GUID-74FE97FB-42EE-4D80-8066-2B321C4FAFCD.html

 

[philip295]

Is it possible the traction control is braking the rear wheels to prevent spin?

 

[Terpman90]

Is it possible the traction control is braking the rear wheels to prevent spin?

I'd doubt it - though I'll admit I've done some 'spirited' driving. I wouldn't think that would be enough to generate the amount of dust I've been seeing. I'll keep that in mind, so thanks for that suggestion.

 

[terranx]

On other cars I've driven, this was usually a sign of a sticking caliper. Are the rear brakes noticeably warmer than the fronts when you park the car?

 

[Aggmeister2010]

Is it possible the traction control is braking the rear wheels to prevent spin?

No, for acceleration the motors cut power, not engage the brakes.

On other cars I've driven, this was usually a sign of a sticking caliper. Are the rear brakes noticeably warmer than the fronts when you park the car?

This is what I'd check. Grab yourself an infrared temperature gun and check the brake temperatures. If you see the rears much warmer than the fronts, you have a problem. When the brakes are used, the fronts take much more of the bias and therefore get hotter.

 

[Terpman90]

No, for acceleration the motors cut power, not engage the brakes.



This is what I'd check. Grab yourself an infrared temperature gun and check the brake temperatures. If you see the rears much warmer than the fronts, you have a problem. When the brakes are used, the fronts take much more of the bias and therefore get hotter.

Interesting - hadn't thought of this. I actually have a temp gun, so I'll definitely check this after a drive. Thanks for the info!

 

[dbeiler]

No, for acceleration the motors cut power, not engage the brakes.

The vehicle being discussed is a LR, not a Plaid.

A Plaid can cut power to an individual rear motor to prevent wheel slip.

A LR cannot. It has an open differential and must apply rear brake to an individual wheel to prevent wheel slip.

 

[Aggmeister2010]

The vehicle being discussed is a LR, not a Plaid.

A Plaid can cut power to an individual rear motor to prevent wheel slip.

A LR cannot. It has an open differential and must apply rear brake to an individual wheel to prevent wheel slip.

Even so, are you certain it’s applying brakes to prevent acceleration wheel slip? That seems like it would cause very very jerky motions rather than just cutting power.

 

[Usher]

The vehicle being discussed is a LR, not a Plaid.

A Plaid can cut power to an individual rear motor to prevent wheel slip.

A LR cannot. It has an open differential and must apply rear brake to an individual wheel to prevent wheel slip.

With an open diff and only one wheel slipping, cutting power to the motor will in fact only brake the slipping wheel. The wheel with grip is going to continue to go the same speed.