2021 MYLR Dual Motor: grinding/squeal when shifting into Part

[Pianewman]

46k miles: Every time I shift into Park, I hear a grinding/squeal, coming from the rear wheels...I think...If this were a conventional braking system, I'd be looking for a place to lubricate the parking brake cable/mechanism.

Service Center says the parking brake mechanism needs to be "calibrated", a minor service.

Thoughts?

 

[Pricedm]

Could be the parking brake (aka rear brakes) need routine service. My brakes had a squeek when engaging parking brake. A quick DIY service (follow the manual) resolved the issue. Either DIY or have your service center do the routine brake service.

 

[GtiMart]

Your car does use the rear brakes as the parking brake. The rear calipers are activated electrically but that ends up just pushing the pistons. Tesla already recommend cleaning / lubricating the brakes yearly, at least in harsh climates like where I live. How long has it been since your last brake clean/lubrication?

 

[Pianewman]

GtiMart: BUSTED! Never serviced the brakes. I'll let the tech do it this time, and follow up with my own service in the futurie.

I live in a salt-free climate, car has spent only a few miles on liquid applied chemically treated roads.

I think y'all have answered my question. Thank you!

 

[Pianewman]

So, I visited Tesla SC on Aug. 4. Service Center confirmed the noise, said rear brake calipers need replacing.

Text from Tesla: "...the parts are in. Scheduled for service Sept. 27, 7:00am"

Took the car in this morning. Different tech evaluates the sound, says, "It's normal. No service needed."
2nd tech: Ditto
3rd tech (5 years with Tesla): "The excessive noise simply means the rear parking brake actuators need to be calibrated."

While I wait, he says, "Why didn't they do this for you when you brought it in Aug. 4? If the actuator isn't calibrated periodically, it will make excessive noise. FYI, I've never seen an actuator that has failed, they just get noisy."

He calibrated the actuator (twice). The screaming scrunching sound is eliminated.

So, they were planning on replacing BOTH rear calipers, which have the actuator built-in. I'm glad they didn't throw away perfectly functioning expensive parts.

 

[Pianewman]

Well, so much for "calibrating" the rear brakes. The brake actuator scream is back. It's significantly louder than than a "normal" actuator sound.

I plan to camp at an RV park. The sound is loud enough to wake the dead. (Yes, I know, I only have to do it when I shift from D to P, but that might be at 1:00am!)

Is the rear parking brake actuator serviceable? Is there some way to lubricate the squealing part? Is the actuator replaceable?

I'm now thinking I should let them replace the calipers, unless someone knows of a solution to this noise.

 

[GtiMart]

Did you ever service the brakes to clean and lubricate everything? Just in case it's something other than the actuator that's making the noise when the piston is pushed? Do you have any noise when you brake relatively hard in normal driving?

EDIT: Do you also get the noise when going from P to D? That should move the same actuators in the other direction.

EDIT EDIT: What about when you hold the park button after putting in park (e.g. the "parking brake"). Does that make additional noise?