"Groaning" sound while in slow reverse

[Damager99]

I have a 2015 Model S 85D. When I slowly reverse down the driveway, especially first thing in the morning, I get a rather loud "groaning" sound from the backend. If I slam on the brakes, it seems to help, so I think it has something to do with my pads, but I'm not sure. I don't experience any sound in Drive or when reversing most of the time.

Any insight? Thanks...

 

[GWord]

What size wheels do you have? After market wheels and even some Tesla factory wheels will rub the plastic fender lining when going in reverse at certain steering angles. The tread on the tire can make a sort of groaning/buzzing noise when this happens.

 

[cypho]

Do you park outside? If your brakes get wet (rain, dew, carwash) rust can cause them to stick closed.

 

[Damager99]

I run 19's right now. I don't park outside, but it DOES seem like the groaning is more prevalent when the car has been parked wet in the garage.

 

[dark cloud]

I run 19's right now. I don't park outside, but it DOES seem like the groaning is more prevalent when the car has been parked wet in the garage.

if it is rust on your rotors, then it will be on the front and rear, and you will be able to see this on the rotors after parking it with water on the brakes, or in a high humid environment overnight. Next time just look at the rotors surface, see the rust on the surface, and your first brake application will make a scraping/grinding sound. This is not unique to Tesla rotors.
Or try this: next time it happens drive around the block after leaving the driveway, re-park and leave again. If the sound is gone that is probably what it was.

Here is another question: does the car feel stuck when moving it after sitting for a while in the garage? Do you have to give it a little accelerator to get it to move, and hear a cracking or thud sound? That is rust also.

 

[Damager99]

Thanks all...

 

[Damager99]

I took the car to Tesla Service and it turns out they needed to replace both rear wheel parking brake calipers. Was covered under warranty. Groaning sound is gone.

 

[dark cloud]

I took the car to Tesla Service and it turns out they needed to replace both rear wheel parking brake calipers. Was covered under warranty. Groaning sound is gone.

Thanks for posting back and letting us all know. If you don't get those ones serviced annually, along with the regular braking callipers, they will most likely seize up in 5 years just like the last ones.