Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

RWD - Noise under acceleration only

This site may earn commission on affiliate links.
S

Saabstory88

Guest
I have been trying to diagnose a noise on my 55k mi 2018 Mid Range. It has been becoming more apparent over the past 3 or 4 months. Today, I was able to finally get around to checking the torque on the rear suspension components. I also made sure to clear all debris from the aerodynamics. The noise is still apparent, so I spent an hour or two driving around to eliminate variables and get a clearer picture of when the noise occurs.

The sound has the dynamics of something becoming loaded and unloaded, as opposed to a noise with a consistent volume and frequency across the range of motion. It is reminiscent of a squeaking floorboard, and seems to be localized to the rear of the car. This is true both with windows up and down. I can not reproduce the sound under static conditions, such as applying my full weight weight, or applying shifting weight (bouncing on it) to each of the door sills as well as the trunk sill. The noise occurs when accelerating. The noise is present as the motor provides torque, then disappears as the torque loading stabilizes. It makes an additional creak as the motor torque is unloaded. The sound is not present under any acceleration in reverse. It also does not occur under light or heavy mechanical braking, as well as not during regen. It does not occur over speed bumps or on rough roads. The noise does occur when cornering and holding power constant, but does not occur when cornering in neutral. I have repeated each of these scenarios several times, and the behavior is completely consistent.

Based in this, it leads me to believe that I need to be looking at Subframe torque and lubrication. I imagine that this sound would occur in only the observed conditions if say, one or both of the rear two subframe bolts was loose, or the mating surface was not properly lubricated. If that fails, perhaps even the half shafts? Do these seem like the best next steps? Has anyone had these very specific symptoms (not just general rear suspension noise) corrected under warranty? What was the correction?
 
  • Informative
Reactions: KenC
I have been trying to diagnose a noise on my 55k mi 2018 Mid Range. It has been becoming more apparent over the past 3 or 4 months. Today, I was able to finally get around to checking the torque on the rear suspension components. I also made sure to clear all debris from the aerodynamics. The noise is still apparent, so I spent an hour or two driving around to eliminate variables and get a clearer picture of when the noise occurs.

The sound has the dynamics of something becoming loaded and unloaded, as opposed to a noise with a consistent volume and frequency across the range of motion. It is reminiscent of a squeaking floorboard, and seems to be localized to the rear of the car. This is true both with windows up and down. I can not reproduce the sound under static conditions, such as applying my full weight weight, or applying shifting weight (bouncing on it) to each of the door sills as well as the trunk sill. The noise occurs when accelerating. The noise is present as the motor provides torque, then disappears as the torque loading stabilizes. It makes an additional creak as the motor torque is unloaded. The sound is not present under any acceleration in reverse. It also does not occur under light or heavy mechanical braking, as well as not during regen. It does not occur over speed bumps or on rough roads. The noise does occur when cornering and holding power constant, but does not occur when cornering in neutral. I have repeated each of these scenarios several times, and the behavior is completely consistent.

Based in this, it leads me to believe that I need to be looking at Subframe torque and lubrication. I imagine that this sound would occur in only the observed conditions if say, one or both of the rear two subframe bolts was loose, or the mating surface was not properly lubricated. If that fails, perhaps even the half shafts? Do these seem like the best next steps? Has anyone had these very specific symptoms (not just general rear suspension noise) corrected under warranty? What was the correction?

it sounds like a rear subframe suspension bushing. My 2018 LrRWR had a clunking on acceleration and an unwind clunk on deceleration. It occurred at 5000 miles and repaired under warranty at the time in June2018 there were few spare parts so it was a month before a replacement rear subframe was available.
 
  • Helpful
Reactions: Phlier
it sounds like a rear subframe suspension bushing. My 2018 LrRWR had a clunking on acceleration and an unwind clunk on deceleration. It occurred at 5000 miles and repaired under warranty at the time in June2018 there were few spare parts so it was a month before a replacement rear subframe was available.

So services solution was a whole new rear subframe rather than a bushing? Does that indicate that the bushing is not independently replaceable? At least I'm not at the clunk stage yet.
 
upload_2021-1-11_9-49-51.png
 
it sounds like a rear subframe suspension bushing. My 2018 LrRWR had a clunking on acceleration and an unwind clunk on deceleration. It occurred at 5000 miles and repaired under warranty at the time in June2018 there were few spare parts so it was a month before a replacement rear subframe was available.

So much for claim that the chassis lasts "1 million miles." 5,000 is not really even in the same ballpark, lol!
 
it sounds like a rear subframe suspension bushing. My 2018 LrRWR had a clunking on acceleration and an unwind clunk on deceleration. It occurred at 5000 miles and repaired under warranty at the time in June2018 there were few spare parts so it was a month before a replacement rear subframe was available.
I was apparently the first person with a Model 3 in June 2018 that had such a clunking noise. Although I told them it sounded like a bushing they first diagnosed it as the rear drive motor and replaced it, when that did not solve it they brought in regional and national trouble shooters and concluded it was a rear subframe bushing. Problem was that in early in the model 3 production there were no spare parts and the fastest solution was a complete rear sub frame ..thus the 5 week time span. They gave me a new 2018 model S 100D to drive for 5 weeks!
 
It may not be that bad. Tesla fixed mine at the big Tesla body shop in Pomona in January 2019. They only needed to re-torque on mine (2018 performance model, took delivery in August ‘18).

No spare parts back then is right. They basically had to wait until the build lines shut down to run in and get major parts from Fremont.
 
Hmmmm... Two of the subframe bolts were well out of spec. That being said, it did not eliminate the noise. Maybe time to look at motor mounts?