Nasty noise on hard acceleration

[St Charles]

I did this for the first 3 cv shaft replacements. Put it into auto lowering to lowest at all speeds. Only ever raised to to get over specific speed bumps and curbs and canceled all auto saved height geo locations.

Made no difference. The issue came back every time....until I lowered the car ONE MORE INCH with lowering links 50 miles after the very last cv shaft replacement....which has now been 14K miles and not a hint of the issue returning.

This is very interesting. It seems that perhaps the CV joints are a bit too close to their maximum angle at standard height. The creaking probably has to do with the front end lifting on hard acceleration bringing the CV joint further out of alignment. The real fix is probably to lower the front motor a bit to correct the angle of the half shaft. In the ICE world, you would fix this with redesigned motor mounts which lower the motor and trans-axle. I wonder if there is something that prevents this solution in the Model S/X?

Have there been any documented CV joint failures related to this issue?

 

[sorka]

Have there been any documented CV joint failures related to this issue?

That depends on what you mean by failure. I'm not aware of any snapped shafts or joints.

 

[St Charles]

That depends on what you mean by failure. I'm not aware of any snapped shafts or joints.

I mean catastrophic failure of the part. Something that strands you on the side of the road. I'm betting these CV joints don't like transferring torque when they are out of alignment and we are hearing NVH as a result. I like your idea to bring the front suspension back into alignment with lowering links.

 

[sorka]

What length lowering links do you use?

Complicated answer but here:

3D printed lowering links

 

[Zesoloist]

I have a 2018 MS 75D and its made this noise every time I've pulled out into traffic. Not hotrodding. Starts around 30mph and lasts till 55/60 mph (if I'm accelerating on an on-ramp). Asked my SC (Las Vegas) and they said its a know fault but since its not a hazard to not expect a recall. I remember my SC saying something about 100s getting 'it' (I think he said the drive box) fixed when they come in for other work. If they want to pull all my diagnostics and show me the 'hotrodding' Id be fine with that. But it seems this is bordering on some type of lemon law issue. I always drive with standard height suspension. If the solution is driving in Low, Tesla needs to send notice to all owners.

 

[St Charles]

I've had issues any time I push more than 250kW to the motors while under 60MPH. After reading this thread, I tried low suspension settings which resolved the noise. I'll probably just leave the suspension on low from now on.

 

[Blue steel]

Brand New Tesla 75d Oct 18.

Because of only one service centre in our country car was picked up and taken to Auckland. After being there one month and having suspension replaced and rear motor. After being insistant it came back with the dreaded acceleration noise! And what's worse I told them about it! Didn't believe me and wanted proof. I have sent them proof today but then found this forum! Sent them the link. No doubt nothing will be done? Or another month no car . Honestly why did I have to find the proof when it was easy to find the issue for me using my uncle Google!

 

[sorka]

16K miles and it still hasn't returned. Daily ludicrous launches.

 

[dk10438]

any new developments on this? I recently purchased an inventory P100D and have the sound on hard acceleration. Specifically is there a permanent fix? I don't want to take the car the the SC if the issue can't be fixed...

Strange noise on full throttle acceleration. Any ideas??

 

[Dragetreneren]

any new developments on this? I recently purchased an inventory P100D and have the sound on hard acceleration. Specifically is there a permanent fix? I don't want to take the car the the SC if the issue can't be fixed...

Strange noise on full throttle acceleration. Any ideas??

The new parts are coming, but it is unknown when is what I heard.

 

[Mobster]

A couple of months agoI had my MS P100D in for yearly service and for the first time they took a crack at fixing it. And...it worked. Then a couple of weeks later it was back. (note: the Tesla Model S loaner they gave me had the same acceleration knock)

 

[Congo Line]

My car hasn't made the sound for a while now. Not sure why, but I did replace the front tires during that time. Is it possible that it's the motor cutting power intermittently if/when the wheels slip on hard acceleration? It does sound a bit like when ABS kicks in.

 

[michal54]

How do you hotrod a Tesla? I'd like to know so I can raise it up to the 691 hp that they advertised it at before we all found out they lied and retroactively changed it to 463 hp which is what those of us who were dynoing our cars had been saying all along.

Or by hotrod, do you mean accelerating hard? Would I be Insane to ask for a refund on my Ludicrous upgrade so I'm no longer hotrodding it

I've had my front cv axles replaced 4 times. The first 3 times the vibration returned within 3 or 4K miles miles. I'm at 13K miles or so now and it still hasn't returned.

I'm pretty sure it's because I hotrodded(er I mean) lowered the car 1" reducing the angle the cv joint is under during maximum torque.

I can not say what is meant by the technicians's use of the word "hotrod". But when I picked the car up, another tech told me to lower the car when accelerating. So, your lowering the car was the right thing to do. However, I don't "hotrod", accelerate hard, punch it, etc. I first noticed the noise when accelerating to get out of the way of an oncoming car in an intersection. I didn't have time to put it in "low" suspension. The noise has not returned, but I also haven't accelerated too hard. I don't want to pay anymore than I already put out.

 

[Cory151]

My car hasn't made the sound for a while now. Not sure why, but I did replace the front tires during that time. Is it possible that it's the motor cutting power intermittently if/when the wheels slip on hard acceleration? It does sound a bit like when ABS kicks in.

Neither has mine. I believe they digitally shaped the acceleration curve (and shipped it in one of the last updates) to feed in power into the drivetrain in a more linear way. Tesla's goto is usually, "first, can we fix it over the air at no cost?"

 

[sorka]

Neither has mine. I believe they digitally shaped the acceleration curve (and shipped it in one of the last updates) to feed in power into the drivetrain in a more linear way. Tesla's goto is usually, "first, can we fix it over the air at no cost?"

I'd true then less torque which is less power in the in the susceptible speed range which means slower acceleration.

And since it happens just as bad at moderate acceleration vs hard acceleration, they'd have to have quite the reduction.

 

[Inside]

Just curious if the new Model S builds (Raven builds) with the new suspension would still have this problem?

 

[sorka]

Just curious if the new Model S builds (Raven builds) with the new suspension would still have this problem?

It's not a suspension issue.

 

[Cory151]

I'd true then less torque which is less power in the in the susceptible speed range which means slower acceleration.

And since it happens just as bad at moderate acceleration vs hard acceleration, they'd have to have quite the reduction.

I for one, was only able to get mine to make the noise at maximum acceleration. I've been running the thing a lot in the 1/4 lately and its not made a peep. Perhaps they are adjust the front end height when switching to Ludi, or changed the correction factor in the traction control to get rid of the harmonic.

 

[jaitch]

Just for the record really. I have an 2018 S75D loaner with air that does this. My coil P90D does not do make this woodpecker style noise. It sounds wrong to me and I don't really want to drive the loaner unless I have to. No car can possibly make this kind of noise and it be OK. It is engineering and physics crying out that something is wrong in my opinion. Tesla apparently say it is known about and not dangerous but can't say what it is - makes no sense. I hope they can engineer a proper solution.

 

[sorka]

Just for the record really. I have an 2018 S75D loaner with air that does this. My coil P90D does not do make this woodpecker style noise. It sounds wrong to me and I don't really want to drive the loaner unless I have to. No car can possibly make this kind of noise and it be OK. It is engineering and physics crying out that something is wrong in my opinion. Tesla apparently say it is known about and not dangerous but can't say what it is - makes no sense. I hope they can engineer a proper solution.

Tesla said it isn't dangerous? To whom? They only told me that verbally and when I asked them to put that in writing they refused and instead decided to replace the cv shafts (which was the 4th time). They weren't going to and just told me to live with until they came up with a permanent solution but then told me to come in when I insisted that they put in writing that the violate shaking wouldn't cause metal fatigue and catastrophic component failure as a result.

23K miles later and the shaking hasn't returned