Low speed 'Tocking' when stopping or starting

[jebinc]

25k miles on our Model Y. Zero driveline lash or strange noises. The driveline is as smooth as a sewing machine.

Same with my MYP. Buttah smooth

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[jebinc]

https://www.rivianforums.com/forum/posts/220063/

Oh my, I can’t believe how similar our stories are/continue to be! Mine was a private party purchase, so a tad less premium - I paid nearly the current MSRP for my 2xx mile used truck! I do have to take a 1.25 hour flight and drive it 6-7 hours back through several mountain passes, including Mt. Hood, but that’s exactly the mission of this truck so, looking forward to it!

 

[M4H4X]

And another one bites the dust:

https://www.f150lightningforum.com/...rting-off-either-in-forward-or-reverse.10636/

I haven’t seen a high powered EV yet where this doesn’t pop up.

Are CV spline/joint mfgs that inconsistent?

Or are high instant torque applications just not compatible with this sort of linkage?

Motor On Hub.
Rivian, Tesla, Ford, GM, hell…. Lordstown ? I wanna see it done.

 

[evhelphub]

And another one bites the dust:

https://www.f150lightningforum.com/...rting-off-either-in-forward-or-reverse.10636/

I haven’t seen a high powered EV yet where this doesn’t pop up.

Are CV spline/joint mfgs that inconsistent?

Or are high instant torque applications just not compatible with this sort of linkage?

Motor On Hub.
Rivian, Tesla, Ford, GM, hell…. Lordstown ? I wanna see it done.

The user claims the autohold mode impacts the sound they hear. I know what sound they are talking about and it's not the same thing in my R1T. The clicks and knocks are often heard 2-3 seconds after already moving forward or after regen has kicked in. I have owned a few EVs including a Model S and have never heard this amount of clicking/knocking noises. I do think the weight of the vehicle may play a role.

 

[M4H4X]

The user claims the autohold mode impacts the sound they hear. I know what sound they are talking about and it's not the same thing in my R1T. The clicks and rocks are often heard 2-3 seconds after already moving forward or after regen has kicked in. I have own a few EVs including a Model S and have never heard this amount of clicking/knocking noises. I do think the weight of the vehicle may play a role.

I agree. Weight, timing of auto hold, timing of brake engagement/disengagement in regards to regen all contribute. What I don’t know is if some drive lash is intentional given our off-road nature and that the sound is the unfortunate side effect or not.

I think Rivian could probably mitigate the issue by preloading the motors/axles when someone does a hard launch (just a few pounds of pressure to remove the slack, then the full torque unleashed).

Lots of small tweaks to minimize the noise and extend the life of the axle.

 

[evhelphub]

I agree. Weight, timing of auto hold, timing of brake engagement/disengagement in regards to regen all contribute. What I don’t know is if some drive lash is intentional given our off-road nature and that the sound is the unfortunate side effect or not.

I think Rivian could probably mitigate the issue by preloading the motors/axles when someone does a hard launch (just a few pounds of pressure to remove the slack, then the full torque unleashed).

Lots of small tweaks to minimize the noise and extend the life of the axle.

It does seem like adjustments are needed. It certainly feels like it happens most once the weight of the vehicle shifts a certain way. Oddly, it doesn't always happen on initial acceleration but seconds later which is the weird one. It has gotten worse and my R1T is only a few weeks old and about 500 miles. Started around mile 100.

 

[M4H4X]

Also to add to my previous post,

for my truck I mostly hear it the moment I press the accelerator from a dead stop, or the last few moments of slowing down (when passing down through 20mph).

That last part… Slowing down through 20. That’s when the regen begins to fade and the brakes are applied. At that moment, the torque experienced at the splines reverses from a deceleration force applied from the splines, to a deceleration force applied from the hub (the brakes), which causes the axle to shift its play, and thus the noise.

Now that you’re stopped and you press the accelerator the splines are again providing torque, which shifts the play back.

Think about that ^

 

[AdamUCF]

I had collected a handful of minor things and had the clunk sound included in that list. I was fully expecting that they would lube some stuff up and tell me it's fixed but that didn't happen at all. The service advisor (not sure if that's what Rivian calls them) at first called and said that the drive motor(s) needed to be replaced and that they had a ticket open with Rivian engineering to figure it out but they were pretty vague. The next day (Friday) they called and said that the front driver's side axle and hub needed to be replaced and that the parts would be here Monday (tomorrow).

Now I'm not sure if this is the same issue as everyone else. I haven't tried to record it from outside but from the driver's seat it sounds the same.

 

[evhelphub]

I had collected a handful of minor things and had the clunk sound included in that list. I was fully expecting that they would lube some stuff up and tell me it's fixed but that didn't happen at all. The service advisor (not sure if that's what Rivian calls them) at first called and said that the drive motor(s) needed to be replaced and that they had a ticket open with Rivian engineering to figure it out but they were pretty vague. The next day (Friday) they called and said that the front driver's side axle and hub needed to be replaced and that the parts would be here Monday (tomorrow).

Now I'm not sure if this is the same issue as everyone else. I haven't tried to record it from outside but from the driver's seat it sounds the same.

Interesting. Did you ever hear any fluttering sounds from your motors? I've been hearing more of that the last week or so. Not the usual electronic sound but one that sounds like that is it was being transmitted through a fan or something. The vehicle appears to have full power but strange acceleration sounds.

 

[R1Tom]

I had collected a handful of minor things and had the clunk sound included in that list. I was fully expecting that they would lube some stuff up and tell me it's fixed but that didn't happen at all. The service advisor (not sure if that's what Rivian calls them) at first called and said that the drive motor(s) needed to be replaced and that they had a ticket open with Rivian engineering to figure it out but they were pretty vague. The next day (Friday) they called and said that the front driver's side axle and hub needed to be replaced and that the parts would be here Monday (tomorrow).

Now I'm not sure if this is the same issue as everyone else. I haven't tried to record it from outside but from the driver's seat it sounds the same.

Is your clunk sound over bumps, or more on/off throttle related?

 

[AdamUCF]

Is your clunk sound over bumps, or more on/off throttle related?

Low speed associated with throttle press/release. Seemed pretty similar to what others have been discussing including @OutofSpecKyle.

 

[momo3605]

Anyone have clicking like this and get it resolved yet? I guess it’s more like a squeak

 

[AdamUCF]

Picking it up later. Hopefully it's fixed ?

 

[M4H4X]

Picking it up later. Hopefully it's fixed ?

It will be fixed. But it will be a temporary fix. Just have your head in that space so you're not upset when it pops up again down the road.

 

[AdamUCF]

It will be fixed. But it will be a temporary fix. Just have your head in that space so you're not upset when it pops up again down the road.

Seems like an expensive band-aid. Hope you're wrong but fear you're right.

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