Rotors warping 3rd time in 7 months.

[Kirch]

Turn off 1P and see if the same thing happens at 50mph when releasing acc. pedal. If it does, then maybe something in suspension or tires. If it only happens in 1P, then maybe something with drivetrain (motor / diff).

Thanks I will try that and see… I feel like if it only happen in 1Pd then it’s something to do with the drivetrain.

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[OH2AZ2OH]

You can verify warped rotors by shifting into Neutral at speed and then applying the brakes. There is no regen in neutral, so you will only be using friction braking.

Since the regen does rely on electromagnetic resistance and that resistance will change based on rotor clearance, maybe warped rotors feel similar with regen braking???

Bedding the brakes properly with EVs is a little tricky since so much of the braking is done with regen and not with the friction pads. Way way back when the first MMEs were being delivered, there was a thread about this. Basically, I did 4-6 consecutive 45mph to 0 stops in neutral soon after I got the car(make sure no one is behind you!). Maybe try that to see if that helps after the next pad change?

I have not had any luck with machining rotors. They usually aren't thick enough now to bother. Rotors are rotating mass, so making them thicker than needed reduces range/MPG. And thinner rotors warp even faster.

 

[azerik]

That’s what I’m thinking, but the feel like I’m being gaslit by the Ford dealerships

Hey, so I've been dealing with the shake of this car for, well far too long and for far too much money. I came to realize I have:
1 if not both front axles can plunge in and out by hand if I lift the car. (this isn't right as they should also NOT make a metal klanging noise when I push and pull them in and out about 1mm. )
1 or both front wheel bearings are probably going. The shake I get should not happen in the steering wheel as I let off.
The way to check, and of corse I JUST thought of this now is to toss it in N and lift off the go pedal at about 60'ish. There would be nothing but coasting, or at least should be nothing. I figure this is probably the best way to double check the wheel bearings/axles.

You can also get on a brakes a bit in N without regen, this would be rotors only (or wheel bearing, like in my case) if the shake is there on the breaks I'd be looking at rotors/bearings. The bearings could shake as the rotor would vibrate from a worn bearing.

If theres not shudder, while coasting, pop it back in drive and stay off the pedals and see if it shakes(in 1pd) . If it does it's NOT rotors but axles/wheel bearings some other driveline thing as this is in the regen mode (I had this terribly when i first bought the car. It's better now)

My car, I've started calling Hyde. As sometimes it's smooth and wonderful, and other days it does whatever it wants. And from what I've heard, this is only a joy that the 2021's got, along with the kick to open and parking anti-sistant.

(I know my left rear axle nut was loose. It should be 142ft/lbs but was probably 90~100. My left rear axle clanks hard under accelleration and will need to be fixed. Thankfully I bought a 8/100k/$0 ESP but I'm so insanely reluctant to use it.)

 

[MG101]

If you're at 100% state of charge 1pd will engage the friction brakes. Noticed it the first time this year. Could be wrong but I think it was part of an update.
I've had a pulsation for a while since I rarely touch the brakes. I also rarely charge to 100%. I put 2 and 2 together when I felt the brake pulsation at 100% soc while braking with 1pd and it going away after it dropped a percentage or two.

 

[Kirch]

You can verify warped rotors by shifting into Neutral at speed and then applying the brakes. There is no regen in neutral, so you will only be using friction braking.

Since the regen does rely on electromagnetic resistance and that resistance will change based on rotor clearance, maybe warped rotors feel similar with regen braking???

Bedding the brakes properly with EVs is a little tricky since so much of the braking is done with regen and not with the friction pads. Way way back when the first MMEs were being delivered, there was a thread about this. Basically, I did 4-6 consecutive 45mph to 0 stops in neutral soon after I got the car(make sure no one is behind you!). Maybe try that to see if that helps after the next pad change?

I have not had any luck with machining rotors. They usually aren't thick enough now to bother. Rotors are rotating mass, so making them thicker than needed reduces range/MPG. And thinner rotors warp even faster.

The rotors are definitely bad. I will try that whenever I put new rotors on. My main issue was with the one panel drive shaking, and I thought the rotors were going bad so I pressed hard on the rotors to see if the rotors are going bad. Then I think ended up warping the rotors because I thought because of the one pill drive shaking. I’m looking into some more high performance rotors but when I get them, I’ll make sure to try that. A funny thing is for never mention. Hey, here’s a good way to break in the EV’s rotors cause they go bad easily. They didn’t say anything about it.

If you're at 100% state of charge 1pd will engage the friction brakes. Noticed it the first time this year. Could be wrong but I think it was part of an update.
I've had a pulsation for a while since I rarely touch the brakes. I also rarely charge to 100%. I put 2 and 2 together when I felt the brake pulsation at 100% soc while braking with 1pd.

oh wow didn’t even think of that… I will test that out when I get back to Knox.

 

[Fixbear]

If you’re going above 50 miles an hour whenever the car‘s been sitting for a while and you just let take your foot off the pedal completely and let the engine slow it down. The steering wheel will shake really fast left and right about an inch each direction. I know my rotors are bad so I didn’t know if the one pedal drive somehow activated the rotors or the brakes to slow down or not. If that’s the case then my rotor is being fixed. We’ll solve this issue however I was told that one pill driver does not use the brakes or the rotors so then then I was like well what causes the one power drive to shake if it’s not the rotors or the brakes. Sometimes a slow speeds are definitely feels like somethings like catching every few inches like. As this is my first electric car I’m really not sure how that’s supposed to sound.

One pedal uses excitement of the rotor in the motor to slow down. not brake calipers. I'd have the CV joints inspected. Also double check your tire pressures. some brand of tires are more rigid than others and it underinflated have a memory flat spot till the tire warms up.

 

[tls]

I realize I'm responding to...not the youngest thread...here but I want to raise one possibility that seems to not have been mentioned - uneven overtorquing of the lugs. Final tightening of lugs should be done with a torque wrench, not an impact gun. Overtorquing can cause residual stresses that will warp the rotors with much less heat than it should otherwise take. The impact gun should be used with a torque limiter bar flexy enough to leave a noticeable amount of rotation of the lug available for final hand tightening with a good torque wrench. Just using a torque limiter bar of exactly the final value isn't good (but it's what a lot of shops do) but slamming the lugs on with an impact gun and no limiter is pretty bad and it happens all the time. Next time anyone here heads down the $1000s of repeat brake jobs route...consider retorquing the lugs yourself and see what happens.

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