Premature tire wear from regen braking system

[eye.surgeon]

After driving the Model 3 AWD for 13 months and having to replace the original set of tires (18" Michelin MXM4) at 17,000, I have come to a conclusion that the main culprit is the standard regenerative braking system.

Thus, I am going to switch to the low regen mode and see a difference in tire wear. Replacing the brake pads are a lot cheaper endeavor than replacing the tires...

The majority of the mileage came from commuting with short burst of acceleration for traffic maneuvers and normal driving habits.

What do you think?

The laws of physics would disagree with your theory.

 

[TomB985]

It hasn't worked that way in 130K miles on my S, tires wear about the same front and rear. Braking with regen doesn't wear the tires out more, high speed or slow speed. Standard regen is really fairly gentle--about the same as you would normally brake.

I can't speak for the S. But standard regen is normal braking from half the tires...the half with the least traction.

There's a reason why the 3 is noted for wearing out tires long before their time. Mine have been good with regular rotation, but lots of folks kill them before their time.

 

[mswlogo]

40-42lbs cold should be fine.

AWD (which helps spread the accel and regen load) help spread the friction out and the wear out

It just doesn't make sense that the center wore out so soon. Plenty of other folks have 40K+ (RWD and AWD) and I'm sure most are putting the psi on the door tag.

Alignment or even aggressive driving would not favor the center wearing out.

Something is fishy.

For the Record I never do Cross X pattern for rotation. Always front to back.

 

[mcbarnet007]

If you care about your tire wear, make sure the Toe Alignment is as close to zero as possible front and back. Bad alignment eats tires more than anything.

 

[Paddy3101]

I can't speak for the S. But standard regen is normal braking from half the tires...the half with the least traction.

There's a reason why the 3 is noted for wearing out tires long before their time. Mine have been good with regular rotation, but lots of folks kill them before their time.

I have 20K on mine, haven't been rotated. Have even wear front/back and across the tread-width. (a little extra wear at the shoulders).
About 50% tread depth left down to wear bars.

This is on a P3D+ with the 20's. Always on standard regen, (in hold mode now). Very rarely touch the brakes in normal/commute driving, unless I am pushing on when having fun.

Regen on the RWD will obviously only be on the rear. Regen on the AWD is across both axles, until low speed (7mph) when it becomes rear only.

Regen won't be getting anywhere near the limit of traction the dry, just isn't enough regen for that. Any slippage in the wet/ice/snow will have virtually no effect on the tires anyway.

 

[3silverISgold]

From my OP, I ruled out over inflation due to using Tesla's recommended tire pressure.
When in fact, this should have been my main clue.

I am driving now with 38 PSI cold and I have not seen any noticeable difference in battery efficiency from my work commute of 30 miles each way (freeway/street/uphill/downhill). However, I do notice and enjoy a quieter and softer ride quality.

I am going to keep it here and see how the tires wear.

Mastering the one pedal driving definitely helps with tire management based on many that provided that feedback.

I just wished Tesla would add a quick access regen mode on the left of the LCD screen so we can toggle back and forth without sacrificing screen space. And perhaps even be able to set a speed range parameter, like 0-80 mph, so that the accel pedal would have greater sensitivity and control.

 

[jerry33]

For the Record I never do Cross X pattern for rotation. Always front to back.

X or F->R doesn't make any difference unless the tires have rotational arrows. F->R is easier because only one side of the car needs to be lifted.

 

[mswlogo]

X or F->R doesn't make any difference unless the tires have rotational arrows. F->R is easier because only one side of the car needs to be lifted.

Most of my tires are directional. A couple are not, but it's easier to do everything the same.
Doing the cross has caused me more harm than good.
Part of it, is if you accidentally run one direction to long, like 20K they sometimes don't like going the other way.
I rotate by season (fall / spring) with winter tire swap. Don't care how many miles. Some summers cover a lot more ground than others.

I've always got great tread life/even wear out of every tire I've ever had new. So why change what works.

If I were to cross I'd do it way more often. I'm to lazy and don't think it would eek out much more tread life.
I keep a sharp eye on pressure. And don't drive that aggressive.

 

[Occhis]

I believe the OP's initial assertion is broadly correct. Standard brakes exert a force to slow the car down by creating friction between the rotor and the brake pads. As a result, the brake pads slowly wear down and need to be replaced periodically. Regenerative braking shifts that force to the resistance between the tire and the road. This shift WILL increase the rate at which the tires wear. This is similar too, but in reverse, of the increased wear that tires mounted on the drive wheels (mostly the front wheels these days) of ICE cars compared to the wear of the non-drive wheels (typically rear wheels). Having said that, obviously driving habits (such as aggressive acceleration and slowing) will increase the rate of wear on the tires.

With regen, the motor acts as the braking mechanism, not the tires. The force exerted by the tires on the road surface is a factor of the rate of deceleration the braking system applies. That force is the same whether the braking system is motor regen or conventional brakes. So it doesn’t matter to the tires where the braking originates.

 

[GtiMart]

I was surprised with the regen when i test drove a model 3. I had to accelerate again because i was slowing too fast. If you constantly need to reaccelerate because you slowed down then you might use your tires more. The fix would be to change your habit and let go of the accelerator in a more controlled way. I know that's what I'll need to do

 

[drtimhill]

I am going to stick to my guns here. As soon as you let off the accel pedal, the tires are grabbing the pavement much more aggressively than when the car is naturally coasting.

But that was point of the other reply .. any action you make that makes the tires grip more will change the wear profile. It doesnt matter if you user physical brakes or regen, the result will be the same. What you need to change is your driving habits, and you can do that either by the way you drive or alter the way the car responds to your input. There is nothing inherently different about regen vs brakes.

 

[mswlogo]

With regen, the motor acts as the braking mechanism, not the tires. The force exerted by the tires on the road surface is a factor of the rate of deceleration the braking system applies. That force is the same whether the braking system is motor regen or conventional brakes. So it doesn’t matter to the tires where the braking originates.

That’s a really good point. When I saw the title of the thread I was expecting another RWD complain. But this time it was AWD. And I presume it’s all 4 tires that are worn out. So yeah, by definition it can’t be the regen.

And if the car was braking via regen abnormally often you’d never see the efficiencies we have.

 

[drtimhill]

I believe the OP's initial assertion is broadly correct. Standard brakes exert a force to slow the car down by creating friction between the rotor and the brake pads. As a result, the brake pads slowly wear down and need to be replaced periodically. Regenerative braking shifts that force to the resistance between the tire and the road. This shift WILL increase the rate at which the tires wear. This is similar too, but in reverse, of the increased wear that tires mounted on the drive wheels (mostly the front wheels these days) of ICE cars compared to the wear of the non-drive wheels (typically rear wheels). Having said that, obviously driving habits (such as aggressive acceleration and slowing) will increase the rate of wear on the tires.

oh come now. A tire wears as a result of friction ablating the surface. This ablation rate increases whenever the tire cannot "free roll" with the road surface, which happens both on braking and acceleration. Drive wheels thus wear more because they cannot free-roll when the care is braking AND then the car is accelerating, unlike non-driven wheels which are only impacted during braking.

As for regen vs pads, that's just silly. Both regen and regular brake pads exert a torque that resists the rotation of the wheel, which translates into a reduction in speed. The effect on the tire is the same regardless of the source of that torque. The only difference is that, in regular brake pads, the speed reduction (kinetic energy) is converted into heat (that in turn ablates that brake pads) vs electricity (that is stored in the battery). In fact, the only difference between regen and regular brakes is that regen ELIMINATES brake pad wear, which means that not only do you recover the energy to the battery, you also do it without brake wear. If the OP switches to using regular brakes he will just end up needing to replace brake pads much faster, and his battery mileage will go down significantly; it won't alter tire wear to any extent.

 

[jerry33]

I was surprised with the regen when i test drove a model 3. I had to accelerate again because i was slowing too fast. If you constantly need to reaccelerate because you slowed down then you might use your tires more. The fix would be to change your habit and let go of the accelerator in a more controlled way. I know that's what I'll need to do

It should only take about an hour's city driving to get good at it.

 

[ebmcs03]

if that's true then explain to me the difference between engine braking and regen?

Regen is much stronger than engine braking.
But I agree with you. The tire wear is probably not due to regen.

Side comment.
Plus, better way to drive a manual, when not racing, is not to downshift and use engine braking.

Better off staying in the gear you’re in when you know you’re coming to pretty much a complete stop. Downshifting will cause more wear to your clutch and everything else than using a little more brakes. (Ya ya. Some people will start the argument of Rev matching etc etc. Unless you’re Schumacher, or PDK, it’s not going to be perfect every time.)

 

[notanEVuser]

After driving the Model 3 AWD for 13 months and having to replace the original set of tires (18" Michelin MXM4) at 17,000, I have come to a conclusion that the main culprit is the standard regenerative braking system.

Thus, I am going to switch to the low regen mode and see a difference in tire wear. Replacing the brake pads are a lot cheaper endeavor than replacing the tires...

The majority of the mileage came from commuting with short burst of acceleration for traffic maneuvers and normal driving habits.

What do you think?

Hello,

I am currently doing a research regarding this topic and it is really difficult to find any experimental result or data. Did you observe less tire wear after you switch to low regen mode?

It is an interesting discussion. If someone with solid experimental results could share their opinion, it would be wonderful.

 

[drtimhill]

After driving the Model 3 AWD for 13 months and having to replace the original set of tires (18" Michelin MXM4) at 17,000, I have come to a conclusion that the main culprit is the standard regenerative braking system.

Thus, I am going to switch to the low regen mode and see a difference in tire wear. Replacing the brake pads are a lot cheaper endeavor than replacing the tires...

The majority of the mileage came from commuting with short burst of acceleration for traffic maneuvers and normal driving habits.

What do you think?

Er .. if you want my opinion .. nonsense. "Braking" is any action that causes the wheels to resist rotation. That resistance in turn puts stress on the tires, which can (and does) lead to wear. That of course is not the only source of wear (acceleration has similar effects). However, the tires dont "know" if the resistance to rotation is caused by friction (mechanical brakes) or magnetic impedance (regen braking). A certain amount of resistance will cause a certain amount of wear, and it doesnt matter how that resistance is created.

You are correct in noting that tire wear is greater on EVs than ICE cars, but this is caused by two things: (a) the weight of the car, and the commensurate necessary increase in tire pressure and (b) the much greater torque at low speeds when accelerating. You could drive your car with NO braking whatsoever (just letting it coast down by internal friction and wind resistance alone) and it would still wear tires out faster than an ICE car.

And no, you wont see a difference in tie wear by chasing regen modes.

 

[UncertainTimes]

Tire wear is all driving habits. OP's short bursts of acceleration on city streets are the main culprit of his tire wear. I’m at 34k miles on original set of PS4 on M3P and I still have 5/32 left. I do mostly freeway driving. I also got like 30k miles out of Michelin PSS on my (BMW) M3.

 

[Msjulie]

I have the original (2nd set) of Continental tires that came on my car - I don't mind a firm ride so I keep them at 45lb cold all around. I have 20k on the current set of tires and they are at most 1/2 worn. I have regen at full. I don't rocket off the line (often) nor do I slam on the brakes a lot but I do let regen do it's work.

I think driving habits, alignment and tire pressures have a greater impact on wear than regen. Oh, and I rotate them about 6-10k miles when I remember to try to keep the wear even since likely my tires will age out before they wear out given current circumstances

 

[Occhis]

My original 19” Continentals have 42,000 mostly highway miles and still have over 4/32 left. Mostly city miles will wear tires more quickly. So I think it’s also where you drive in addition to how you drive, no matter if it’s an ICE or EV.