Ride height and tire wear /energy usage

[R1Bill]

I'm sure that this has been covered before but wasn't able to find the conversation with the search engine. Will tire wear increase significantly if I go to a lower ride height at highway speeds? I have 21" wheels and have been using the standard ride height. I wanted to try a lower ride height on longer to see if my energy use decreases. Has anyone come up with some numbers for energy use reduction at a lower ride height?

 

[scottm]

I'm sure that this has been covered before but wasn't able to find the conversation with the search engine. Will tire wear increase significantly if I go to a lower ride height at highway speeds? I have 21" wheels and have been using the standard ride height. I wanted to try a lower ride height on longer to see if my energy use decreases. Has anyone come up with some numbers for energy use reduction at a lower ride height?

Car is designed to run hiways at low height setting... there's even an auto-trigger setting to do it.

Don't think it's going to change your tire life expectancy. The earliest P cars had a different suspension setup and inside edge tire wear on rears was an issue.. Those days are long gone and I think Tesla now has the geometry right for your 2017.

You might save around 1% efficiency with low setting, somebody did an experiment once with controlled conditions.. but really, your driving style being a tiny bit more aggressive or inconsistent on the same road can blow off 1% efficiency.

Pump your tire pressure up 4 lbs for even more efficiency, but firmer ride.

Low just looks cool.

 

[Dithermaster]

The earliest P cars had a different suspension setup and inside edge tire wear on rears was an issue.. Those days are long gone and I think Tesla now has the geometry right for your 2017.

Is there any confirmation on that?

 

[linkster]

Is there any confirmation on that?

Yes, me (6+ year P85 gearhead most modded suspension owner).

RWD S cars were a hot mess WRT to excessive camber and L to R spread. Without getting into the various suspension mods (both front and rear) I performed along with other strategies to double or triple the service life (I am on my 2nd set of (now staggard) 21s with ~ 85K miles on the car that will easily take me past 100K) the dual motor cars do a nice job of spreading the working load to all four corners thus reducing premature inside rear tire wear. But yes, the lower your car, the increased camber/scrubbing/heat/wear will reduce the tire life. I can not tell you by what amount though.

btw, I never drive in low except for the first several months of ownership when all SAS cars were forced into low at highway speeds.

 

[Dithermaster]

Cool, thanks. I'm likely transitioning from a P85+ to a P100D and managed to burn through a set of 21" staggered rears in the P85+ in just two summers, so I've avoided "Low" but am looking forward to being able to use it again!

 

[linkster]

Your welcome. I would enjoy owning a P85+ over my P85 since you have the more robust Gen II rear suspension that tracks superior than the previous S cars especially under high acceleration loading. It is so darn good, it became the standard in all S cars. I am such a low tech old school dinosaur that I prefer the “classics” since a) I prefer RWD cars in non-ski areas of the country, b) I enjoy driving, and c) I don’t have to listen to the racket of Nanny/Elon beeping at me and sending me visual warnings every singe tIme I pull my LR RWD M3 (optioned with the full suite of self driving shaboli) in and out of my own garage.

WRT to highway efficiency, I don’t believe that the P85+ cars exhibited the increased range over the other cars as claimed by Tesla nor do I believe that driving in low nets much appreciable increase in range. I was ~ 275wh/mi lifetime on square 21s with suspension mods, reduced camber/toe alignment settings along with increased tire pressures for the first ~50,000 miles and now running ~305wh/mi on staggard 21s. Wheel diameter (smaller is better) and wheel/wheel cover design seem to be big factors in adding additional range.

Enjoy your new incoming new S!

 

[St Charles]

Make absolutely sure that your wheel alignment is 100%. If your toe is off by even a little bit, you'll scrub the inside of your tires bald quickly.

Tesla's suspension geometry is designed around the low setting. Sometime a few years back, an update revised the standard setting to be a bit higher which, in theory, was to prevent battery strikes from road debris. The suspension was never redesigned for this update causing premature wear.

Credit: @sorka

 

[scottm]

Tesla's suspension geometry is designed around the low setting

..so much so that, in fact, the graphic of the car on the suspension tab more closely shows what the original intent of the ride height which was 3/4" lower than it is today.

i.e. with the car in Standard height, get out and look at the wheel top to fender clearance on the front... the picture inside shows a car with much less clearance than what it really is on the street. You actually have to put the car in Low to achieve what Standard height picture is showing on the UI.

I fixed this UI error by installing lowering links. Now, the car diagram actually reflects the reality of what the car looks like outside.

 

[sorka]

..so much so that, in fact, the graphic of the car on the suspension tab more closely shows what the original intent of the ride height which was 3/4" lower than it is today.

i.e. with the car in Standard height, get out and look at the wheel top to fender clearance on the front... the picture inside shows a car with much less clearance than what it really is on the street. You actually have to put the car in Low to achieve what Standard height picture is showing on the UI.

I fixed this UI error by installing lowering links. Now, the car diagram actually reflects the reality of what the car looks like outside.

Yup. Same here. My guess is that they intentionally did this so people wouldn't notice the graphic on the MCU and get upset that it now looks higher...because it is...but not on the graphic.

 

[R1Bill]

So yesterday I did a long drive in pretty heavy traffic with my suspension set to lower at 50 MPH. Much of it was spent in the 50-65 mph range. And I really behaved myself. The results were pretty hard to believe so I will have to experiment more but before I was squarely in the middle of to 300 w/mile range. Now I'm definitely in the 200 range. Even saw something that you wouldn't believe without a picture so see below!

 

[Lasttoy]

I wore out RR in 3 months, 3k miles. I had lower set at 65. I wore out second RR . I called Tesla. This before Draper and got man in Fremont. Transferred to suspension engineer. He thinks my camber goes off in lower mode. He didn't know why. I took it off lower mode and have not had any problems.
Oh, the only adjustment to rear tires is a very slight toe on top front suspension arm.

 

[Lasttoy]

Forgot pic
No other adjustment on rear suspension alignment.
No adjustment on lower A arm.

 

[yobigd20]

The low suspension setting absolutely destroys tire wear. I know this from experience, as well as confirmation from Tesla. I've gone through 5 sets of tires over 185k miles. I had always forced the low setting, but after ~10k miles on each set they all developed severe warping/feathering leading to a very poor ride quality and insane tire noise. It wasn't until the last 2 sets (winter and summer set) that I found this out and disabled the low setting completely after I had driven about 8k miles on them and they started feathering already. After I disabled that, those tires stopped getting worse. And before someone says "check your alignment", I've had it aligned about 7 or 8 times, so that's not the issue.

The problem is not as bad now as it used to be though, because the 'original' (2012-2013) low settings was MUCH lower than the current low setting. Some time around 2013/2014 Tesla disabled low suspension for a few months while they decided on what to do to address this issue, and eventually gave it back to us in a crippled state (low is not really low anymore, they changed the height to be a lot higher than it was). They marketed it as addressing the 'running over tire hitch causing fires' issue but in reality they used that as an excuse to mask the tire wear problem. They'll never confirm that to you though, but I got that info from Tesla higher-ups directly once and they told me not to tell anyone. Basically the low suspension puts more stress on the inside of the tires leading to very bad irregular wear patterns. So don't use it unless you want to deal with bad wear and poor ride noise.

 

[scottm]

The low suspension setting absolutely destroys tire wear. I know this from experience, as well as confirmation from Tesla. I've gone through 5 sets of tires over 185k miles. I had always forced the low setting, but after ~10k miles on each set they all developed severe warping/feathering leading to a very poor ride quality and insane tire noise. It wasn't until the last 2 sets (winter and summer set) that I found this out and disabled the low setting completely after I had driven about 8k miles on them and they started feathering already. After I disabled that, those tires stopped getting worse. And before someone says "check your alignment", I've had it aligned about 7 or 8 times, so that's not the issue.

The problem is not as bad now as it used to be though, because the 'original' (2012-2013) low settings was MUCH lower than the current low setting. Some time around 2013/2014 Tesla disabled low suspension for a few months while they decided on what to do to address this issue, and eventually gave it back to us in a crippled state (low is not really low anymore, they changed the height to be a lot higher than it was). They marketed it as addressing the 'running over tire hitch causing fires' issue but in reality they used that as an excuse to mask the tire wear problem. They'll never confirm that to you though, but I got that info from Tesla higher-ups directly once and they told me not to tell anyone. Basically the low suspension puts more stress on the inside of the tires leading to very bad irregular wear patterns. So don't use it unless you want to deal with bad wear and poor ride noise.

But you're a P85 which is a known tire chewer... and quite a rare car.

Any newer P/D variant, as the original poster of this thread has, doesn't show the same issues in low setting. Tesla fixed the suspension issue by moving away from whatever P85 had.