Air Suspension no longer lowers at highway speeds (FW update v5.8)

[realeezz]

Someone asked about the difference in ride. I was aware something was wrong the day it downloaded. The ride was stiff and the handling was noticeably worse. It seems to be a shade higher than the old standard setting. I'm sure the stiff ride comes from the fact that the airbags are much harder than before.

It is not comforting to see they changed the wording in their advertisement, I will be preparing in the event that I am denied my property back!

 

[lolachampcar]

I've spent some time with the air and coil suspensions. Part of that time was trying to understand why the damper valving was so different between air and coil springs (see graphs below).

It appears as though Tesla is relying on the spring to support the car in coil spring applications. This makes sense to me given that a coil requires a certain amount of pre-load to maintain ride height and a given spring rate to maintain a minimum ride height at gross weight. Neither of these requirements would likely be ideal for a given set of handling or ride characteristics.

I think air springs give designers more freedom. Ride height can be set by the volume of air in the assembly. Assuming the geometry of the assembly does not change throughout the stroke, simply changing the volume of air (not the pressure) allows the car to change ride height. This allows the spring rate to be lower than a coil while still achieving ride height goals. The same theory applies to supporting the car fully loaded. Sure, the air pressure will increase in the assembly increasing the rate but only enough to support the car. In short, I think air decouples spring rate choice from maintaining ride heights more so than coil.

I am no street car suspension expert and have only looked into it because of my interest in MS. The above is based on observation and I would love for someone more knowledgable than I to chime in here. If I am correct, air cars should not change spring rate with an increase of 8/10s in ride height. In addition, the dampers appear to be mostly linear in stroke so I would not think there would be a change in ride from them. The car should feel the same at the two different ride heights which mine seems to do.

 

[darthvdr]

It is very disturbing that I had to find out about the affect of 5.8 over tmc instead of Tesla informing us before we upload the new software. Very Very disappointed.

 

[Doug_G]

It is very disturbing that I had to find out about the affect of 5.8 over tmc instead of Tesla informing us before we upload the new software. Very Very disappointed.

That's not what bothers me. I understand that there might be some complexities in displaying the release notes prior to upgrading. They'd have to post it to a web site or partially unpack the update so that the text could be displayed.

What bothers me is that the release notes did not explain the changes in air suspension. That is such a huge oversight I can only conclude it was deliberate.

I don't expect them to explain every little change to every algorithm. But I do expect them to report substantive changes to the car's operation, not just its user interface.

 

[jerry33]

That's not what bothers me. I understand that there might be some complexities in displaying the release notes prior to upgrading. They'd have to post it to a web site or partially unpack the update so that the text could be displayed.

What bothers me is that the release notes did not explain the changes in air suspension. That is such a huge oversight I can only conclude it was deliberate.

I don't expect them to explain every little change to every algorithm. But I do expect them to report substantive changes to the car's operation, not just its user interface.

Releasing something that was relatively bug-free would also be nice. Seems like 5.8 could be given to the Smithsonian to use as part of their ant-farm display.

 

[scaesare]

Incidentally, I was able to experimentally confirm yesterday that at 100+MPH the center condole Driver Settings​ screen will indeed indicate a transition to "Low".

Given the conditions of that experiment, however, I was not able to independently confirm that the actual suspension mechanics indeed did perform the transition indicated on the console.

 

[realeezz]

you paid the difference to get it, HEllo

 

[gnelson]

That's not what bothers me. I understand that there might be some complexities in displaying the release notes prior to upgrading. They'd have to post it to a web site or partially unpack the update so that the text could be displayed.

What bothers me is that the release notes did not explain the changes in air suspension. That is such a huge oversight I can only conclude it was deliberate.

I don't expect them to explain every little change to every algorithm. But I do expect them to report substantive changes to the car's operation, not just its user interface.

Your expectations are entirely reasonable and should have been met. In addition I expect Tesla Motors to address the vulnerability of the battery pack. There is no assurance that a suspension setting change will prevent damage to the battery pack.

 

[JRP3]

There is also no assurance that an extra layer of protection on the pack will prevent damage. Again, Tesla cannot build a tank, there is always risk in an automobile, the question is what is reasonable.

 

[Al Sherman]

The pack isn't any more "vulnerable" than the flimsy botom of any ICE car. More than likely it's much LESS vulnerable.

 

[lolachampcar]

I keep coming back to the notion that having the battery on the bottom of the car makes MS work. It also makes for a very large somewhat fragile target for debris. By fragile, I mean that you can dent the bottom of an ICE without doing $40K to $50K in damage. You can cause a small tear in the bottom of an ICE without as much of a chance of causing a fire. The ICE fire target is simply smaller (oil pan or fuel tank) than it is on MS.

If the above is true, the thing that stands out the most to me is that the risks associated with MS are financial in nature and not safety. The way the pack is designed and managed gives the occupants warning and time to safely exit the vehicle thus there is no safety hazard. Once you remove safety all that remains is financial.

Tesla has removed the financial element of fire damage but then this was small to begin with. The real exposure for me is the financial exposure of such a large target being susceptible to damage who's cost is disproportionate to the damage. I think when all the hubbub dies down we will eventually see this issue rise to the surface.

 

[JRP3]

That probably depends on the actual frequency of pack impact damage. The 1/4 inch thick aluminum should be able to take a lot of force without damaging the pack.

 

[SCW-Greg]

Incidentally, I was able to experimentally confirm yesterday that at 100+MPH the center condole Driver Settings​ screen will indeed indicate a transition to "Low".

Given the conditions of that experiment, however, I was not able to independently confirm that the actual suspension mechanics indeed did perform the transition indicated on the console.

On our road trip to Seattle this week, I did confirm it's transition at 97mph, twice. I've never been able to tell when the car lowers at highway speed, but I do know what it feels like when it raises back up... and I could tell that it did actually raise back up, when we fell below 65 mph. So I'm certain it's working.

I does make for a difference in ride quality, once you're aware of it.

 

[brianman]

(1) I know there's a distinction between (a) and (b), but I'm not sure precisely what it is. (2) Does your car go into Low at least when you have your foot on the brake?

(1) By "engage in Low" (a), I mean the UI shows Low is active (rather than popping back to Standard and reporting an error). This is different from (b) which means the car is actually doing what the UI says it's doing.
(2) Sometimes it does (a) in that case. Sometimes it give me the error messages and pops back to Standard (b).

Since 5.8 I don't have any personal or video evidence of the vehicle suspension every becoming actually lower (to the ground) even when the UI finally gets past finicky to show me "Low".

Also, regarding "video evidence" I posted a trip I took the day 5.8 came out where several times I had the UI get to "Low". Included is footage of the car undercarriage where I do not see clear evidence of the car moving into a 4th position ("Low") at any point despite me having seen it in the UI at least a few times on that trip.

- - - Updated - - -

The wording may be more for future purchasers than existing owners.

Yes, but I think this is a troubling practice. A handful of features that were present on the TeslaMotors.com pages have been modified or removed. It weren't for screenshot captures on TMC or archive websites, it presents a problem of "revisionist history" for existing owners.

 

[lloyds]

Outa curiosity, anyone not upgrade to teh 5.8, but noticed that the car sits higher? I've noticed that in Standard my car sits higher than before, but I have not updated to 5.8.

 

[tomas]

Outa curiosity, anyone not upgrade to teh 5.8, but noticed that the car sits higher? I've noticed that in Standard my car sits higher than before, but I have not updated to 5.8.

Perception is reality. Perception influenced by forum. Ergo, forum is reality. Kind of.

This has not been reported by anyone else, and in fact there are quite detailed measurements earlier in thread of pre-post 5.8 physical measurement of ride heights. So, I doubt this is anything more than forum-induced mania. Still, it sure would be ironic if it turned out ride height changed in earlier releases and nobody noticed/cared until 5.8.

 

[scaesare]

On our road trip to Seattle this week, I did confirm it's transition at 97mph, twice. I've never been able to tell when the car lowers at highway speed, but I do know what it feels like when it raises back up... and I could tell that it did actually raise back up, when we fell below 65 mph. So I'm certain it's working.

I does make for a difference in ride quality, once you're aware of it.

My...uh... "closed course test track location" was rather short and not terribly smooth, so I really didn't have the opportunity to discern. Good to know that the actual mechanicals are following what the console indicates however... thanks.

 

[Mobster]

I have read most of the posts here since Elon's blog went live. IMHO, our discussion is neglecting two of the most important questions:

1. In the "January" update that gives the driver "full control" will the new low setting be equivalent to the 4.5 low setting or will it be higher?

2. Will the "January" update actually be pushed to all cars in January or will it actually take several more months for all cars to receive it (as has been Tesla's MO recently).

We had a lively discussion here with many references to stay calm and Elon will give us back the promised lowering (as before, not modified) in January. Like many, I hope this happens. Soon. And..... it returns us to the previous state before the poorly executed "PR move". Well, January is hours away and in the mean time we have had 2 software downloads (good ones -- thanks Tesla). Lets have our feature back SOON. (Not a rant, or panic. Love the car. Expect honest, straight forward dealing from the company. Just an opinion.)

 

[Mayhemm]

Well, January is hours away and in the mean time we have had 2 software downloads (good ones -- thanks Tesla). Lets have our feature back SOON.

I don't know whether I agree with this or not. The automatic lowering of available current in FW 5.8.4 designed to prevent the car from drawing too much power on "suspect" (re: shoddy) circuits seems like a good safety move on paper. However, several reports indicate that it may be over-sensitive and reducing charge power on circuits that received full power before the update. The real-world implications of this are that many charge locations could see a reduction in available power (and, thus, increased charging time). Hopefully, Tesla will remedy this soon because I doubt people are going to redo their wiring just because the car says there might be a problem. Personally, I'd rather see this fixed than the suspension since there is more widespread effect (noticeable increase in charge time versus minor change in high-speed dynamics).

 

[andrewket]

Well, January is hours away and in the mean time we have had 2 software downloads (good ones -- thanks Tesla)

I disagree as well. I'm still running 5.6 because every release since then has been problematic. Air suspension, charge current reduction, sleep mode issues.

I just returned from a week long trip. I left my MS at the airport. Sleep mode worked great; I lost very little range. Had the car not gone to sleep I likely would not have has the range to get home without stopping to charge somewhere. This was at 9pm with a very tired family in tow.

We need a stable and functional software release after 5.6.