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Maximum load only 420 kg/926 lbs?

Discussion in 'Model S' started by marchino, May 3, 2015.

  1. marchino

    marchino Member

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    #1 marchino, May 3, 2015
    Last edited: May 3, 2015
    max tyre pressures and load.JPG

    I just saw this photo on a thread about tyre pressures.

    Isn't a max. load of 420 kg very low for a car of this size? I weigh 100kg, so with 1 passenger also 100 kg and two at 80 kg, plus a child at say 40 kg, we already have a load of 400 kg without filling that cavernous boot.

    I would think it would be very easy to accidentally overload the car just with say an extra 5 suitcases at 20 kg each in the boot. That would be about 20% over the max. loading.

    My current car - a Mini - has a max. load of 430 kg, and it's a four-seater with a tiny boot.
     
  2. breser

    breser AutoPilot Nostradamus

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    Hey look a picture I took. I'm going to use pounds since I'm an American and I don't use your silly metric units. :scared: (actually it's just the unit that was on the Consumer Reports website where I took all the values except for the 85D which is from my door sticker).

    Vehicle
    Max Load (lbs)
    Tesla Model S 85D (2015)
    926
    Mercedes Benz S550 (2015)
    915
    Lexus LS 460L
    825
    Tesla Model S P85D (2015)
    920
    Porsche Panamera S (2015)
    1,080
    Infiniti Q70 (V6 or Hybrid) (2105)
    860
    BMW 535i (2011 newest year listed)
    1,060
    Cadillac CTS (2104 newest year listed)
    890
    Masserati Ghibli S Q4 (2014 newest year listed)
    925
    P85D beats all but 3 and 85D beats all but 2. Seems like a pretty typical max load to me.
     
  3. cwerdna

    cwerdna Active Member

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    #3 cwerdna, May 3, 2015
    Last edited: May 3, 2015
  4. David99

    David99 Active Member

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    I definitely exceeded the maximum load by a good bit once on a 2k mile road trip. Zero issues, never felt the car behaved differently. Still very stable, firm and smooth. Don't worry, the car can take a lot more. It's like the speed limit on roads. It's a limit that was set to be on the safe side at all times. It is not the maximum the car can handle.
     
  5. Just a Reader

    Just a Reader Member

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    Yes, it's likely that exceeding the maximum load doesn't cause practical problems. It may cause legal problems if you are involved in an accident, though.

    With the exception of the Panamera and the 535i I do find all figures to be on the low side for a full sized luxury 5-seater. The maximum load of the Lexus LS has never been anything else than ridiculous.
    I'm surprised, though. Mercedes' German website lists the maximum load of the S500 (S550 in the US) as between 665 and 715 kg (1466 - 1576 lbs.), depending on version.
    Those are also the figures you find e.g. on Edmunds' website for the US version: 2014 Mercedes-Benz S-Class Features Specs | Edmunds
     
  6. David99

    David99 Active Member

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    Many years ago Mercedes came out with a new S class that was so large and heavy, that when equipped with certain options, the max load was down to less than 4 adults. It was a huge embarrassment and went through the press. They did some adjustments and fixed it but they learned their lesson.
     
  7. ThosEM

    ThosEM Space Weatherman

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    This is a criticism that is frequently leveled against hybrids, e.g. the Lexus RX 400h. Now that breser has shown the real comparison, it doesn't hold much water and appears to reflect bias against vehicles carrying batteries or with soft springs. Now if you compare with a real truck like a Dodge Durango or a Chevy Traverse, expect ~50% more carrying capability.

    Consumer Reports: SUVs don't carry their weight - tribunedigital-chicagotribune
    Car Packing | How to Pack a Car for a Safe Road Trip - Consumer Reports
     
  8. gordo

    gordo Member

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    So basically this reads like a CYA on the part of tire manufacturers. There's no way Tesla or any of the other manufacturers would build vehicles where the seats and trunk space can't be fully utilized. Tire manufacturers are probably trying to gain some leverage against blowout lawsuits where some idiot grossly overfills the car and drives with the tires inflated 15psi below spec.
     
  9. skilly

    skilly Member

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    max load is also tied to tires - this warning seems to be directly related to the tire load specs. In fact, the factory tire load may be the weak point in the rating. This is why you see (mostly) parity with the other cars in the list one of the posters put up.
     
  10. scottm

    scottm Active Member

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    Is max load tied to EPA ratings, like tire pressure is?

    Anything to eek out a few more eMPG-equivalents... on the sales material.
     
  11. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Max load it tied to axle ratings (includes suspension, tires, wheels, and any other load bearing component such as bearings).
     
  12. breser

    breser AutoPilot Nostradamus

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    Like I said I pulled them straight off Consumer Report's site. I'd link directly there but you have to be a member to see these details. So here's a screenshot of the S550 entry:

    Screen Shot 2015-05-04 at 6.34.23 PM.png

    I looked for the information on Mercedes US website and couldn't find it. Not even the downloadable PDF displays it.

    You're certainly right that Edmuds is showing 1576 pounds. However, I'll point out that very prominent disclaimer.

    Screen Shot 2015-05-04 at 6.34.43 PM.png

    What I can say about Consumer Reports is whatever they publish is whatever the car they tested had. So I can't really explain the discprency.

    But I can assure you I wasn't cherry picking. I just searched for cars that came to mind as in the same class and added some of the suggestions that Consumer Reports had. I went to Consumer Reports because I knew I could find the info in a consistent manner across a variety of vehicles rather than having to dig on every manufacturers website.
     
  13. AudubonB

    AudubonB Mild-mannered Moderator Lord Vetinari*

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    Every tire manufactured - including those on our Model Ss - has a Max Load # stamped on the tire itself. So even though the placard in the OP suggests that limit is a function of the tires, not only is that not the case but it cannot be the case: if you put different shoes on the car there is the likelihood the tires' max load will be different.

    Rather, the datum is a function of what Jerry33 wrote in post #11 - all sorts of things.

    I don't have my car in front of me, but someone can go out to his/her car and read the tire datum directly from the sidewall and report back on this thread what that partcular # (times 4 tires, of course) is, and then we can compare that to what is on the placard.
     
  14. breser

    breser AutoPilot Nostradamus

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    Ask and you shall receive. 1653 lbs per tire.

    IMG_20150504_184635.jpg

    GVWR is 5280 pounds. GAWR for Front Axel is 2813 lbs and Rear Alex is 3307 lbs. So at GAWR the front axel is putting 1406.5 lbs of load on each tire and 1653.5 lbs of load per tire.

    I'm assuming that the max load on the tire placard is consistent with the load information on the other placard (sorry no picture of that placard). I don't remember what the curb weight said on my title to double check.

    Based on these assumptions and this data, it is indeed the tires that are the limiting factor. Though you can't be sure if other parts don't have similar limits.
     
  15. sorka

    sorka Active Member

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    The max load on my P85D says 889 lbs which I didn't realize until I just looked at that. Will easily exceed that with 4 adults and some luggage or 5 adults and no luggage.
     
  16. breser

    breser AutoPilot Nostradamus

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    What does fully utilized mean? Fill the entire volume with blocks of Uranium (heaviest natural element)? Or filled with a balloon of Hydrogen (lightest element)? The weight limit is necessary because building a car to be able to carry the entire cargo area filled with Uranium is not economical.
     
  17. breser

    breser AutoPilot Nostradamus

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    Just an FYI my chart is a bit off, especially in the years. The P85D row is actually a standard Model S. I believed the links when I clicked on them but now notice that the actual tested vehicle was often different and older. It doesn't significantly change the point but the chart isn't as accurate as it should be. My apologies for not being more careful. I'd edit it to fix but it's been too long.
     
  18. bwa

    bwa Member

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    #18 bwa, May 4, 2015
    Last edited: May 4, 2015
    I can't speak for Mercedes and Tesla, and these observations are according to feel and anecdotal, but I paid close attention: I had a few junker Volvo's, a VW Jetta, and a Honda Civic, that I used to strap as much lumber and construction materials as I could fit on top (with straps that were specified for many times the weight, although only routed and tightened appropriately) without rubbing the tires pulling out of the hardware store, often with as many sacks of concrete inside as it could take, distributed evenly. (Yes, the Volvo's won the competition, but that's not at all my point.) My point is that I noticed over time that certain particularly heavy loads that did not make the tires themselves pop or rub anything nonetheless did cause normal handling of the vehicle unladen change before and after the heavily laden trip to the point where I am convinced the car was damaged by the amount of load. However, across multiple vehicles and load amounts, I also noticed that this point of excess was directly related to how long it was loaded, and how hard it was handled along its courses, AND MOST importantly I THINK (not sure here) it also had a steep curve of damage that was SOMEWHERE BETWEEN the max loading specification of the vehicle on the placard and the point at which the tires started rubbing, that if I stayed under this steep part of the curve, then the damage did not accrue quickly. Once I learned this point, I did some suspension and axle repairs, and got immensely more cargo tonnage throughput with almost zero problems, except the eventual breakdown of the transmissions.

    In my opinion and experience, overall, vehicles not designed to carry more weight than specified WILL SUFFER WITH EXCESS WEIGHT. The key question is WHAT ARE THE ENGINEERING SPECIFICATIONS for what its maximum would be given very slight enhancements, and WHAT ARE those precise enhancements? I think there are so MANY evenly balanced parts with respect to weight capacity that that question most likely should be answered by well integrated engineers specific to the task of answering that question. I'm not saying that it's an intractable question, only that it's quite a thing to presume any particular answer or set of answers without expensive knowledge. That's just my very limited opinion and experience.

    Having said that, it would be fun to see the numbers output of what parts would need to be modified and what those particular modifications would do with respect to capacity, after such extensive engineering. OTOH, that's what heavy cargo vehicles are for. I actually had dreams of using Tesla parts for a truck until I realized trucks have so many efficiency improvements over cars for heavy cargo that the existing companies already outfitting trucks with EV would probably be better suited to that task. There went my dreams.

    Speaking of which, heavy is not always better. Garbage trucks ruin residential streets 4x faster than they should be ruined. Instead, a heavy semi-truck-with-trailer that parked in one spot per zone on one major heavy weight road with a bunch of automated car-weight robot cars that individually went down small areas (say, one half block each trip per car) to collect a smaller net weight of cargo (refuse) on each smaller car, which then returned to the mother ship to reintegrate the results (refuse) into the larger weight vehicle, would reduce the miles*weight on residential streets, greatly reducing wear and tear, as well as noise. This is exactly one idea I had for Tesla-type cargo carriage once the autonomous driving methods worked, but the robotic arm to collect the "cans" would need to be a light-weight one unlike the very heavy ones on regular garbage trucks. Take off the human-occupant part of a Tesla, and the resulting weight limits of even a car would probably be exactly the right amount for this type of distributed collection system. Even with the increased cost of complexity and parts, the savings on roadways alone would probably be way more than enough to offset the capital for that cargo system. I haven't done the calculations recently so I don't know if it's actually true, but it seemed like a big savings when I researched the numbers a year ago on this topic.
     
  19. scanred_x

    scanred_x Member

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    It could be an opportunity to reflect on the positive not only good choice we made to buy a green car that does not pollute, but also to think about the improvement of ourselves. The core issue of weight is to respect the maximum weight for active and passive safety, and try ourselves to lose weight and fit into a weight average more fair, equitable and respectful of the health and quality of life. For further information, consider that "metabolic syndrome" is the leading cause of heart attacks and strokes in the Western World...
    Green cars and ecological life: eat less, walk more, play sports, attention to quality and food, more fruits and vegetables, less meat and sandwiches...
     

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