For the P zero Elect max summer tires?
That would be unacceptable to me. Driving plaid in low temps is already painful as is. Its a total different beast in warm temps with traction.
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Plaid 21” rear tire woes - factory defect?
- Thread starter KOL2000
- Start date
That would be unacceptable to me. Driving plaid in low temps is already painful as is. Its a total different beast in warm temps with traction.
No, I'm using some NA0 porsche spec goodyear F1. They were track takeoffs I bought from a guy with a 911 - they're not designed for such a heavy car like a model s. I bought two sets from the dude for $600 total I think it was. Figured they were so cheap it would be worth a test.
If you get those pirellis, get the NF0 ones, those are designed for a taycan. The NA0 & NA1 are designed for the 911's.
MFrunkerOG
Active Member
Here’s some data that may interest you people.
The 19” Tesla oem tires are a load rating of 104F / 107R. The 21” Tesla tires are at 101F / 102R
The rear lamination problem is on the 21”, not the 19”. Now some of us who have 20” wheels also don’t have the same problem because our (my) tires are load rated at 104F/105R.
Now everyone remember that the load rating is listed is the max for that tire at 50psi (XL tires) and goes down per psi reduction . For example, the 1874lbs load rating of the 295 oem rears on a 21” wheel is at 50psi. For each psi lower than 50psi, the corresponding load capacity reduction is 1874/50=37.5 lbs. At 42psi, your 295 rear tire load capacity is reduced by about 300lbs, down to 1574 lbs.
Onto the car now. When you accelerate, the load bias of the car shifts to the back due to the G force applied. So your rear suddenly becomes much heavier than what it was at rest.
Fast forward this thinking - your load rating of 102 in the rear is likely the problem as it is placing far too much stress on the tire that is down to 1574lbs in the load capacity at 42psi. The car weighs 5000 lbs with driver. That is 1250 lbs per corner at rest. At 1 G force, make that 2500lbs per corner (a bit fuzzy math here but you get my point)
Now if you move up to a 305 tire on the 21s, that takes the load rating up from 102 to 104. And I don’t think there is a big diameter increase / any fitment problem. Ya’ll see what I’m saying here?
Someone at TESLA MAY NOT HAVE DONE g force load calculations before they decided on a 102 load rating for the 21”rears! OR, maybe they did do it, but wanted to squeeze in that extra mile range with a smaller tread patch at the cost of load rating!
The 19” Tesla oem tires are a load rating of 104F / 107R. The 21” Tesla tires are at 101F / 102R
The rear lamination problem is on the 21”, not the 19”. Now some of us who have 20” wheels also don’t have the same problem because our (my) tires are load rated at 104F/105R.
Now everyone remember that the load rating is listed is the max for that tire at 50psi (XL tires) and goes down per psi reduction . For example, the 1874lbs load rating of the 295 oem rears on a 21” wheel is at 50psi. For each psi lower than 50psi, the corresponding load capacity reduction is 1874/50=37.5 lbs. At 42psi, your 295 rear tire load capacity is reduced by about 300lbs, down to 1574 lbs.
Onto the car now. When you accelerate, the load bias of the car shifts to the back due to the G force applied. So your rear suddenly becomes much heavier than what it was at rest.
Fast forward this thinking - your load rating of 102 in the rear is likely the problem as it is placing far too much stress on the tire that is down to 1574lbs in the load capacity at 42psi. The car weighs 5000 lbs with driver. That is 1250 lbs per corner at rest. At 1 G force, make that 2500lbs per corner (a bit fuzzy math here but you get my point)
Now if you move up to a 305 tire on the 21s, that takes the load rating up from 102 to 104. And I don’t think there is a big diameter increase / any fitment problem. Ya’ll see what I’m saying here?
Someone at TESLA MAY NOT HAVE DONE g force load calculations before they decided on a 102 load rating for the 21”rears! OR, maybe they did do it, but wanted to squeeze in that extra mile range with a smaller tread patch at the cost of load rating!
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Thanks for the pics. With your tires it looks like there's no damage/wear on the inside edge (yet?) so perhaps it's a specific Michelin tire plant issue, or manufacturing variance issue, which has had so many other Micheline 21" tires coming apart.
The safety component is huge. The Michelin 21" tire has become structurally compromised for many owners in a nearly impossible to see area--the inner sidewall. (See dozens of photographs on this thread, and those are a tiny subset of the total failures that happen to be posted on a TMC Forum. There are likely a far larger number of failures not reported here--note the massive, months-long wait for replacement tires as just one indicator.)
The MS and MS Plaid can reach speeds upwards of 150 mph where a catastrophic tire failure might occur with fatal results . . . and because no one has yet died or been injured is NOT a reason to delay the recall of these tires. Do we need to really need to recreate the Firestone fiasco before action is taken? This was a stunning failure on so many levels, with many lives lost and billions in financial impact; this is a powerful example of what can go wrong:
Absent some change, with ever larger numbers of cumulative MS sales, plus time, these compromised tires will likely lead to major accidents, especially as these cars transition to 2nd and 3rd owners . . . .
Tesla is selling these in the EU/Germany now and we very much hope to not have stories of high speed accidents in a year or three, hence the interest in getting this tire issue addressed ASAP.
Also of note is that there has not been even one report of tread separation with the Pirelli 19" tire used in the same application . . . .
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The OEM spec tires are built differently, so no one can apply similar principles across all of the tires based on a load rating alone. This is why you see the same exact brand and size of tire have a weight variation as high as 2-3 pounds per tire depending on if it is OEM spec or open market design.
MFrunkerOG
Active Member
Hayseed_MS
Spreader of "Endless Non Sequitur"
Can you confirm they do have the foam in them? Pirelli does not list their NFO as having PNCS.
MFrunkerOG
Active Member
As others have said, anyone with the Michelin 21” PS4 tires, get them checked and if they have the issue, call Michelin’s warranty number and open a case. My left rear tire was losing pressure so I ordered two rears (12k miles on the car) from Discount Tire. I opened a case with Michelin, and had them installed yesterday. Today I was refunded 100% for both rear tires. The rep at Discount Tire said he’s never had a 100% warranty claim go through so easily. I went with the non acoustic tech tires since the T2s are on back order.
Did your 100% refund include the cost of installation/mounting, balance, taxes, etc.?
I ask as both of my rear tires are losing pressure (about 1 to 2+ psi per week now) and I have some mild "lathing" visible. I am being told that while Michelin will replace the tires (when they're back in stock--still on nationwide backorder, seemingly forever), but I have to pay for everything else . . . .
Would you mind sharing your case number so that we can use your case a precedent for others? Thanks!
I called the general 800 number that was suggested in this thread, 1-866-866-6605.
I called the general Michelin tire support number I found from Google: 1-866-866-6605. I followed the prompts to open a tire warranty case and spoke to a support rep.
Yep, I had to pay mounting, balancing and disposal fees. I'd rather not share a claim number that's tied to my personal info on a public forum. I'll be happy to answer any questions.
vberber
Member
God I hate These Rear cambers arms, 12k miles about 6 months worth of use, right on time when N2itive’s finally ships out the back ordered adjustable rear camber arms… another 2k down the drain coming up.
vberber
Member
Oh and forgot to mention tesla service just inspected my tires as courtesy last week, doubt it even gets put on a lift, they probably only check depth I’m assuming?
Wow, what a great picture of the Michelin 21" problem child tire failure. Please send this picture to Michelin ASAP (and the NHTSA as well), especially because your tire looks barely worn.
But I'm confused: this picture is with the original OEM/stock set up, or the new, n2itive 3rd party suspension control arms?
vberber
Member
Original OEM/ stock set up.
I have yet to receive the n2itive rear cambers arms but they just shipped them since they were back ordered since July when I placed my order.
That's not tire failure, you can clearly see the entire corner of the tire has been worn down through the tread into the belts.
n2mb_racing
Active Member
I haven't been following the thread. What's the issue? What should we be looking for? I have noticed a slow leak in one of my rear tires that I can't find the source of.
Look on the inside edge of the rear tires. they may be worn down to the belts.
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