Rough Ride with Winter Tires?

[filipwil]

Hi all,

First post here, thanks in advance for any guidance you can provide!

Bought a used Model S in April (2018 P100D). Since I'm in Michigan, I decided to get a winter tire setup, so this is my first year running them. I bought the 19" winter wheel/tire setup directly from Tesla but put them on the vehicle myself.

Ever since I swapped them in, I've noticed the ride is very rough. It isn't vibrating like it would if the wheels are out of balance (I actually just had that checked, just in case), but I feel every single bump in the road. It gets very uncomfortable.

I've tried playing with the tire pressure - Tesla says 42 psi on my summer tires. I think that's too high for my winter tires...I did some math based on some charts and got 35 psi to get the same load capacity, so that's what I'm running now. I'm not sure what I did is correct, though, so curious what I should be running them at. Regardless, it didn't make a big difference.

If it isn't tire pressure, what else could it be? Could the tires just be "harder" than the performance tires, regardless of pressure? If so, then I would think I'll always have a rougher ride on my winter tires. I can live with that if that's the case - not much I can do.

Could it be suspension related? The vehicle has air suspension...not sure how to evaluate it to see if it could be causing the ride issues.

The obvious answer would be to take it to Tesla for a service appointment, but that is very inconvenient for me since there isn't one close, so trying to understand if there is even something to be concerned with.

Thanks in advance!
Bill

 

[filipwil]

Anyone have any thoughts?

 

[Ostrichsak]

No math. 45psi. Running unsafe tire pressures on the roads isn't the solution to ride comfort.

Keep in mind that true winter tires have one thing at the top of the list: winter performance. Things like road noise, tire wear, comfort, handling, etc. all take a back seat to the desire to have the best winter performance possible. The compounds used for this purpose are entirely different because they must remain pliable to very cold temperatures. Performance tires become hard as a rock at these temps and it's like marbles on glass for traction. This is bad.

This is also why I choose to run something like a Continental Extreme Contact DWS 06+ year 'round.

I realize that I sacrifice a tad in summer performance over an ultra high performance summer tire. I also sacrifice a tad in winter grip and traction over a dedicated winter/snow tire. The sacrifices on the margins are worth it for me because I get a great tire in all conditions even if not the best possible at the extreme edges but I don't have to change out wheels/tires twice a year the way some do.

That's just me though. No matter what you do, 45 psi is the proper pressure and it has little to do with the tires and is why the manufacturer of the vehicle is responsible for proper inflation numbers. A Tesla Model S is a heavy pig and should have much higher tire pressures than a 3,500lb 4-dr sedan. Simple physics.

 

[filipwil]

Thank you Ostrichsak! Extremely helpful!

Just trying to learn more on this, since I've spent so much time thinking about it: wouldn't the recommended pressure depend on the tires used? I didn't reduce pressure just for ride comfort - when it was uncomfortable, I started thinking the pressure on the door sticker was probably not correct for the winter tires. So I tried to do some research and convinced myself after some math that the right pressure was 35 psi.

My understanding is each tire has a load capacity that varies based on pressure, which the load index represents. So all I need to do is make sure I meet or exceed the load capacity of my summer tires. I did that math, and I can do that with my new tires at 35 psi. Anything higher is "overkill."

Am I misunderstanding how this works?

Thanks again for your help, sounds like my ride difference is probably just the tires, regardless of pressure.

-Bill

 

[Ostrichsak]

Thank you Ostrichsak! Extremely helpful!

Just trying to learn more on this, since I've spent so much time thinking about it: wouldn't the recommended pressure depend on the tires used? I didn't reduce pressure just for ride comfort - when it was uncomfortable, I started thinking the pressure on the door sticker was probably not correct for the winter tires. So I tried to do some research and convinced myself after some math that the right pressure was 35 psi.

My understanding is each tire has a load capacity that varies based on pressure, which the load index represents. So all I need to do is make sure I meet or exceed the load capacity of my summer tires. I did that math, and I can do that with my new tires at 35 psi. Anything higher is "overkill."

Am I misunderstanding how this works?

Thanks again for your help, sounds like my ride difference is probably just the tires, regardless of pressure.

-Bill

Tire load is simply pass or fail. Either the tire is engineered to handle the load of your vehicle's requirements or it isn't. You don't alter your tire pressure based on your tire's load. The proper tire pressure is what is printed on the manufacturer's label on the inside of your car's door frame.

 

[Doanster1]

Most likely it is your 35psi setting as previously stated. Winter tires use a softer compound, not harder, so that they don’t become hockey pucks in the cold. Which tire are we taking about?
Gonna swap my 19” Hakkas on this weekend as we’re supposed to have a white xmas and following couple days.

 

[filipwil]

PIRELLI WINTER SOTTOZERO 3, which I believe is what Tesla sells on their winter tire setup (they couldn't procure the tires so I bought them myself). I was initially running at 43 psi, went down to 35 psi after noticing the rough Ride and convincing myself (sounds like incorrectly) that the pressure should be lower for those tires.

 

[Needsdecaf]

Tire load is simply pass or fail. Either the tire is engineered to handle the load of your vehicle's requirements or it isn't. You don't alter your tire pressure based on your tire's load. The proper tire pressure is what is printed on the manufacturer's label on the inside of your car's door frame.

Sorry, but you are misinformed on this one.

Tire loading is a function of both weight and speed. Based on your driving conditions, and your vehicle load, it is 100% permissible to alter your tire pressure to suit your use case. The sticker on the door is for MAX loading conditions (i.e. at the GVWR of the vehicle). But many vehicles, mostly European, have alternative pressures listed in the manual, for various conditions. Some luggage, no passengers. More passengers, more luggage, and max load.

This is an older chart for the first generation Cayenne, but it's straight out of the Porsche owner's manual. Note that for a base Cayenne, there is a partially loaded pressure, a comfort partially loaded pressure, and a fully loaded pressure. My 911 also has pressures recommended if you are doing sustained high speed running, like on the autobahn. My Cayenne, which has TPMS, actually has this built in, where you can select your loading condition and comfort level, so it knows not to alert you if you're running, for instance, the unloaded, comfort pressure.

I have seen similar charts in my BMW and Lexus as well.

So, definitely NOT pass / fail, one size fits all.

BTW, I like your choice of DWS 06's. I've owned them on multiple cars, in multiple generations and they are an excellent tire. We run them on our Cayenne right now and I run slightly above the 3 passenger / comfort pressure recommended for that tire size, as we either have 1, 2 or 4 people and very little luggage. When we load up, I always air up before the trip. Tire wear has been dead even over the 105k miles we've owned it.

 

[Ostrichsak]

Sorry, but you are misinformed on this one.

Tire loading is a function of both weight and speed. Based on your driving conditions, and your vehicle load, it is 100% permissible to alter your tire pressure to suit your use case. The sticker on the door is for MAX loading conditions (i.e. at the GVWR of the vehicle). But many vehicles, mostly European, have alternative pressures listed in the manual, for various conditions. Some luggage, no passengers. More passengers, more luggage, and max load.

This is an older chart for the first generation Cayenne, but it's straight out of the Porsche owner's manual. Note that for a base Cayenne, there is a partially loaded pressure, a comfort partially loaded pressure, and a fully loaded pressure. My 911 also has pressures recommended if you are doing sustained high speed running, like on the autobahn. My Cayenne, which has TPMS, actually has this built in, where you can select your loading condition and comfort level, so it knows not to alert you if you're running, for instance, the unloaded, comfort pressure.

I have seen similar charts in my BMW and Lexus as well.

So, definitely NOT pass / fail, one size fits all.

BTW, I like your choice of DWS 06's. I've owned them on multiple cars, in multiple generations and they are an excellent tire. We run them on our Cayenne right now and I run slightly above the 3 passenger / comfort pressure recommended for that tire size, as we either have 1, 2 or 4 people and very little luggage. When we load up, I always air up before the trip. Tire wear has been dead even over the 105k miles we've owned it.

Your situations are outlier instances and NOT factory recommended for normal public road use which is what this conversation is about. Tire selection in terms of load is absolutely pass/fail for your situation and in this case the situation is standard use. Selecting a tire that doesn't meet load requirements for this (or any) application is ill advised. You said I'm misinformed and then went on to expand on & confirm basically what I just said. Summarize for me where I'm misinformed in as few words as possible.

 

[cityhpper]

The Sottozero 3 is a winter tyre made for performance cars, and for sustained high-speed driving i.e. like crossing Germany during the winter months. It is on the stiff side when it comes to side-wall and rubber compound, compared to tires like Nokian Hakka 3 and Continental Viking Contact 7. But it should not make the car feel very rough or uncomfortable. I had a 2018 MS 75D Loaner for two weeks last winter, which had the Sottozero 3 mounted. Ride was firm but not close to rought or uncomfortable.

Cycle the air suspension of your car through all hight-levels. Then return it to normal hight and comfort mode. See if this changes anything about how the car rides.

Make sure to run at least 45 PSI for these tires, as recommended above. Leave the car sitting in your driveway for the night and check the pressure next morning, to make sure the tires have ambient temperature. Personally, I run my 245/45R19 tires at 47-48 PSI in the cold months.

 

[Needsdecaf]

Your situations are outlier instances and NOT factory recommended for normal public road use which is what this conversation is about. Tire selection in terms of load is absolutely pass/fail for your situation and in this case the situation is standard use. Selecting a tire that doesn't meet load requirements for this (or any) application is ill advised. You said I'm misinformed and then went on to expand on & confirm basically what I just said. Summarize for me where I'm misinformed in as few words as possible.

Uh, those are FACTORY recommendations that are printed in the FACTORY manual regarding air pressure vs. load.

Is that few enough words?

I never, ever, said anything about selecting a tire which didn't meet load requirements. In that, you are completely correct. If a car requires a certain load rating, you need to buy a tire that meets that load rating. However, your statement said:

You don't alter your tire pressure based on your tire's load. The proper tire pressure is what is printed on the manufacturer's label on the inside of your car's door frame.

And I literally provided you a FACTORY recommended use case where you can, absolutely, alter your air pressure based on load. The table, which is provided by Porsche in their owner's manual supplied with the vehicle, clearly states that under "Partially loaded (up to 3 people and 46 pounds of luggage)" conditions, you may run as low as 35/39 psi depending on size and type of tire (summer vs. all season). But that in "Fully loaded (more than 3 people and 46 pounds of luggage)" conditions, you need to run more air pressure.

Those are not outlier instances. And they are 100% factory recommended for normal public road use.

 

[Midnightsun]

Tire pressure is not rocket science. The heavier the car the more pressure required and therefor why we see these high pressures on Teslas. Bottom line is a Tesla is a darn heavy car!

All one is trying to accomplish is to maintain a certain shape where tread wear/contact is at its optimal. Most German manufactures have it right with loaded and unloaded pressure recommendations as those would be optimal in both cases.

Take the same tire brand size and put it on a standard weight car, the recommended pressure will most likely be about 10psi less. Put 42 psi into it on a "normal" weight car and you will be riding on the centre portion of the tire.

You will wear those winters out in no time at 35psi with typical a under inflated wear pattern happening. Adjusting them down a few psi is fine but not 10. Wear Patterns

Still do not understand why you are seeing a harsh ride on winters. I have been driving on dedicated winters for probably 40 years and change cars maximum every 3 years. I all that time with so many cars and different brands of tires I have always experience a softer ride albeit always louder simply due to tread design on winters. Maybe a placebo affect like someone who puts a loud exhaust system and swears it is much faster.

 

[Alan2000]

Sorry, but you are misinformed on this one.

Tire loading is a function of both weight and speed. Based on your driving conditions, and your vehicle load, it is 100% permissible to alter your tire pressure to suit your use case. The sticker on the door is for MAX loading conditions (i.e. at the GVWR of the vehicle). But many vehicles, mostly European, have alternative pressures listed in the manual, for various conditions. Some luggage, no passengers. More passengers, more luggage, and max load.

This is an older chart for the first generation Cayenne, but it's straight out of the Porsche owner's manual. Note that for a base Cayenne, there is a partially loaded pressure, a comfort partially loaded pressure, and a fully loaded pressure. My 911 also has pressures recommended if you are doing sustained high speed running, like on the autobahn. My Cayenne, which has TPMS, actually has this built in, where you can select your loading condition and comfort level, so it knows not to alert you if you're running, for instance, the unloaded, comfort pressure.

I have seen similar charts in my BMW and Lexus as well.

So, definitely NOT pass / fail, one size fits all.

BTW, I like your choice of DWS 06's. I've owned them on multiple cars, in multiple generations and they are an excellent tire. We run them on our Cayenne right now and I run slightly above the 3 passenger / comfort pressure recommended for that tire size, as we either have 1, 2 or 4 people and very little luggage. When we load up, I always air up before the trip. Tire wear has been dead even over the 105k miles we've owned it.

A family member just rolled their '22 Model S Plaid on a mountain road after losing traction in cold weather conditions. They are ok but car is a total. I have been planning to switch to performance all season tires and that was the final push to do so. Most people unless on a track will not derive any benefit over performance AS tires, but 100% of them will increase their likelihood of having an accident in wet or cold weather conditions, and go through tires a lot faster. The two tires I picked for my 22 Model S are the DWS 6 and the Michelin Pilot Sport All Season 4. I think the DWS have slightly better specs and tire wear, along with being less expensive compared to the AS4 but unfortunately they don't come in my size for 19" rims. So I was toying with the idea of going -1 in size with the DWS or going with the AS4. Any thoughts on -1 for front and rear? Giving up .39" in width. Cost is not a big factor but I think the DWS are quieter so that is pushing me to DWS but not sure about going 1 size smaller.

I think Tesla may overstate inflation pressure for range ratings or maybe just being lazy to specify the PSI range as do some other manufacturers for load and speed conditions. 41 for S seems a bit high unless you have the car heavily loaded car or plan driving at triple digit speeds for an extended period of time, which likely is not the case in the USA. While the S is heavy, it's about the same weight as luxury ICE cars such as S Class MB. Have seen comparable weight vehicles to the S with lower PSI ratings. What I don't know is if the higher torque of the S can play a factor of Tesla setting what appears to PSI recommendation on the higher side.