Why 42 PSI ?

[ODWms]

I've been running 50 psi since the beginning (2018), and I can confirm no issues with tire wear or anything else. My first set lasted more than 50k miles. Second set are at 39k, and counting. I fully expect to go over 50k again.

 

[legendsk]

Because 42 is the answer to life, the universe and everything else.

 

[Willy’sEV]

I've been running 50 psi since the beginning (2018), and I can confirm no issues with tire wear or anything else. My first set lasted more than 50k miles. Second set are at 39k, and counting. I fully expect to go over 50k again.

You must never exceed 10mph with that kinds of tire wear.

 

[texas_star_TM3]

You must never exceed 10mph with that kinds of tire wear.

No kidding. No way the oem tires are still legal after 50k miles…. If you are lucky you’ll get maybe 35k miles tops. No way over 50k

 

[DrChaos]

I've been running 50 psi since the beginning (2018), and I can confirm no issues with tire wear or anything else. My first set lasted more than 50k miles. Second set are at 39k, and counting. I fully expect to go over 50k again.

50k on 20" Pilot Sport 4S?

that's really difficult to believe.

 

[kpanda17]

Michelins are amazing

 

[wws]

My 2018 came with the original "T0" spec MXM4s, and I now have the newer "T1" spec. The originals barely lasted 30k miles. The current ones have 45k on them, and only now starting to look like they will need to be replaced soon. I've tried to keep ~42 psi cold since new.

 

[ODWms]

Yep. I'm on my second set, that are right about 39k miles. I have no reason to suspect they won't last to 50.

 

[Willy’sEV]

My 2018 came with the original "T0" spec MXM4s, and I now have the newer "T1" spec. The originals barely lasted 30k miles. The current ones have 45k on them, and only now starting to look like they will need to be replaced soon. I've tried to keep ~42 psi cold since new.

Did not know there was a change.
I bought new MXM4’s a few months ago from the Tesla service center.
How do you tell if you have the TO or T1?

EDIT: I just looked at my tires and I see the T1 in the circle!

So what is difference between the T1 and T0?

 

[Kevy Baby]

So what is difference between the T1 and T0?

Google search gave me an answer right here on TMC:

T0 means it’s been designed to the specs set out by the original manufacturer for use on the car. T is Tesla and 0 is the first revision. T1 would be more modern design etc. Sometimes keeping a T0 on an older Tesla would be the right thing to do for the age rather than just going for the newest T revision.

 

[holmgang]

8 pages of speculation on why a manufacturer might recommend something. does it matter? use it as one reference, but set your optimal pressure based on your preferences and observation of wear, responsiveness, comfort, etc

my previous bmw came in multiple OEM sizes, and the suggested pressure on door jamb varied on sizes, vehicle load (5pax, 2pax, etc), and whether user favored "ECO" or etc. it was a big pressure matrix.

 

[404 Not Found]

I just got a new Model Y Standard Range. It has 19" Pirelli Scorpions. I find the ride way too harsh on even the smallest road imperfections, especially in my city where there has been zero road maintenance for 30 years. I figure the 42 psi number was chosen for EPA range testing and is necessary for maximum loading. That means up to five fat people and luggage for all. Plus a trailer at 350 lbs tongue weight. Another factor is the max speed rating of 217 kph. I'm going to try out 38 psi. I can't see how that would be a problem with just my skinny wife and I tooling around at 110 kph or less.

 

[timk225]

Why 42? Easy, because Elon Musk is how he is, this question answers itself. Hitchhikers Guide To The Galaxy, 42, there's the answer.

 

[Kevy Baby]

Because 43 is too high and 41 is too low

 

[rpiotro]

I just got a new Model Y Standard Range. It has 19" Pirelli Scorpions. I find the ride way too harsh on even the smallest road imperfections, especially in my city where there has been zero road maintenance for 30 years. I figure the 42 psi number was chosen for EPA range testing and is necessary for maximum loading. That means up to five fat people and luggage for all. Plus a trailer at 350 lbs tongue weight. Another factor is the max speed rating of 217 kph. I'm going to try out 38 psi. I can't see how that would be a problem with just my skinny wife and I tooling around at 110 kph or less.

Any UHP tire in combination with a skinny sidewall is going to result in a rough ride. Not sure dropping the pressure to 38 will have much affect but try it.
Correct about low combined weight usually does Ok at lower pressures. My wife's SLK 130 (R172) has max recommended pressure on the door sticker but when you open the gas door there is a different set. Recommended pressures for both lightly loaded and heavily loaded. Because Germans.

 

[kpanda17]

Interesting for I have two Teslas and watching the rapid tire wear on one
so far not a fan of the M3 continental procontact, wearing too fast
big fan of the MYP Michelins PSAS4, wearing perfectly
i know there is a big difference in cost, thus performance and should be expected
just my observation as I now have a depth gauge
good news the wear is even across all eight tires, just too quick on the M3

btw, I run all eight at high psi, 45-47
No rough ride issues

 

[enemji]

 

[404 Not Found]

Any UHP tire in combination with a skinny sidewall is going to result in a rough ride. Not sure dropping the pressure to 38 will have much affect but try it.
Correct about low combined weight usually does Ok at lower pressures. My wife's SLK 130 (R172) has max recommended pressure on the door sticker but when you open the gas door there is a different set. Recommended pressures for both lightly loaded and heavily loaded. Because Germans.

I've had a few Mercedes cars and have seen the label that shows different tire pressures depending on the quantity of passengers and luggage on board. You also make a good point about the UHP tires. Perhaps I won't see any meaningful improvement by adjusting pressure with these tires. I am going to try 38psi on a rough road test and also on a smooth, flat highway. I will then raise the pressure 4 psi and repeat. I will also record the power consumption on both runs and report back.

 

[404 Not Found]

I did try out 38 psi today. The ride was still firm but the worst harshness was gone. No more minor rattles from road imperfections. Handling was still very good but not as responsive as before. I didn't test consumption, but it felt like it might degrade due to the tires working harder. It the end, I inflated them back to 42 psi, thinking it is best overall and then the sharper handling returned. You just have to pick your routes carefully and the ride will be fine. I think Tesla chose those pressures for good reason. The door jam sticker is usually right nowadays.

 

[rpiotro]

I did try out 38 psi today. The ride was still firm but the worst harshness was gone. No more minor rattles from road imperfections. Handling was still very good but not as responsive as before. I didn't test consumption, but it felt like it might degrade due to the tires working harder. It the end, I inflated them back to 42 psi, thinking it is best overall and then the sharper handling returned. You just have to pick your routes carefully and the ride will be fine. I think Tesla chose those pressures for good reason. The door jam sticker is usually right nowadays.

Funny that you mention picking routes for the best ride. I have been doing that for a couple years now as the roads around here further deteriorate. Yet taxes keep going up.