Tire Pressure - Comfort and wear

Due to the excessive rear camber on the MYP, if I under inflate then the inside of the tires wear out far too fast.

ASS refuses to function when tire pressures are this low. I found out the hard way when I summoned the car and it pulled out of a parking spot and immediately stopped in front of several other cars that wanted to pull out but were now blocked.

good point on that, and unfortunately rear camber is non adjustable. I can't picture how tire pressure speeds or slows the inside shoulder wear, but perhaps there is an explanation on that.

that is good to note, I haven't used ASS for a while, but thanks for sharing a data point. not fun to have ASS stuck in the middle of costco lot.

it REALLY depends on the tires you have. For example the OEM procontact RX if you run them below 36 for any period of time the edges go baldand they are much louder on the road (but ride better) in no time they need 38-42. The ion evos will do okay down to 35 without excess wear but I dont find that its worth the extra small bit of comfort to deal with a tire light on a cold day. After multiple model Y and tires since 2020 I just go between 40-42 anyway it's the best middle ground that makes sense without introducing a sound or wear issue if you have a solid alignment. There could be outlying cases based on spec or model of tire to be seen but to me after all I tried out to see if I could break the mold in the end nothing was worth it. Comfort outside of juniper needs a suspension change and if you want even more then going down to 18s but thats a whole other can of worms.

🧐

Interesting. At first I was debating to go to 255/50 for that extra 1" sidewall, or even going to 18" to make a total of 2" more sidewall. 42 PSI seems off to me so I did in depth learning of tire loads and how it impact handling, wear, and comfort (and blowout risk). Stuck with this 32/35 psi for a while and don't crave for any increase in comfort, so stuck with the ProContact RX from Tesla. Haven't noticed increased sound in highway over the past 10k miles, but could potentially start to show more once any sign of uneven wear shows. If any, highway ride felt noticeably quieter, which is counterintuitive from the 'common knowledge' of high pressure = less road noise. I speculate the 42 PSI is just for EPA to get max test. If they recommend 35 psi all around, they can potentially lose 10+ miles of range quoted.

I would speculate the same. The ride is very obviously harder at 42 psi as well. I should also note the majority of my testing on the RX Tires was with the T2 version. I didn't have a noticeable increase in sound until the Tires got down to 5-6/32, It seemed a little louder but I never really thought about it and then I aired up to 42 after maybe eight months of 34-36 and couldn't believe how much quieter it was or how much worse it rode lol. I also tried out 255/50 on the 19 inch Gemini wheels using Pirelli scorpion zero AS plus 3 elect pncs but found barely any change at all so actually swapped those tires out within the 30 day period at discount tire for the normal non elect non zero version Pirelli scorpion as plus 3 in the same 255/50 size and found those much more comfortable and quiet (minus some pinging over big bumps on the interstate). In the end though on that vehicle I ended up going down to 18 inch aftermarket wheels and running 255/55 tires (the same scorpion as plus 3 actually and this size doesnt ping over bumps somehow) and never looked back. I also messed with tien struts before just going for full comfort coilovers.

Appreciate the share! Be prepared for future DM on questions about the comfort coilover haha. Is it by any chance MountainPass non adjustable ones?

Not fun to have ASS stuck anywhere, really.

Don't know if this helps your data points, but in my experience of mostly highway driving and 12000 miles since new on OEM tires at 42psi, tire wear appears minimal. AWD and not mashing the gas. I may drop down to 40 to assist with comfort, although my car is always heavily loaded with clothing, tools, etc.

It’s my first car with low-profile tires, so I’m not going to risk denting a rim with the low pressures you’re running. I am comfortable with a 2-3psi reduction, but that’s about it. With tire technology as it is, tire design, materials and construction (and wear) will always make the biggest difference. Unless, you go way outside the recommended pressure like you have! Hahaha. BTW, a high tire pressure does not automatically guarantee higher efficiency. In fact, it can have the opposite effect if the road surface is rough. There’s a sweet spot with any tire between efficiency, comfort and traction. If you’re hell-bent on getting a more comfortable ride out of your tires, a high-quality touring tire with a larger aspect ratio on smaller rims is the way to go.

I installed camber adjusters myself in about an hour total for both rears. Very simple. I suggest the Unplugged Performance camber arms for the way they adjust and tighten down.

How do you keep the low pressure warning from signaling?

I do not. It’ll keep warning you under 36 psi. Hard warning (red triangle) starts at 26 psi and being more persistent. As long as you are above 26 psi, no warning chime, just low pressure yellow light. I was used to heavily tuned car on my younger days, so no issue with yellow warning for me personally.

Are you sure it didn’t just move out of range? Why would it start then stop?

No, it was headed towards me. Also more importantly, an onscreen alert confirmed ASS was disabled due to low tire pressure.