Model 3 Tire Pressure

[BYE FOSL]

I have 45 psi in my 20” tires, and the car is smoothe and soft compared to any car I have had since I got Grandpa’s Buick 48 years ago.

 

[Big1matt]

Test drove a performance version on 20" wheels few weeks ago(not sure what the PSI was in tires) and I was surprised how smooth it rode around town.

 

[chracatoa]

Interesting. Maybe the 20" wheels are better. I wonder if I can replace my 19" at some point.
I'll still have to try 39 psi. I'll should have an idea by the end of this week. Unfortunately, my good tire pressure gauge broke, and the other one is useless, so I'm getting a new one.

 

[GPinzone]

I got a scare this morning with a low tire pressure warning as soon as I got on the highway. It was like 36 psi. The temperature rose as I was driving and the warning turned off. Today was the first real cold morning since I got the car, so it's just air contracting, not a leak. I'll have to remember to top them all up to 42psi.

 

[anhnguyen]

...anyone getting low pressure issues? my front left was at 36 while the others were at 37-38..this morning they are all 37 and getting a low pressure setting on just the front left again..

 

[GPinzone]

...anyone getting low pressure issues? my front left was at 36 while the others were at 37-38..this morning they are all 37 and getting a low pressure setting on just the front left again..

Read the post before yours. Welcome to the fall.

 

[rsomrek]

Capacity to hold moisture is what is responsible for expansion beyond ideal gas law. A pure nitrogen fill significantly reduces gas expansion due to temperature.

-edit-
decided to post a source:
Nitrogen vs Air In Tires - Why Nitrogen in Tires

The moisture in air is a gas and so o\beys the universal gas law. It's a very small part and does not compare to the amount of nitrogen and oxygen that comprise ordinary air.

 

[follow.johnny]

My 19" Sport Wheels were exactly at 42 PSI when I took delivery. After having the car for 2 months and temperature drops in the night into the morning in California (On days that aren't 90-100+ degree) the tire pressure drops from anywhere from 36-39 PSI.

I get a few low tire pressure warnings, but the tires eventually warm up to 42 when driving and the warning goes away.

 

[StellarRat]

I drove around most of the summer at 42, but when the weather got colder one of my tires got down to 36 and the car started yelling at me. I filled them all up to 45 and I can't tell a difference other than the Bitching Betty is quiet now.

 

[Firedog7881]

Picked up mine on Sunday and they were at 49. I was surprised at the amount of road noise and dropped them to 46 and it was much quieter. I was cruising on the highway most of today and I’ve been averaging 238 Wh/m for the first 250 miles using Chill mode and Standard regen.

 

[zhu-]

I picked my car up last Friday with 45-48 psi. Dropped down to 41-42 and ride does feel a bit softer though tires feel slightly mushy around corners. I'm looking forward to when I can swap these out for some better performance all seasons.

 

[Vines]

I run 45 cold, and this translates into 49 or so when warm.

It might be slightly harder than the recommended 42 cold, but I was aiming to see what is the best mileage I can get.

If your tires are 42 when driving, then they are actually under inflated slightly, as the measurement should be taken from a cold morning.

 

[follow.johnny]

Just got air this weekend in all 4 tires on my 19" Sport Wheels at 42 PSI Cold (Tires: Continental ProContact RX)

They've been running cold at 36-38 PSI and constantly get low tire pressure and alert won't go away even when tires warm up (A reboot fixes the low pressure warning)

Went to America Tires to get free air with their digital pump system that displays current tire pressure and set your factory tire specs to inflate.

 

[ngogas]

Fall and winter is when everyone need to check their tire pressure and top it off. Just like the nagging fire alarm batteries. Pain in the butt but can save you life.

 

[EVnut]

Fall and winter is when everyone need to check their tire pressure and top it off. Just like the nagging fire alarm batteries. Pain in the butt but can save you life.

I dare say that tire pressure should be checked more often than 2x per year.... again for safety.

 

[DougInCT]

I picked my car up last Friday with 45-48 psi. Dropped down to 41-42 and ride does feel a bit softer though tires feel slightly mushy around corners. I'm looking forward to when I can swap these out for some better performance all seasons.

I used to tune my classic Corvette by changing the tire pressures. It had a stiff rear suspension, so depending on tire pressure, I could bias towards understeer or oversteer. Lots of fun testing on Angel's Crest Highway.

I was waiting for someone to note the cornering performance difference. I'd love to see some skid pad results!
Anyone playing with tire pressures, just be aware that it will absolutely impact how your car handles.

 

[Zidarich]

I can never get it exact when filling the tire pressure. Mine say 47psi. Anything wrong in terms of safety with running that high? Don’t know if overfilling by a small amount could be dangerous and if I should drop it lower.

 

[voip-ninja]

I can never get it exact when filling the tire pressure. Mine say 47psi. Anything wrong in terms of safety with running that high? Don’t know if overfilling by a small amount could be dangerous and if I should drop it lower.

The tires themselves list the maximum pressures which are likely a lot higher than 47 psi.

Overinflating can gain a little bit more efficiency but tends to negatively affect handling and comfort past a certain point.

 

[Vines]

I have run between 45-50 psi on mine. It gives slightly better efficency, but worse handling.

 

[TT97]

The tires themselves list the maximum pressures which are likely a lot higher than 47 psi.

Overinflating can gain a little bit more efficiency but tends to negatively affect handling and comfort past a certain point.

You consider 50 a lot higher than 47? (Assuming mxm4 18")

Over inflating isn't too much of an issue. Are you using the TPMS for the reading or a tire gauge? The TPMS are not terribly accurate and will also get affected by warmer tires. You should check air pressure with a tire gauge with cold tires.