Tire PSI

[scaots]

I started around 42 from delivery. It was fine and had about the rated efficiency. I adjusted to 45psi after a couple months and definitely had better efficiency on average. I also didn't think it really affected the ride comfort much. I just bumped up to 47psi and I can definitely feel it in the ride. So far very limited driving I have not noticed any additional efficiency. I will keep it this way for a week or two just to monitor for any effect on efficiency, but will probably drop a pound or two for ride quality. I am on 18" Michelins.

 

[ChrisHH]

Speaking of tire pressure. My front right tire decided to spook me this morning by bringing up the low pressure warning. 5 PSI is certainly scary so I pulled over when I could and it was then 44 PSI but in RED. It did this a few times but appears to be happy now.

I can understand 5 being low, but 44 certainly is not. I keep mine at 44/45 and while on my trip to Ohio a few mornings it was 41/42 and it was not upset then. I do hope I don't have a sensor going out.

 

[zigzag]

Got TMPS alert on M3 as Temp. dropped to 40's and showing PSI to 39 and 40. How much air should I put in to get rid of the alert? Door jam says 42. Should it be higher than 42 to not get the alert?
Right now I am sitting at 41 and still getting alert. Does anyone what is the threshold for alert?

 

[cfcubed]

Does anyone what is the threshold for alert?

Answer: Yes, Tesla but they ain't saying. Read my posts to this thread just one page back for much more info.

Think 3's UI takes a comparatively long time to clear PSI alerts, e.g. 41 psi is above threshold but takes UI a while to recognize PSI has raised above threshold & continues to alert for several mins on OK 41 psi readings. E.g. watch your RED 41 PSIs turn to BLACK 41 PSIs over time driving & then alerts finally stop.

IMO Tesla is much more finicky here then other vehicles, esp for those not in beautiful, temperate SoCal, and suggest informing + escalation to Tesla if it seems more bothersome than other cars you've had (as I did). In defense I've taken to assuring all tires >= 42psi on coldest mornings.

 

[zigzag]

Answer:

Think 3's UI takes a comparatively long time to clear PSI alerts, e.g. 41 psi is above threshold but takes UI a while to recognize PSI has raised above threshold & continues to alert for several mins on OK 41 psi readings. E.g. watch your RED 41 PSIs turn to BLACK 41 PSIs over time driving & then alerts finally stop.

I think you are right that UI takes time, I was sitting on 41 and getting alert but after driving some time the alert is gone and I am still at 41 PSI. So maybe 41 is above threshold.

 

[PNWmisty]

Does anyone what is the threshold for alert?

I don't know. In 5,000 miles it's never alerted me of anything.

 

[processengr]

My experience is that 39 psi sets off warning. If you set to 40 , you will fall below that when/if temperature falls.

 

[zigzag]

Here from the manual

The Tire Pressure indicator light does not immediately turn off when you adjust tire pressure. After inflating the tire to the recommended pressure, you must drive over 15 mph (25 km/h) for more than 10 minutes to activate the Tire Pressure Monitoring System (TPMS), which turns off the Tire Pressure indicator light.

Answer: Yes, Tesla but they ain't saying. Read my posts to this thread just one page back for much more info.

Think 3's UI takes a comparatively long time to clear PSI alerts, e.g. 41 psi is above threshold but takes UI a while to recognize PSI has raised above threshold & continues to alert for several mins on OK 41 psi readings. E.g. watch your RED 41 PSIs turn to BLACK 41 PSIs over time driving & then alerts finally stop.
.

 

[jsmay311]

We are running ours at 55psi. The efficiency improvement has been worthwhile.

Disclaimer: we are crazy.

Just so everyone's clear, the Model 3's maximum rated pressures (printed on the sidewalls of the tires) is 50psi for the 18's and 51psi for the 19's.

I'm also "crazy" for efficiency, and I've routinely inflated tires above a vehicle's recommended pressure (inside the door jamb), but I've never gone above a tire's maximum pressure (on the tire's sidewall).

 

[MountainPass]

Just so everyone's clear, the Model 3's maximum rated pressures (printed on the sidewalls of the tires) is 50psi for the 18's and 51psi for the 19's.

I'm also "crazy" for efficiency, and I've routinely inflated tires above a vehicle's recommended pressure (inside the door jamb), but I've never gone above a tire's maximum pressure (on the tire's sidewall).

Yes, we would like to once again point out that we aren't suggesting anyone do this, we also don't recommend doing 360's on the track and jumping your Model 3 like us.

 

[MountainPass]

Oh and to clarify - we inflated the tires to 51psi, but when hot driving on a sun-beaten highway they get up to 55. So that is still technically within the max "inflation" pressure.

 

[TMK26]

My tires dropped to 39psi this morning (low 40s degrees outside). I got the warning. The pressure was at 41psi (when it wasn't cold out).

 

[GDN]

The temps dropped here in Dallas today. Had warnings over the weekend, so bought a new gage and inflated everything to about 44. I got in to drive this morning and 3 tires have warnings again already, one at 38, two at 39, and one at 40. Will get home and let it sit for an hour or so this evening and check them all again. Probably going to 44 or 45 on them again.

 

[Ken Voss]

Here is the issue. Tire pressure changes in ALL CARS all the time based primary on temperature. TPMS on most cars don't alert you when the pressure drops just a few PSI. The model 3 TPMS is hyper sensitive and often alerts you when it isn't necessary.

Lets say your tires are at 42PSI when you return home on a warm day after driving a few hundred freeway miles, they can easily drop to 38 PSI overnight parked outside in the cold fall air triggering a warning the next morning before you even pull out of your driveway. Once the air temperature increases and you get back on the road, the friction between tire and road warm the tires even more and they will bounce right back to 42PSI, so was the warning necessary?

I feel the Model 3 Tire Pressure monitoring system needs some logic that not only looks at raw PSI before flashing a warning, it also needs to look at the rate of pressure loss over time, temperature change and miles driven before presenting a warning.

 

[babula]

How accurate is the Tire PSI view?

I've been noticing a fluctuation between 42-45 PSI and I want to make sure I avoid overinflating the tires. In the image below I added an example, initially one tire was showing 44 PSI and after a 15 min drive it was up to 46.

Is there an ideal time to check? For example 30 mins in to a drive or something.

 

[kort677]

as the weather turns colder it affects the tire pressures, you'll need to add a few pounds of air to compensate as the weather gets colder, it is always best to check your tires when cold the heat generated by driving will inflate the readings.

 

[garsh]

How accurate is the Tire PSI view?

Very

I've been noticing a fluctuation between 42-45 PSI and I want to make sure I avoid overinflating the tires. In the image below I added an example, initially one tire was showing 44 PSI and after a 15 min drive it was up to 46.

Is there an ideal time to check? For example 30 mins in to a drive or something.

Yes, check them when they're cold.

The max pressures listed on the sides of the tire are cold temperatures. It's ok for tire pressures to go higher than this when warmed up.
Reference:
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=196

 

[babula]

Thanks guys. Ideally I would like to check it while parked and before driving, but it usually starts showing up after I drive a mile or something like that.

 

[garsh]

Thanks guys. Ideally I would like to check it while parked and before driving, but it usually starts showing up after I drive a mile or something like that.

Just use a tire gauge to check pressures when cold.

 

[Feathermerchant]

Yeah old school tire gauge.
ALWAYS measure tire pressure cold. ie after the car has been idle 8 hrs or so and before driving a mile.
NEVER let air out of warm/hot tires in an effort to fix the tire pressure.