Cold PSI vs at temp PSI’s

[NSCyber]

Got a new tire inflator and and filled my all-terrain tires. Was a super cold day and I noticed they were at 47/48 when I got in the car in the morning so I filled them to 52 after I drove for a couple miles and they warmed up to 48/49. Now when I get in the car in the morning when it’s super cold they are at 51 and quickly get up to 52.

After driving for a few miles they warm up to 54-55psi. Haven’t seen it get higher than that and ifs 95% street driving.

I know 50 is the recommended cold PSI but how high can get it? The tire pressure monitor tells you when it’s low but does it tell you when it gets too high?
PITA to remove the covers to take off a bar and put them back tbh. Is 55 too high?

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[bentoncalder]

“As per Tesla in the Cybertruck User Guide, the Cybertruck's tires should be kept inflated to their recommended pressures, even if it differs from the recommended pressure that’s printed on the tire itself. Tesla also notes that when a Cybertruck with All-Terrain Tires is carrying heavy loads up to its Gross Vehicle Weight Rating (GVWR), the tire pressures should be increased.”
https://shop.teslarati.com/en-ca/bl...la-cybertruck-wheel-tire-specifications-guide

 

[Kryptek]

my rear driver tire has been dropping psi since ive owned it, lowest was today randomly at 40psi when the temps climbed to 20f. I might put in a request if it keeps dropping air, should be an easy fix for them mobile or pay for a new tire install.

 

[ABILISK]

Everything you mentioned sounds totally normal. You lose a few pounds when it gets cold, air them up to 50, then they get up to 55 after driving for a while. All totally fine and expected.

 

[HaulingAss]

Got a new tire inflator and and filled my all-terrain tires. Was a super cold day and I noticed they were at 47/48 when I got in the car in the morning so I filled them to 52 after I drove for a couple miles and they warmed up to 48/49. Now when I get in the car in the morning when it’s super cold they are at 51 and quickly get up to 52.

After driving for a few miles they warm up to 54-55psi. Haven’t seen it get higher than that and ifs 95% street driving.

I know 50 is the recommended cold PSI but how high can get it? The tire pressure monitor tells you when it’s low but does it tell you when it gets too high?
PITA to remove the covers to take off a bar and put them back tbh. Is 55 too high?

The AT tires are rated for up to 65 psi cold. Which means they will not explode as they warm up to 70 psi. In fact, Tesla recommends all four tires be filled to 65 psi cold for towing trailers. You also want to increase above 50 psi cold for hauling heavy loads, especially if it will be a higher speed freeway trip.

I've found the AT tires work best at around 52 psi cold when lightly loaded (1 or 2 people and not much cargo). Any less than that and the tires suffer when driven hard in the corners. I tend to carry a lot of corner speed, rather than slowing way down for corners and then speeding back up. That kind of driving calls for a bit more pressure than slow, easy driving on mostly straight roads because higher pressure s work to prevent the outside of the treads from wearing faster than the center from hard cornering.

If I will be driving most of the day on backcountry unpaved roads at speeds below 50 mph I take out 10 psi (down to about 42 psi).

It's not wrong, especially in the winter, to add a couple more psi to accommodate potentially colder weather or the gradual leakage of air from tires. In cold weather you will get less temperature rise due to driving (and thus less pressure rise). It's always easier to let out a pound or two if the weather warms than it is to add air on a particularly cold morning. Air will escape right through the rubber even though quality tires have a liner inside to slow down the natural loss of air. Air will also seep out (on a microscopic level) right past the valves in the valve stems and caps. If you don't have valve stem caps dirt can find itself between the valve seals and allow air to gradually seep out faster.

Air can also leak past the tire beads, especially if the wheel has nicks in the bead area or is not perfectly clean and smooth when the tires are mounted.

The OEM AT tires with good valves and caps, and clean rims in good condition should lose less than 1 psi every 2-3 months, assuming the measurements are taken at the same tire temperature. Since it's generally better to be over than under, it's not wrong to air on the side of more air when doing tire maintenance. The only exception is in the spring when you know warmer weather will be coming. Of course, it's super easy to bleed a little out if a warm spell hits suddenly but, for typical spring warm-ups around here sometimes the natural loss of air over time keeps the pressures pretty close to where they should be as spring turns gradually into summer.

Tire pressures can and will rise from warmer weather or extended driving, that's normal, but the tire can never gain air on their own (unless someone adds air), tires can only lose air.

 

[RAY INGRASSIA]

Thanks all for feedback. Weather hot and cold here in Florida, but a royal PIA to adjust needed tire pressure having to take hub caps on and off. Personally, this was stupid and don't remember having to do this since the 60's

 

[NSCyber]

Thanks all for feedback. Weather hot and cold here in Florida, but a royal PIA to adjust needed tire pressure having to take hub caps on and off. Personally, this was stupid and don't remember having to do this since the 60's

Yes. Thank you everyone for the help. My thoughts exactly. Love the look but really a huge PIA taking them off and back on.

 

[igs]

50 psi is when loaded with 5 occupants. You can probably go lower otherwise.

 

[DJAlan2000]

my rear driver tire has been dropping psi since ive owned it, lowest was today randomly at 40psi when the temps climbed to 20f. I might put in a request if it keeps dropping air, should be an easy fix for them mobile or pay for a new tire install.

Same tire? After tire rotation does it move or is it still dropping on the rear driver's side?

 

[Crissa]

Often when the weather dips low, one corner of your car either is colder or swings temperatures more wildly, and that makes a little air come out of it. Nothing is completely sealed! Where and what direction you park can have a big difference, too. Is there slope, shadow, etc.

When you get a big swing in temperature, in the morning check the pressure and bring it back to the label. Check it a day, a week later to see if you see the same pattern. Try parking in a reversed position in relation to the sun, see if that fixes it.

If the disparity in pressure keeps following the wheel, then you worry.

-Crissa

 

[Jackmaine]

There is a warning if the tire pressure gets too high. I have seen it on a Model Y.

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