Tire pressure in winter months

Hello! Has anyone noticed their tire pressure light on the dash comes on when it gets cold? Everything looks and feels fine to me, and it wasn't on before it started snowing.

 

Yes. This is common. You can lose about 1 psi for every 10°F. You should add air if the weather is going to sustain at lower temps.

 

Thanks! Gonna check the tire pressure today.

 

Mine starts flashing and loosing air around this time of year.

I just added 5lbs in each for winter.

 

To echo already mentioned replies, it's very normal. Lower temps = lower pressure. That's why you should check your tire pressure with the tires warm because that's the temp it will be on the road.

Personally I keep tire pressures lower in the winter as it improves traction on mixed snow/ice covered roads. Plus the ride is cushy on my tushy when the snow isn't mushy.

 

I used to keep mine serviced with nitrogen and never had issues with the tire pressure light. Now that I am in Virginia can not seem to find anywhere that services nitrogen so tire pressure light is on everytime weather changes.

 

@don3032 if there's a Costco out there they might have nitrogen I know the one by me has it at there tire center.

 

So do you suck all the air out and add nitrogen. If you just top off what are you accomplishing. When dealers try to add nitrogen to the purchase I tell them to remove it or I walk.

 

Actually most of the air would be let out, but nitrogen is an inert gas, and removes most of the oxygen in the system, They have been using it for years on aircraft inert the fuel tanks and to keep the tires pressurized.

 

I am not flying a plane or driving a race car. I will stick with plain old air at 78% nitrogen.

 

I'm not sold on the notion that nitrogen filled tires are immune from pressure fluctuations based on temperature.

 

https://www.youtube.com/watch?v=bCnWvMleVD0

 

30 year aircraft mechanic here...

We used dry nitrogen for tires, landing gear struts, and other pressurized systems that are critical safety of flight for CORROSION purposes - not pressure loss.

No oxygen, no corrosion.

Even with dry nitrogen, aircraft tires lost pressure when it got cold. We routinely serviced them.

 

This post wins the interwebz for me tonight.......Bravo!

 

That was my understanding. Nitrogen is a money maker for dealers. Easy sell to the uniformed.

 

Somehow Aussies say things better

 

RIGHT to the point.

 

I thought the 32 psi (for example) listed on your door sticker is the cold pressure and if you adjust your tire pressure to that when they're warm, they'd actually be under inflated.

As a side note, either the stealership didn't inflate my new tires correctly or they lost 10 pounds in the last week.

 

I'm thinking warm tires would show more pressure than cold tires. The air is heated and expands. Hence, the increased pressure.

 

If you check warm the pressure will be higher and that is why light comes on in cold weather. Dealerships got mine wrong all the time. I had BFGs on Tacoma and now Tundra. I asked the service manager what is so difficult about opening the door and checking the sticker which shows 46 psi. Pissed me off when I had to get compressor out and fill 4 tires.

 

Yeah, so if they're 32 psi when warm, they're less when cold.

To put it another way, if they're supposed to be 32 when cold, they're supposed to be more than that when warm.

 

I thought is was common knowledge to always adjust tire pressure when cold. Haven't checked mine for a few Months, but since the cold weather has set in here i noticed they were all like 4 lbs. down. I set my 20's at 32 front and 35 rear which is above the door sticker info, but i think it gives my truck the best ride...

 

I agree and know that tire manufacturers suggest checking and confirming pressure when the tire is cold. However, in the winter I don’t. Here is why:

In my experience, when I tested a cold tire, and it’s winter and well below freezing, the tire tended to be over inflated after 20 minutes of travel. In some cases going from 32 psi to 40 psi or more after they warm up. So in the winter I have a target warm PSI that the tire pressure sensors show and I validate with a separate gauge

With vehicles other than a Tundra, I have experienced over inflation warnings when setting tire pressure cold when we are during a cold snap.

Again, this is only what I do in the winter and I’m also in Canada. It may be controversial, but I am ok to be slightly under inflated at warm up vs being overinflated on ice/snow covered roads.

Your results and definition of winter may vary.

 

Sorry, but i don't understand how you are getting higher pressure at much lower temps. It defies all logic. Higher temps always mean higher pressure, but whatever works for you is all that matters.

 

Costco does. I thin many of them now have self fill stations near the tire center

 

They are not immune, just not as much. With my truck parked outside, my tire pressure will change by 5 PSI after i drive the truck. THE temps are right now are 40s at night 70 plus in the day time. I wouldn't pay a dealership for it as an add on or extra but if you can find a place that doesn't charge it was worth it to me. The shop where i bought my last tires services with nitrogen for free.

 

Thats not what I am trying to say and sorry if that’s the way it sounds. Colder temps = lower pressure.

Our temp swings here also have a lot to do with it. Recently we went from -20 to +20 C in the course of a week.

If I set the cold psi at -20C at 35 psi, it will be higher psi at operating temp. For fun sake, let’s just say it’s a 7 psi increase with 40 degrees C of temp change and we are at 42.

If it’s +20C and I set it to 35 psi, the tire will still increase pressure at operating temp, but it won’t go up by 7 psi to 42. Will will only increase pressure by about 3 psi to 38 psi because it isn’t expanding as much.

The larger the difference between ambient and operating temp, the larger the difference between cold and warm psi. So setting cold psi at -20C isn’t as reliable as setting it warm.

If my logic is wrong, call it out. I like learning.

 

Is this show supposed to be funny?

 

https://en.wikipedia.org/wiki/Boyle's_law