Winter Tire Pressure / PSi

[jwheaton]

Hey, I'm trying to figure out what I should set my tire pressure to, on my winter tires. I am using:

Stock 18" rims with TPMSMichelin X-Ice XI2 245/45/18

When I had them put on, they filled them to 32 PSi.The problem is that Where I live (Northern Alberta, Canada) it is very cold... about -22 C today and that is about 10 degress warmer than it has been for the past few weeks.

The pressure seems to drop by about 7 PSi down to 25-26 when I go out, especially if I park the car outside for any length of time.

What PSi do you guys recommend? I don't want to get uneven wear but I dn't want dented wheels or lack of traction etc etc either.

Any suggestions would be great.

[M4T5]

I'm not accustom to the northern climate as I live down south. In my opinion, if your going to be driving the car normally, I would put the PSI that your door sill sticker states for you place in your tires. I usually raise the PSI up 1 or 2 psi higher than recommended in the cold season. That keeps my tires at its recommended tire pressure. I check mine every two to three weeks. My 07' M45 calls for 35 psi in all tires (245/45/18). I keep mine between 36-37psi. Though do not go over your tires recommended MAXIMUM RATED air pressure.I hope this helps you out some.

J

[tytamto]

You may have to vary your pressure with outside temps. All gasses expand when heated and contract when cooled. Fact of life. Some claim that pure nitrogen is more resistant to temp changes, and race cars use it, but not sure if it would help in your case. And that is a discussion for another thread.

Fill your tires up to what the recommended pressure is on a cold day. Reduce the pressure when it warms up. More work for you, but better for your tires in the long run.

[infinitiandbeyond]

Consider Nitrogen.

http://getnitrogen.org/

Put your zip in their locator.

[Q45tech]

The tire contact patch shape and area only depends on the psi. If a rear tire has 800 pounds on it and is inflated to 35 psi the contact patch is ~~800/35= 22.857 square inches. At 50 psi it would be ~~= 16 square inches

[szh]

Hey, I'm trying to figure out what I should set my tire pressure to, on my winter tires. I am using:

Stock 18" rims with TPMSMichelin X-Ice XI2 245/45/18

When I had them put on, they filled them to 32 PSi.The problem is that Where I live (Northern Alberta, Canada) it is very cold... about -22 C today and that is about 10 degress warmer than it has been for the past few weeks.

The pressure seems to drop by about 7 PSi down to 25-26 when I go out, especially if I park the car outside for any length of time.

What PSi do you guys recommend? I don't want to get uneven wear but I dn't want dented wheels or lack of traction etc etc either.

Any suggestions would be great.

A cold tire pressure setting should not be allowed to get below the load index capacity of your car. Unsafe at that point!

So, I'd pump it up to 34 psi minimum (cold measure - before the sun has a chance to get to it) and then let it go up from there as you drive. Is your garage heated? If so, pull out, let the temp settle a bit and then measure!

In your climate, I'd also take a reading every week and adjust accordingly.

Remember that the max pressure of most tires today is about 51 psi, so even if you set it for 34 psi, it will not change that much as you heat the tire up while driving.

Z

[zozoka1212]

Hey, I'm trying to figure out what I should set my tire pressure to, on my winter tires. I am using:

Stock 18" rims with TPMSMichelin X-Ice XI2 245/45/18

When I had them put on, they filled them to 32 PSi.The problem is that Where I live (Northern Alberta, Canada) it is very cold... about -22 C today and that is about 10 degress warmer than it has been for the past few weeks.

The pressure seems to drop by about 7 PSi down to 25-26 when I go out, especially if I park the car outside for any length of time.

What PSi do you guys recommend? I don't want to get uneven wear but I dn't want dented wheels or lack of traction etc etc either.

Any suggestions would be great.

Go higher. I live in Ontario and we have some cold like you have. This week the lowest is -29 celsius.

What I usually do is summer leave it at 33-35. Winter go up to 37-38. If it is already really cold like -25, -30 I just pump 35 psi and when the temperature gets higher the pressure raises too. At 0 celsius I just pump 37 psi.

It gives you lot better traction also with a little higher pressure in deeper snow or on ice.

I have nitrogen in the tires. They don't make much differences.

zozo