What is everyone running for tire pressure in their winter tires? Do I want to run these on the higher side between 38-40?
No you should never put extra air into a winter tire. Put the specified pressure for your car's set up that it says on the inside of your door. In winter if you fill your tire with the normal amount of air they will lose a small amount of pressure through the night, which is advantageous for when the car is cold as the tire provides extra grip. When you drive on the tires they warm up and return to the fill pressure. If you add extra air then they become over pressured when they warm up from driving.Winter tire setup
Yes this is actually correct. You should raise the tire pressure during the winter but makes sure to check the pressures when the car has not been driven and the temperature of the tire air is the same as the outside air temperature.Actually, filling tires with a bit extra air is recommended. In very cold weather tires can lose as much 5-6 psi overnight.
Now I assume that everything you are saying is true for normal winter driving conditions in the US. Where I live it hits about -20c and proceeds to fluctuate between there and -40c for the next 5 months. The roads are infrequently plowed outside the highway. For driving on more severe snow conditions on unplowed roads being underinflated will be helpful. It is like Zerobane was saying, you can float over the snow (in theory). Having harder tires is theoretically advantageous where your tires can dig down below the snow to hit asphalt, so this will be road condition dependent.Yes this is actually correct. You should raise the tire pressure during the winter but makes sure to check the pressures when the car has not been driven and the temperature of the tire air is the same as the outside air temperature.
As quoted from the owners manual...
"If you equip your car with snow tires,
they should be the same size and
have the same load capacity as the
original tires. Snow tires should be
installed on all four wheels; otherwise, poor handling may result. Snow
tires should carry 4 psi (28 kPa)
more air pressure than the pressure
recommended for the standard tires
on the tire label on the driver’s side of
the center pillar, or up to the maximum pressure shown on the tire
sidewall, whichever is less."
Lower air pressure to increase the contact patch may help unstuck grandma's Buick in a snowbank but as for NOT being stuck and driving normally through the snow or even competitively, you will want a decrease the contact patch with higher air pressure. More pounds per square inch that is directed down on the tire siping and tread will increase traction during acceleration, braking and cornering.
So to answer Chris' question, Yes, around 38-40 pounds I run in the winter.
Or you could just check them regularly.Actually, filling tires with a bit extra air is recommended. In very cold weather tires can lose as much 5-6 psi overnight.