Nitrogen inflation during winter?

My SUV tires filled with nitrogen from Costco are in good shape. Hardly requires refill for the winter. My sedan's tires were filled with air which require top up every couple weeks. You don't want to inflate too much for the winter as you will be losing gripping power.

It's true for free air in winter. But you paid premium for nitrogen so you don't have to.

Inclemental wrote: ↑ My sedan's tires were filled with air which require top up every couple weeks.

You need to have your tires checked - you have a leak. I have yet to add any air to my tires since I put my winters on(in early/mid november). Checked them just yesterday.


Also - air already 78% nitrogen.
Also - unless you have motorsport specific/dual valve rims on your car you will never get 100% nitrogen in your tires....

Interesting read here from Tire Rack.

warpdwhim wrote: ↑ You need to have your tires checked - you have a leak. I have yet to add any air to my tires since I put my winters on(in early/mid november). Checked them just yesterday.


Also - air already 78% nitrogen.
Also - unless you have motorsport specific/dual valve rims on your car you will never get 100% nitrogen in your tires....

If you're losing air without a major temperature swing, you have a leak. If you lose a few PSI when the temperature drops 20-30 degrees since you last checked, it's pressure loss due to temperature change.

If you fill your tires with air (78% nitrogen) at 20 degrees, they can lose about 30% of their pressure at -40. Likewise if you fill them at -40C, they'd be quite a bit over pressure at 20C.

Inclemental wrote: ↑ You don't want to inflate too much for the winter as you will be losing gripping power.

Less contact patch is better for snow and sleet - so it's actually the opposite.

er34er34 wrote: ↑ Less contact patch is better for snow and sleet - so it's actually the opposite.

That's only true when running on unmaintained roads with snow/ice, and their wheel speeds are much higher than vehicle speed so they're constantly digging into the snow/ice.

engineered wrote: ↑ That's only true when running on unmaintained roads with snow/ice, and their wheel speeds are much higher than vehicle speed so they're constantly digging into the snow/ice.

Sounds like my kind of driving

Looking forward to some donuts tonight with 10cm.

er34er34 wrote: ↑ Sounds like my kind of driving

Looking forward to some donuts tonight with 10cm.

I always leave a few zeros in the work parking lot when it snows.

So let say it is -20 and -30 now. How many extra lb I need for nitrogen?

tmkf_patryk wrote: ↑ Set it to correct pressure according to mfg specs

^^^^ just follow this. The difference in weight between air and nitrogen is minimal (+3.4%).

tmkf_patryk wrote: ↑ Set it to correct pressure according to mfg specs

eldiablo wrote: ↑ ^^^^ just follow this. The difference in weight between air and nitrogen is minimal (+3.4%).

Where do I find it? the manual only say normal pressure not for winter driving. People I talk to at kal tire say should add 5lb for winter.

follow manufacturer's cold pressure rating and nothing else. +5lbs would be excessive pressure.

vivibaby wrote: ↑ Where do I find it? the manual only say normal pressure not for winter driving. People I talk to at kal tire say should add 5lb for winter.

If you are talking about back in Nov when you were putting on winter tires but it was still warm outside, then yes add 5 lbs to anticipate the drop in temperature. But if you are checking your tire pressure *now* in the middle of winter you just follow whatever the label on your car say.

vivibaby wrote: ↑ I was told that you need to add couple pound extra for winter. Is this true? How much?

If your tires have been sitting outside in the cold, use the the cars recommended cold tire pressure spec.

If your tires are warm, like sitting inside a garage, and its cold outside, use this chart to get a general idea on what to set the tire pressure to

Simply, just check your cold air pressure every 1-2wks unless there is a major swing in outside temperature that will affect the natural expansion/contraction of air.

vivibaby wrote: ↑ Where do I find it? the manual only say normal pressure not for winter driving. People I talk to at kal tire say should add 5lb for winter.

is there a charge for it?

If there is , ask them to just put air.

Filling tires about 5 pounds/in above the rated pressure is usually ok. But the tire pressure should always be checked at "normal temperature" so I dont know how they are going to do it.

vivibaby wrote: ↑ Where do I find it? the manual only say normal pressure not for winter driving. People I talk to at kal tire say should add 5lb for winter.

Don't think you understand how PV=nRT works? You put the same pressure in but at the lower temperature. If the air never changed in the tyre--noo air leaked out or was added--when the temperature rises the pressure in the tyre will rise as well. And vice versa. So if your car says something like 35 psi inflation pressure and you inflated it at 20C and the next day it drops to -20C, then it's going to be at significantly lower pressure than it was the day before. Not because air leaked out but because it got colder. (Now I know it's not going to be a 40 C-degree difference from one day to the next in reality but just for argument's sake.) So if you put in an extra 5psi when it was 0C outside, that's going to help pressures dropping too much when it's -15C outside--get it?

So, you need to check/adjust pressures according to what temperature it is outside just to maintain that same pressure. Nobody really goes and adjusts their pressures according to the exact temperature outside though. In winter it's best to set pressures at like -10C to get a good average of what the temperatures might swing to. That's what I try to do, anyway. In summer try to do it at +25C or so. Of course if you are checking your pressures every few weeks or every month or something then you'd be adjusting more often anyway. Now I dunno about you but I hate winter and I tend to not like doing too many things outside in winter lol; so I really don't check and adjust as often in winter TBH. I have TPMS though (and most cars do these days) so it's not like a huge risk for running low pressures for too long.

This winter has been really mild (GTA) up until recently where temperatures have dropped a bit so I actually haven't got to set my pressures at a low enough temp yet. However the rest of the winter is supposedly not going to be that bad so may not even have to.

I wouldn't overthink it such that you think you have to check and add/remove air every time the temp goes up or down a few C-degrees, but just realise that if it was 0C last week and this week it's -10C, then you're definitely going to have reduced tyre pressures as a result.