EXTREME cold temps ... Flat tires.

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1,410
Location
Western Canada
Thread starter
Temperatures have plummeted, we are seeing morning lows of -22*F ( -30*C ) and colder. Last week temps were around 30* F. ( -2*C ) Yeaah ... I have also seen numerous flat tires around the city. Yesterday I saw 6 cars / SUV's with flat tires. WHY so many flat tires ? Is it the usual failure to check the tires for 6 months ( or ever ... ) and get caught out with a very low tire that now loses 5 or more psi just because of the temperature change ? Tire pressure will drop roughly 1 psi per 10*F temp drop. Or is there more to it. Do tires simply become so stiff in the cold that they sometimes lose their seal if they are under inflated by a large amount ? I remember reading somewhere that people living in extreme cold climates sometimes run tubes in their tubeless tires, because below a certain temp, tubeless tires no longer seal reliably. Thoughts ?
 
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16,695
Location
NH
Totally flat or mostly flat? I wonder if they were low going into winter and then just dropped that much more. Maybe a few were mostly flat, got driven on and took enough damage to finish the job. Of course, it could just be a fluke. Correlation not being causation and all.
 
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1,896
Location
missouri
Just my theory. Your air pressure falls with the temp. If one was already low, like with a nail in it and only about 15PSI, the liner will no longer seal to the nail and flat here we come. Also, pressure too low, and bead fails to seal. It seems people do not like to stand out in the cold and air up tires. I do it, and I do not like it and cold here is 40F. at -20 I would really hate it. Rod
 
Here is where the 1 psi per 10 degrees F came from. I'm thinking the bead is not a pliable as when it is warmer. Also, some of those tires might not have been topped up in a long time. A lot of people drive at 20 psi instead of 30 and never notice it. Meanwhile the TPMS indicators are lighting up like Christmas trees in Alberta and Saskatchewan. https://en.wikipedia.org/wiki/Cold_inflation_pressure.
 
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14,199
Location
Central NY
Aluminum wheels and bead leaks. An ex of mine had a Honda with aluminum wheels that just would not hold air below 20F. I cleaned up the beads, sealed ... no luck . Had multiple shops clean up the beads and seal, no luck. New valve stems with sealed and cleaned the surface, still leaked. Even did new tires. My suggestion was steel wheels but that was not well received.
 
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578
Location
Alberta
I think it's a combination of low pressure due to very low temperature, and (as Snagglefoot said) a non-pliable tire bead. I've noticed the same thing every winter, more flat tires in really cold weather.
 
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3,277
Location
On another site
If you run your tires at low air pressure <span style="font-style: italic">any</span> time of year, you will see more flats… People just don't keep up with their tire pressure when the temperature drops.
 
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251
Location
Missouri
Low tire pressure causes excess flexing and the tire overheats and fails. Ever notice all the boats and campers that have flat tires on the first warm day of spring? Folks don't check 'em and they are low and overheat.
 
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35,852
Location
ME
I checked and overfilled my wife's tires two winters ago right before we had that -20F cold streak. I did not want any problems-- pure survival mode. One went flat anyway the next morning. I think it was a piece of ice, from condensation from the summer air, jamming the valve core open slightly. It was about 10 above when I did that. I try to use dry air from dry days to inflate my tires, but still got burnt. This is where TPMS shines-- one doesn't have to invasively check pressures. Of course they're four more batteries to take a dump in the cold.
 
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1,410
Location
Western Canada
Thread starter
Originally Posted by Oily_Thing
Low tire pressure causes excess flexing and the tire overheats and fails.
Sure. Except that it was -22*F this morning. Heat is not the issue at these temps.
 
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3,811
Location
Somewhere in the US
Just an FYI: The Coefficient of Linear Expansion for steel is twice that of rubber, and for aluminum, it's 3 1/2 times. That means the wheels will shrink more, the colder it gets. It should be no surprise that tires leak more when the weather gets extremely cold. But having more pressure in the tires helps, as that pressure helps seal the beads to the SIDES of the wheel flange.
 

Ws6

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3,065
Location
South Central US
Got down to -15 last year. I had zero issues. TPMS didnt even come on. I doubt that extra 10* would drop me from not even provoking the TPMS to "flat".
 
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553
Location
Vancouver, Canada
Tires do lose air pressure in the cold, it's a fact. To test the concept - have an empty pop bottle capped tight at home temp and then take it outside - you'll see how it contracts, same thing with tires.
 
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1,449
Location
iowa
Originally Posted by dubber09
Tires do lose air pressure in the cold, it's a fact. To test the concept - have an empty pop bottle capped tight at home temp and then take it outside - you'll see how it contracts, same thing with tires.
Great idea on how to demostrate to other people that don't understand how important it is to match pressures, with temperatures for the conditions they will be operated at. I hear many sealed containers in my shop making little pops, when I crank up the heat when it's cold out. I keep it at a minimum of 45 degrees though, so nothing freezes, plus I have a little 5 gallon aquarium on my desk.
 
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Messages
1,479
Location
Northeast Nebraska
I know this is going to sound stupid but for years we use to here a pop coming form the kitchen. Finally narrowed it down to it coming from the fridge but couldn't get any closer to figuring exactly what it was, it was just to random. Then a few years back I stopped drinking pop which meant no more two liter bottles in the fridge. Some time after the wife mentions how we don't hear that popping sound anymore.
 
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