Slime seems to be OK down to 10* or maybe a little lower. Below zero, it is stiff, and will settle to the bottom of the tire, and take a while before your wheels 'balance out'. Even then, it isn't too bad if you go slow for a little while until it gets spread out inside the tire, and don't do much high-speed driving. Also, I have found different brands of sealant stiffen at different temperatures, but couldn't tell you which would be best for cold weather.

 

I changed tires last spring and the slime had turned hard in one. It had only been in there about a year.
Anyone else had this happen??

 

I HAD SLIME IN SOME ATV TIRES FOR 5 YEARS WHEN I CHANGED TIRES IT WAS STILL LIKE IT WAS
WHEN I PUT IT IN AND IT WORKED REAL WELL FOR ME