We have used snow tires (Big-O Bigfoot) on our SUV since it was new. It has 3/4-inch high chevrons, etc. When snow accumulates on the road, isn’t this still the tire of choice? In the summer, we use these tires with tread worn to less than 1/4-inch high; we mainly drive the SUV in the winter.
We were using winter tires year-round on our sedan, but we just switched to all-season tires in the summer and Blizzak tires in the winter. We changed over because one of the winter tires was damaged by something on the road in summer, and replacements weren’t available. I didn’t want to drive with a tire with a bulging sidewall, and these tires had maybe 5,000 miles of tread on them, so it wasn’t a big loss. – David in New Mexico
Bigfoot-brand tires are not widely available in Canada. A major independent retailer in the United States with more than 500 franchises, Big O has recently made inroads into this country with outlets in British Columbia, Alberta and, more recently, Ontario. Big O outlets sell a variety of tires from name manufacturers as well as its own store brand wearing the “Bigfoot” name.
But there are several unknowns about your Big O tires that prevent me from a detailed answer. Which of the several types of Big O tires are they? How old are they? What is the “chevron” you mention? Whether they are designed for or good in snow I don’t know, because you do not mention which of the many styles of Big O they are. If the symbol on the sidewall is the M+S designation, that does not mean they are good in winter, merely that they have been designed for mud and sand, i.e. clearing the tread in mud and snow.
If the “chevron” you mention is the “snowflake within a mountain” symbol, that signifies they are rated for winter or cold conditions. Winter tires carry that rating more for their ability to remain flexible below freezing, than any ability to dispel snow from the tread.
In fact, most winter-rated tires do not have large open grooves or channels. Instead the emphasis is on maximizing the amount of rubber in contact with the road to ensure the best grip on slippery surfaces. By contrast, the M+S symbol means that at least 25 per cent of the tread area will contain voids or grooves.
There is no testing involved in obtaining or using this rating. The Rubber Manufacturers Association and member tire makers agree on the testing used in order for a tire to carry the snowflake in a mountain symbol for tires rated for severe winter use. You mention 1/4-inch of tread. Tread depth is measured in 32nds of an inch. Most new light-truck tires have about 14/32nds to 16/32nds of an inch of tread when new. Minimum safe tread depth is considered to be 2/32nds of an inch. Your tires are currently at 8/32nds so well within the safe range.
Unless they are old. It is generally thought that tires have a life expectancy of five to seven years. The Big O warranty extends to six years. If your tires are past that age, the warm and dry summer months in your state would have caused them to dry out and some of the critical chemical elements in the compound to evaporate.
Bright lights
I overheard a conversation at a social gathering the other night. A bunch of “car nuts” were talking as I walked by. I know these guys well and respect their knowledge but what I heard intrigues me. One of them said “the biggest difference between cars here and in Canada has to do with lights.” What the heck does that mean? – Trish in Bethesda, Md.
Lights are an issue in the United States where daytime running lights are not mandatory as they are in Canada.
This means that people can drive along in conditions of poor visibility such as fog, snow, heavy rain, etc., or at dusk or dawn with no lights showing to warn other motorists of their presence.

