Gordy’s Garage: Traction Controls
MINNEAPOLIS (WCCO) — Does your car have traction control? If your answer is “I don’t know” then it is time to get out the owner’s manual.
A lot of front-wheel-drive vehicles have this feature. It uses the anti-lock brake system (ABS) sensors to detect wheel spin, and then applies the brake to the spinning wheel. This — in theory — sends power to the other wheel, and if it spins, braking is applied to that wheel. The bottom line is that this braking should equalize power to the two drive wheels, resulting in forward motion on slippery surfaces.
This does not always happen. On a really slippery surface, so much braking is applied to the wheels that very little power is applied, and you might go nowhere. The important thing to know is that most traction control systems have an “off” switch, and sometimes you will do better in snow with the traction control defeated.
This button says “Auto LSD” which I believe means Automatic Limited Slip Differential. This is a bit misleading. Back in the day, when all cars were rear-wheel-drive, a limited slip differential was an optional rear axle that MECHANICALLY distributed engine power to both rear wheels, effectively doubling traction. We used to call a car without a Limited Slip a “one-wheel-wonder” because only one wheel would spin when traction was lost. The downside of the old-fashioned LSD was that the rear of the car would often slide sideways when both rear tires were spinning.
When the traction control button is pushed in modern cars, you get an indication like this that tells you the system is off.
I tried this with my wife’s Ford Focus after our first meaningful snowfall: going up a hill with the traction control on, and then off. I had just put winter tires on the car, and wanted to see how well they worked on our unplowed (long and steep) driveway. I found that the traction control reduced power to the drive wheels so dramatically that the car would not go up the hill.
I turned the traction control off, and with some good old-fashioned wheel spin, I was able to make the grade. This is something you may want to try with your ride, but be aware that spinning wheels mean much less steering control. So, practice far away from other cars and your neighbor’s mailbox.
And it is NEVER a bad idea to read the owner’s manual.