Truck jack knife

One of the worst situations you can find yourself in is a jackknife. They come on fast, and usually by the time you realize what is happening, it’s already too late to take corrective action. There are 2 different types of jack knives: A truck jack knife, where your drives break traction, and a trailer jackknife, where the trailer breaks traction.

For this article, we’ll look at the more serious of the 2, the truck jack knife. What causes a truck jack knife? Simply put, the trailer is pushing the truck out of its way. This could be caused by poorly adjusted brakes on the trailer, improperly secured cargo shifting, poor road conditions, or bad driver reactions to name a few, but the bottom line is, that the truck is trying to slow down and the trailer isn’t, so the trailer is just pushing the truck off to the side. The only way to correct this is to get the truck and trailer back in a straight line. The biggest problem is, that once a jack knife reaches 15°, the chances of recovery are less than 1%. You’re basically just along for the ride. Speaking from experience, it’s not a ride you will enjoy.

To recover from a truck jack knife, the first thing you need to do is remain calm. Do not panic and overreact, as that will just make things worse. Next, take your foot off the throttle, and depress the clutch if you have a standard transmission. Steer the truck in the direction the rear axles are sliding. If the axles are sliding to the right, steer to the right, keeping the steer tires pointed in the direction you want to go, and use light pressure on the trailer hand brake to slow down the trailer, which should bring the truck back in line. Do not use the foot brake pedal, you only want the trailer brakes coming on. Sounds pretty simple, but remember you have less than 2 or 3 seconds to react, and it will take at least 1 of those seconds for you to realize what’s happening.

Don Taylor has been a professional driver since March 1985.  In 1994 he made the jump to driving tractor trailers, and has accumulated over 3.5 million miles, including over 4 years of driving turnpike doubles in Manitoba, Saskatchewan and Alberta.  He is currently hauling flat decks across North America.