This article is by no means intended to "teach" a person how to drive a tractor/trailer in slick road conditions!  Make the most of the knowledge your instructors have at your school.  This article is intended as an Overview on Winter Driving only.

Don't we all just love wintertime?  Maybe you do and I am sure the skiers of the world do, but I do not.  I've grown up in cold winters and to tell you the truth, the snow up to my neck lost all it's charm after age 8.

So now as adults we have to drive in it... The four-wheeler seems like enough to handle sometimes, but now 18 wheels?  It's enough to almost make you want to panic.... but don't.  Those 18 wheels, especially when there's 40,000+ pounds atop them, have a remarkable amount of traction.  That's the good news.  Naturally the bad news follows and it is this:  since you now have a "pivot point" you are at a much higher risk of JACKKNIFE.  I don't want to scare you, but I do want you to understand a couple easy dynamics behind it... it may save your life.

What makes a vehicle slide on slick pavement?   

Wheels that are not rolling are sliding.  Wheels that are sliding are often referred to as "locked up".  Any "locked up" wheel will go faster than a wheel that is rolling.  As a result, any locked up wheel will think it needs to go first.... it will try to lead the others.  With a tractor/trailer, if trailer wheels "lock up", the trailer will attempt to come around the tractor.  This is called a "trailer jackknife".  On the other hand, if tractor wheels lock up, they will attempt to come around and this is called a "tractor jackknife".

A skid is the "birth" of a jackknife -- if allowed to proceed, it will turn into a jackknife.  If you catch it in time, it may not.  It is said that by the time the tractor and trailer are at a 15°  angle to one another, the chances of regaining control are slim to none. The picture of the blue truck is quite a bit sharper than 15° .

What are some of the causes of skids?