What does the expression "steering wheel holders" mean?

I'm a steering wheel holder and I couldn't be happier. In fact, I am proud of it. The equipment is not mine. Since I get paid for every minute I work, if the there is a problem well, it's not mine. And if the company problems involve you loosing money. I guess it's time for you to look for a better company to work for.

 

Back when I started in1980 there were a lot of drivers that had their wives/girlfriends and some times sons and daughters with them that weren't drivers but could hold the truck between the lines while the actual driver took a nap. The women did the paperwork and were an extra name and body in the truck in case the DOT was on the prowl. They'd switch out going down the road, normally in some area where there wasn't a lot of traffic like TX.
It made my life more difficult because people would see me and think I was a steering wheel holder, It's always been that way and even today I run into places that still don't get that women own and drive trucks.