Next to the brakes, there is probably no more important component on your truck than the steering system. When you get right down to it, the level of control that you have over that massive hulk of metal as it thunders down the highway is only as good as the network of rods, bushings and bearings that pass the commands to the steering axle.

Luckily, the steering system is also one of the simplest places on the truck to troubleshoot minor problems before they become bigger ones. Because you are physically connected to the steering system through the steering wheel, you can easily sense the slightest changes in performance, whether it be a slight pull to one side or a persistent shimmy at high speed.

A wide range of factors can cause steering problems, from something as simple as loose lug nuts to something as serious as an axle shifted on the springs. Setting up the steering system is a complex task that involves setting the caster (the relationship of the steering axle to the road), the camber (the vertical orientation of the wheels), and the degree of toe-in or toe-out. And an improperly aligned system simply will not allow the vehicle to roll or turn as freely as possible.

On top of that, the steering system contains all kinds of moving parts, including bearings, tie-rods and linkages that are constantly pulling and pushing on each other.

According to John Lewis, the Barrie, Ont.-based maintenance manager for SLH Transport, the key to troubleshooting steering problems is being specific.

“It is essential for the driver to describe exactly what is happening, or else it could be any number of things.” Lewis explains. “You have a driver come in and say, I have a wobble in the steering.’ Well is it a wobble, or more of a vibration, because they’re different… If you can get an accurate description of what the problem is, then you can start eliminating sources.”

And that description goes beyond describing how and when the problem occurs, adds Lewis. Details about road conditions can also shed light on that persistent vibration you’re feeling in the steering wheel.

“If they think the truck is pulling to one side, maybe they have been traveling on a road with a high crown and the alignment needs to be set up so the camber balances that off. If he runs a lot on rough roads, maybe the shocks are worn out.”

The load can play a part in steering problems as well, Lewis says. “If the fifth-wheel is all the way back and the weight distribution is wrong, the driver may be going down the road with the nose of the truck not completely on the ground.”

As with most things in life, the best place to begin troubleshooting a problem is with the most obvious source. In the case of steering problems, that usually means the tires. Low or uneven tire pressure is often a primary culprit in hard steering, wandering, shimmy or vibration, and pulling to one side. Tire pressure also plays a big role in uneven tire wear.

Hard steering can also suggest another simple problem, says Jim Pinder, maintenance manager for Volvo Trucks of Waterloo. “It can come down to a power-steering fluid problem,” Pinder says. “Maybe there is a leak or the filter is clogged, or has never been changed. That’s just preventive maintenance, and people forget to do it.”

Pinder also looks to the hydraulics when a steering system is having trouble recovering from a turn.

“If there has been work done on the hydraulics, and the system wasn’t properly bled, it is possible to get an air lock that stops the wheels from coming back,” he explains. “The truck really has to be jacked up, to take the weight off the system, and bled at the steering box so the system is fully cycled.”

If the tire pressure is good, and the hydraulics are functioning correctly, a persistent steering problem may be linked to a worn or broken component. If something is broken, the driver can probably trace the problem to a specific event. “Maybe the driver went over a curb or went off-road briefly and didn’t think it was a big deal at the time, but one of the steering components got damaged or knocked loose,” Pinder says.

It is also not uncommon, he says, to have a single bad component throw the whole system out of whack. A bad tie-rod end, for example, can cause one of the wheels to toe-in and the wheels end up fighting each other. Interestingly, Pinder feels some of the newer steering component technology is often to blame for premature wear.

“In the last few years, we have been seeing more of the maintenance-free components, but I don’t think they get the same life out of them,” Pinder says. “We are going back to the greaseable components, and I think people will be looking for those on the aftermarket. But even with greaseable components, it’s important to jack the truck up to take the weight off it to make sure the grease gets right through all the components.”

Excessive play in the steering system can also often be traced to worn components, Pinder adds.

“Often it is a U-joint in the steering column, and that comes down to a lack of maintenance again,” he says. “Some steering components are often not maintained because they are right up under everything and they are just hard to get at. They shouldn’t be overlooked.”

Both men agree that one of the keys to easy steering is a good alignment, including both the front and rear axles. Obviously, if the axles driving the truck along the highway are trying to go in a trajectory slightly different from that of the axle steering the truck, the driver is going to be forced to compensate for that difference in the cab. To the driver, a misalignment translates into a pushing sensation in a turn or a persistent pulling to one side.

“If the axles are out of alignment, you could have a truck that feels like it’s going down the road sideways,” says Lewis. “If you can get the truck running straighter, it is going to steer better.” n