Why is it so difficult to find a shop that can align a car’s wheels properly?
There are several reasons. Modern cars are more sensitive to wheel alignment than older models, due to the almost universal use of independent suspension plus the fact that in many cases the rear wheels also need to be aligned. The other side of the story is that in many cases the motor trade, whether from ignorance or greed, try to have a car in and out in 10 or 15 minutes, while it often takes 30 minutes or longer to do it properly. Furthermore, they often use rule of thumb settings, instead of taking the trouble to get the correct specifications.
What is the difference between static and dynamic wheel balancing?
Static balancing, also known as single-plane balancing, assumes the wheel is a flat disc, ie, the width is not important. A spinning wheel will be in static balance if it comes to rest every time in a different position. Such an imbalance shows up on the road as a gradually increasing tug on the steering wheel as the vehicle speed increases.
Dynamic balancing brings in the effect of wheel thickness. For example, if you add two equal mass-pieces opposite each other on the rim of a wheel that is in static balance, in such a way that one piece is on the inside of the rim and the other is on the outside, then the wheel will still be in static balance. However, it will now be in dynamic imbalance, because when the wheel rotates the inertia of these mass-pieces will pull the wheel first one way and then the other way. Dynamic imbalance tends to show up at a certain vehicle speed, and then die down again as the speed increases.
Why does my car refuse to run straight on a lightly-cambered road when I let go of the steering wheel?
The camber does play a role, but if the car veers too soon then your first suspect should be uneven left-to-right tyre pressures. If the tyres are fine, then you should have the wheel alignment checked.
My steering has developed a lot of play. Where should I look?
Jack up the front wheels, and put stands underneath, then find somebody to move the steering wheel from side to side, while you get underneath and locate the moving steering mechanism. Expect play at the ball-joints, the idler arm, and the steering box drop-arm. The first two items are relatively inexpensive to replace, but play in the steering box will be expensive to cure, because the box usually has to be replaced.
Now that I’m getting older, I would like power steering to be fitted to my car. Is this possible?
Yes, there are a number of companies that fit power steering to older cars. Some of these can be located in the CAR Buyer’s Guide at the back of the magazine.
My power-steering unit has started to make a noise when I turn the wheel. What can it be?
A screeching noise is simply a loose steering pump drive belt, but a growling noise usually indicates that the fluid reservoir is empty. Any other noise should be investigated by a power steering specialist, not a normal garage.