Suspension: replace in pairs for greater safety
Sadly, the motor repair trade tends to suffer an unfair reputation of not always having the customer’s best interests at heart. As with any profession, I am not denying the existence of the occasional ‘bad egg’, but I have found that customers tend to view good advice that might cost extra with extreme suspicion.
Take the balanced approach
You may think that a suggestion of replacing parts that have not failed is crazy but your mechanic might have a point.
Take a broken suspension spring as an example. When spotted, many motorists would agree to have it replaced immediately. Yet, they are likely to baulk at the suggestion of doubling the repair cost and having the unbroken part on the other side of the car renewed as well. While the unbroken spring has not failed, it will be worn. Mixing new and used components on the same axle might pass an MOT Test but also introduces an imbalance that impacts on braking and handling efficiency. Having both springs replaced is the best practice.
Renewing other faulty components singularly can also create an imbalance, which can increase stopping distances and enhance the risk of you getting into a skid. Shock absorbers/dampers, ball joints, certain bushes, suspension arms and even tyres are other components also recommended to be replaced in axle sets, for optimum safety. Therefore, ask your mechanic for advice about replacing any worn, or broken, suspension component in pairs before authorising the work.