How to avoid getting the shaft
BRIAN TURNER
With little exception, it doesn’t matter what you drive, it has a driveshaft. Whether it’s the constant velocity joint half-shafts on a subcompact or the two-piece behemoths on full-size pickup trucks, we all rely on driveshafts to put the power from our engines and transmissions to our wheels. Driveshafts have improved in technology and performance — and these upgrades have also brought higher repair bills. But there are some ways to save serious coin when dealing with driveshaft repairs.
Keep your boots on: If you drive any type of front-wheel ride, it uses two driveshafts — one for each wheel. These have constant velocity joints on either end to allow them to “stretch” and “contract” as the front wheels turn during steering manoeuvres. These joints are packed with grease to avoid metal-on-metal wear, and have synthetic rubber boots to keep the grease in and the dirt out. The problem is that the boots are prone to any medium to large road debris striking them, causing cuts and tears. If a joint spins long enough with a severe cut in its boot, all the grease will fly out and the joint will soon deteriorate and fail. The most common symptom that occurs before this impending doom is a rather loud clicking noise that comes from the front end on sharp turns.
Boot kits (with new clamps and grease) are relatively inexpensive compared to the entire shaft. Boot kits range from $20 to $80, while shafts can cost more than $300. Good oil-change techs will check these at every service, but a torn boot can devolve into a driveshaft replacement in a few days of driving. If you notice grease sprayed up into the front wheel wells, get down with a light and take a look at the driveshafts, and if a boot is torn, get it changed right away.
Rear-wheel driveshafts can be a pain in the rear. Driveshafts to the rear axle on a rear-driver used to be a pretty simple affair — a straight hollow steel tube with a universal joint mounted on either end.
When truck makers decided they had to ride more like a luxury sedan, the suspension changes meant that the driveshafts had to join the 21st century in terms of being more flexible. If a driveshaft can’t flex correctly under varying load and suspension ride-heights, it will cause a very uncomfortable vibration.
This brought in the era of the two-piece rear driveshaft and some very complicated joints, known as card-an-style or spicers. The problem is that they’re not designed to be replaced, so changing the entire shaft is the only alternative that most consumers are offered. Check for a driveshaft rebuilder in your area as a cheaper alternative.