The driveline consists of parts that make up the drivetrain, not including the engine or transmission. Two-wheel drive, four-wheel drive, and all-wheel drive are terms used to describe the type of driveline in a vehicle. The drivetrain consists of everything within the chain from the engine to the drive wheels. The driveline is made up of everything after the transmission. This includes all of the driveshaft, axels, joints, differentials, and wheels.
Diagnosing differential or driveline problems can be difficult, but often times noises, vibrations, or other driving characteristics that are not normal for your vehicle can help diagnose this problem. Whirring noises only when deceleration can indicate bad pinion bearings or loose pinion bearing preloads. It doesn’t typically indicate bad ring and pinion gears.
While accelerating, if you hear a load whine or howl, that can indicate a worn ring and pinion gears or it can actually mean that the gear set up is incorrect. Worn carrier bearings can cause a rumbling or whirring sound when traveling over twenty miles per hour. The noise may even change while turning the vehicle. A broken ring or pinion gear can cause a regular clunking sound every few feet traveled.
If you experience banging or clunking sounds only on corners then this can indicate broken spider gears, a lack of sufficient positraction lubrication, or worn positraction clutches. Bad wheel bearings are typically indicated by a rumbling sound while trying to turn the vehicle. Worn u-joints or an out of balance driveshaft can make their presence known through a steady vibration that will increase as the speed of the vehicle increases. If you experience clunking only when you start out or when you let on or off of the gas; this can indicate bad u-joints, loose yokes, or a worn transfer case or transmission parts.
While issues with the driveline are typically not hard to fix, it is important that if you feel pressure while driving, hear weird noises, or your car just isn’t cooperating with you correctly, that you take it to a mechanic to be checked out. Most of these problems are easily fixed, while other may take some time. None of it is as bad as what it can turn into if ignored. If broken parts or ignored, they begin the domino effect of breaking other parts, until eventually the car will not run anymore. In the long run, it’s better to bring the car in to get checked as soon as a problem, sound, or vibration is noticed rather than waiting until there is no choice left.