Diagnosing common driveline and differential problems can sometimes be a little difficult.

Let’s talk about some of the noises what types of problems those noises signal.

This is a powertrain and regardless of what make of vehicle you drive the powertrain is basically the same.

 

LOOSE PINION BEARINGS

If you hear a whining noise when you are slowing down or when speeding up at any speed you hear a whine with a hum or a growl it could be a loose pinion bearing which looks like this:

Now the noise when speeding up could also be a worn gear set.

WORN GEAR SET

A worn gear set could be due to a lack of lubrication or overload.

The noises you will hear which point to a worn gear set are; howl without whir or rumble during acceleration at any speed or howling while accelerating over a small speed range.

Your powertrain gear set should look similar to this

Now what if there is howling after the gear set installation? The problem here is more than likely the installation was done wrong or faulty gears.

CARRIER BEARINGS

If you have a low-pitch rumble at all speeds over 20 mph then more than likely you have worn carrier bearings. Basically these look like this:

 

WORN PINION BEARINGS

You are likely to hear whirring during acceleration or deceleration at about 10 miles per hour if your pinion bearings are worn.

BAD WHEEL BEARINGS

If you are hearing rumble or clicking that gets worse during hard turns you’re more than likely going to find that you have bad wheel bearings.

U-JOINTS

Driveline squeaking or grinding at any speed or clunking during takeoff generally points to worn or damaged u-joints. The clunking during takeoff can also be caused by worn spider gears; worn axle splines; excessive gear backlash; loose yoke splines; worn slip yoke splines. As you can see it is probably best to take the vehicle to a mechanic who has the ability to check those items for you and discover exactly which it is. This is a U-joint.

DRIVESHAFT

If you hear Steady vibration that increases with speed; this could be either your driveshaft being out of balance or worn u-joint. The driveshaft looks like this;

It is possible to fix these items yourself so long as you are sure that the noise you hear is the right part since some of these noises can be a sign of one or more parts.

If you do not wish to spend money on parts you do not need then it is best to take your vehicle to a driveline service shop you know and trust and have them diagnosis which part is the actual culprit.

Another way to save money is to buy the part from your parts store and then have your mechanic put it in. In some cases this will save you a few dollars in the markup most garages put on items.