Differential Distress: Does Your Older Vehicle Need A Rebuild?

It would be nice to be in a position to buy a new car, so you don't have to worry about repairs for years, but not everyone has the budget to do so. You own an older car which you bought through a private sale, so it has no warranty. You have recently noticed that it makes a slight rattle and hum while driving, so you are now concerned about what is going on. When an older car with high miles on it starts to show certain signs, then you need to know about differential problems.

What is the differential?

When you drive your car around a corner, the inner and outer wheels need to move at a different speed to help it complete a turn. If the wheels were all spinning at the same rate, then the move would not be smooth. If your car is a rear wheel drive, then the differential is located on the rear axle. A car which is all-wheel drive has a differential located on both the front and rear axles. If you don't know what type of drive system your vehicle has, then check the owners manual to find out. Many car manuals are available online if you do not have one for your car.

Signs of differential distress

Once you know what sort of drive your car has, you can determine whether the axle with the differential is showing any of these signs:

• Noise is the primary indicator of a differential problem. In particular, if you hear a high-pitched whistle, clank or rumble emitting from the axle.
• A vibration felt while driving on the motorway is the next sign. As the condition worsens, you will feel the vibration even when driving at lower speeds.
• You may feel as though you are driving your car through a forcefield because it is so sluggish to move forward smoothly.
• You find puddles of differential fluid leaking beneath the axle.

Any of these indicators means your car needs to be inspected by a mechanic now for a possible diff repair.

Rebuild or repair differential

The decision to rebuild, repair or replace your differential depends on what is wrong with it. For example, if the problem is a leak, then the seal needs to be replaced, but the car is still drivable as long as the differential oil is topped up. If the gear wheel in the differential is worn, then the whole unit needs to be rebuilt.

Don't let a noisy or vibrating differential leave you broken down on the side of the road. If you currently notice these symptoms, get further advice from a qualified mechanic.