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Whether you drive an AWD vehicle, or rear wheel drive, chances are you've been told that you need to have the differentials serviced. What are differentials, and why are they so important? We break it down for you to help you better understand why they need to be maintained and serviced, just like any other part of your vehicle.

What is the differential system?

Every vehicle has a differential system. It's a system in your vehicle that allows the wheels to turn at different speeds. There are multiple components to the differential system, and they are always working while a vehicle is in motion. There's the front differential, the rear differential, and a transfer case (in AWD vehicles this is called a Powertrain Control unit, or PTU) in the middle for AWD vehicles. The transfer case is what shifts power between the front and rear differentials. The differentials themselves are ring and pinion gears attached to a carrier assembly. Inside that assembly are even more smaller gears.

Why does that matter when you're driving?

Can you imagine how jerky and difficult it would be to make turns without that constant and seamless shifting of power? It would be next to impossible. Think about it: when your car is in motion, and you are making a turn, the outside wheel has a further distance to travel than the wheel closest to the turn. Therefore, the outside wheel must travel at a higher rate of speed to perform a smooth turn. This is where the differential system comes into play. For four wheel drive vehicles, you really shouldn’t neglect the transfer case because it’s needed to engage the front differential in bad weather.  

Can you drive with bad differentials?

Technically yes, but we absolutely do not recommend you do. Driving with bad differentials can severely damage the entire drivetrain system. This would lead to one expensive repair! We don't want that for you.

Signs that your vehicle's differentials may be breaking down

• How long has it been since you had your differentials serviced? If you can't remember, or the answer is never, it's time to have them looked at by a licensed car technician. Aspen Hill Exxon recommends they be serviced at 60,000 miles for their first service, and then every 30,000-45,000 miles.
• Oil breaks down over time, and every part of the vehicle needs to be serviced. Differentials can sometimes leak oil when they're starting to go bad. Check for oil leaks where the differentials are located. Are you unsure where they are on your vehicle? Check your owner manual, or ask your technician the next time you're in the shop.
• Have you noticed increased vibrations and noises while you're driving?
• Loud noises are always an indication that something is wrong with your vehicle. If your vehicle's differentials have started to go bad, you may notice some loud clunking or grinding noises.
• When you turn the wheel of your vehicle do you notice any strange new noises?

We want to keep you safe while you're driving. If you are located near Silver Spring, Olney, Rockville, Gaithersburg, or North Potomac Maryland, give us a call. We would be more than happy to look over your vehicle for you.