What is A Differential and What Does It Do?
I’m sure a lot of you have been there before, you’re getting work done on your vehicle and someone says, “We need to change the differential oil,” and you may have no clue what they’re referring to. Or any other car lingo that is thrown your way. Well, we are here today to explain what a differential is, types of differentials, and caring for your differential.
Like most components of your vehicle, each hasve a specific task that helps keep your vehicle moving. A differential is part of the front and/or rear axle assembly. The axle is known to be the central shaft that the wheels rotate around. The differential allows wheels that are on the same axle to rotate at different speeds. This function provides proportional RPMs between the left and right wheels. If the inside tire rotates 15 RPM less while in a turn than going straight, then, the outside tire will then rotate 15 RPM more than going straight.
Think of when your vehicle is going around a corner, the wheel on the outside is traveling faster than the wheel on the inside. What is allowing this to happen is your differentials. Two-wheel drive vehicles have one axle and four-wheel drive vehicles have two.
Types of Differentials
Open Differential– this type is the oldest and most common design that is suitable for various makes and models of vehicles. It is the most reliable, simple, and widely used. The powered pinion gear, which is located at the end of the driveshaft, will engage with the ring gear, then transmits power to both axles through another set of gears.
The only flaw with the open design is that when one wheel begins to slip, all power is in the essence sent to the wheel with the least amount of traction, making this design unfit for rock climbing or high-speed racing.
Limited- Slip Differential– this type is similar to an open differential, but it utilizes an integrated clutch system. The clutch mechanism will lock the left and ride sides of the axle together when a wheel loses traction. This is the preferred design for high-performance vehicles.
Torque-Vectoring Differential– this is the latest and greatest in differential technology. Torque vectoring combines a complicated collection of sensors and electronics that obtain data from the steering system, throttle position, road surface, and more, allowing to distribute power to each wheel, according to the collected data. This design provides maximum traction while cornering which increases performance significantly.
How to Care for Differentials
Keeping up with regular maintenance for your vehicles is a must. Everything from oil changes, belts, hoses, and other fluids. The differential fluid is no exception. Differential oil is used to lubricate manual transmissions and differentials. Think of its importance similar to the oil for your engine. It plays a crucial role in protecting the differential and transmission, allowing them to run accordingly.
The differential oil becomes old, dirty, and contaminated after a period of time. If continued to drive on spent differential oil it can put unnecessary wear on components, leading to more serious damage. Some signs that you need to change your differential fluid and need service:
- A whirring noise only when decelerating
- A howl or whine during acceleration over large or small speeds
- Rumbling or whirring at speeds over 20 MPH but changes when turning
- Regular clunking sound every few feet when you first start to move
- Steady vibration that increases when speed increases
It’s a safe plan to have your differential fluid, or gear oil, changed every 30,000 mules and do not exceed 60,000 miles by a trained technician. Clean, fresh oil permits better protection of the differential leading to a safer ride. Your vehicle will not be able to go far without the ability to turn correctly. Lubricating fluid within your differentials transfer heat away from the gears that will extend its life and keep you on the road.