Back to all

The Car Fluid Most Drivers Forget—And Why It Matters

August 9, 2026

Here’s an automotive part you might not be familiar with—the differential.  It’s a component that transfers power from the driveshaft to the wheels.  It’s called a differential because the left and right drive wheels travel at different speeds when you make a turn. During that turn, the wheel on the outside travels farther than the one on the inside, so the outside wheel is turning faster. 

Your vehicle’s differential works by having gears that regulate the whole process.  It has fluid inside to reduce friction between the gears. As you can imagine, those gears have a heavy load to handle, so this differential fluid helps reduce friction between the metal parts as they’re moving.  The fluid also carries heat away from the gears to keep temperatures down in the differential.

After a time, the heat and the loads take their toll on the differential fluid.  It starts to accumulate little metal particles from the gears wearing down.  After a while, your differential fluid isn’t as efficient in cooling and lubricating the gears.  The gears start making noise, aren’t as smooth as before and can reduce your fuel economy.  Let the fluid stay in too long and you can wind up having to replace the differential itself, an expensive repair.

The best way to make your differential last as long as possible is by having the differential fluid changed at intervals recommended by your vehicle’s manufacturer.  Your differential will not only last longer, it will make for smoother operation. It’s especially important if you use your vehicle for towing or do a lot of driving in stop and go traffic.  

It’s a fluid many drivers forget about, but maintaining your differential fluid will pay off in the long run. 

TLC Custom Exhaust Brakes & Tires
1735 N Main St
Royal Oak, Michigan 48067
248-541-8300
www.tlcautocareroyaloak.com

Need Service?

More articles from TLC Auto Care

Ready, Set, COLD! (Getting Vehicle Ready for Winter)

October 23, 2026

When the temperatures plunge, your vehicle better be ready because it faces a whole new set of challenges. Rubber stiffens, glass fogs, fluids freeze. Just thinking about it can get your heart beating faster. So here are some tips for getting ready for those inevitable colder temperatures. Ma... More

Why Timing Belt Maintenance Can Save Your Engine

October 11, 2026

One part of your vehicle you probably never think of is the timing belt. It coordinates the rotation of the crankshaft (which converts the up and down motion of the pistons into rotation motion) and the camshaft (which opens and closes your engines valves). Its vital that the timing of these mov... More

Why is Air Not Coming Out of My Vents?

October 4, 2026

You climb inside your vehicle, start the ignition, and reach for the fan control for the heating or air conditioning. But when you try to crank it up, no air comes out of the vents. It can make for a very uncomfortable trip, whether its hot or cold outside. Its important for the comfort of you a... More