April 28, 2019
Hello Fort Mill - let's talk differentials. If you have a rear-wheel drive vehicle, your differential is on the back axle. With front-wheel drive cars, the differential is up front. All-wheel drive and 4-wheel drive vehicles have three differentials - front, rear and in the middle. So you see, you've got a differential (or two or three) and it needs service now and then.
What does your vehicle differential do? Well, it compensates for the differences in speed between your outer and inner wheels in a turn. Using the dimensions of a typical car, let's compare the distance the wheels travel from the start of a turn through to the completion of the turn.
The inside wheel travels about 12.6 feet/3.8 meters. How much farther does the outside wheel travel? About 18.8 feet/5.7 meters – over 6 feet/1.9 meters more. This means the outer tire has to rotate 9 times in the same amount of time that the inner tire has to rotate only 6 times - so the outer tire has to spin faster in order to keep up. The differential makes this possible.
The gears in the differential are cooled and lubricated by differential fluid. It's this fluid that needs to be serviced. Small bits of the gears break off and are suspended in the differential fluid. The dirtier the fluid, the faster the gears wear.
So your Tuffy Charlotte Metro technician drains the old fluid out and replaces it with fresh fluid. Some differentials also need a special additive that is put in at this time.
So when should you have your vehicle differential serviced? Intervals vary from vehicle to vehicle – and may be as short as 15,000 miles/24,000 km – so check your vehicle owner's manual or ask us at Tuffy Charlotte Metro. If you frequently drive with heavy loads, tow a trailer or drive in hot SC conditions, you may need to change differential fluid more often. Servicing your differential on schedule at Tuffy Charlotte Metro can save a pricey replacement down the road.
Give us a call.
Tuffy Charlotte Metro
 9909 Charlotte Highway
 Fort Mill, SC 29715
 803-802-2466
 http://www.tuffyftmill.com

October 27, 2025
So you almost got through the winter until, one day, your muffler started sounding like a dragster, loud and obnoxious. It's not surprising. All that road salt and brine can cause rust to punch holes in a muffler, and that should raise a big, red warning flag about the safety of your vehicle. O... More

October 23, 2025
There's one fluid in your car you are always careful to keep at a certain level: the fuel. If you don't have fuel, you're not going anywhere. Your vehicle has other fluids which are vitally important to proper and safe operation, too. So, here's a "level" headed approach to those "other" fluids... More

October 12, 2025
When you're driving and turn a corner, you probably aren't aware of all that's going on with your wheels. The outside wheels have a longer distance to travel than the inside wheels, so there are gears that allow the wheels to go at different speeds when you turn. That set of gears is called a d... More