Time for Differential Service at Charlie's Fast Lube Anna?
August 1, 2021
Hello Anna - 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 Charlie's Fast Lube Anna 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 Charlie's Fast Lube Anna. If you frequently drive with heavy loads, tow a trailer or drive in hot Illinois conditions, you may need to change differential fluid more often. Servicing your differential on schedule at Charlie's Fast Lube Anna can save a pricey replacement down the road.
Give us a call.
Charlie's Fast Lube Anna
1215 East Vienna St.
Anna, Illinois 62906
618-833-4999
http://www.charliesfastlubeanna.com
Need Service?
More articles from Charlie's Fast Lube Anna

Road Trip? Check! (Trip Inspection)
October 12, 2025
After months of postponing travel far away from home, a lot of us can't wait to hit the road and scream "Road Trip!" again. But how long has it been since the vehicle you're planning on taking has had a thorough inspection? And is it roadworthy for several days on the highway? Time to schedule a... More

Muffler: Victim of Winter (Muffler Repair)
October 5, 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

Beware of Potholes! (Avoiding Pothole Damage)
September 28, 2025
You may live in a region where roads become pockmarked with craters known better as potholes. They're caused by moisture seeping through a compromised road surface that can freeze, expand and literally punch holes in the road. And when your vehicle hits one of those holes that's big enough, the... More