Time for Differential Service at Auto Pro Troy?
February 12, 2023
Hello Troy - 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 Auto Pro Troy 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 Auto Pro Troy. If you frequently drive with heavy loads, tow a trailer or drive in hot Michigan conditions, you may need to change differential fluid more often. Servicing your differential on schedule at Auto Pro Troy can save a pricey replacement down the road.
Give us a call.
Auto Pro Troy
512 East Maple Rd.
Troy, Michigan 48083
248-270-3002
Need Service?
More articles from Auto Pro Troy Auto Repair
Your Vehicle Is NOT Maintenance Free, Troy Car Owners
April 26, 2026
A generation ago, Troy drivers seemed to be more inclined to keep their vehicle's preventive maintenance on schedule. One reason for this may be that vehicles back then were a lot less reliable than they are today. Taking your vehicle in to your Troy shop every year or two for repairs seemed to... More
Automotive Tips from Auto Pro Troy: Making a Battery Last Longer
April 19, 2026
One thing all Troy drivers can do to extend the life of their battery is to keep it clean. A greasy, dirty battery holds in damaging heat. Same goes for removing corrosion from the terminals. Auto Pro Troy can help maintain your battery.Allowing your battery to be deeply depleted like from using... More
Why Alignment Matters (Vehicle Alignment Maintenance)
April 15, 2026
It's one of those things that can happen on a multi-day road adventure or a quick trip to the grocery store. You hit a pothole, go too fast over a speed bump, nail a curb. When it happens, you think, "I wonder if that was hard enough to do any damage?" But things seem ok and you continue on yo... More