When you drive around around a corner, your outside wheels have to travel farther than the inside wheels. Sure, it may seem like a small amount of distance but that little bit adds up to a lot — and it can do damage to your vehicle if the difference isn't compensated for.
Your differential compensates for this difference in distance through a set of gears that transfer the torque mechanically. The main point of this is to keep the load on the engine and transmission steady no matter how sharp your vehicle turns.
The differential gets heavy loads put on it which can lead to increased heat and wear. That's why we cover it all in thick gear oil. It allows the parts to run smoother and reduce the overall friction.
It's a good idea to change differential fluid at least every 50,000 Km to 70,000 Km. If you're hauling heavy loads, we recommend even more frequent service appointments.
Sure, you can. But should you? Probably not. The fluid has to be disposed of properly, you might need new gaskets or seals, and the parts inside the differential housing have to be wiped down so that any contaminants from the old fluid aren’t transferred to the new. Honestly, it's a dirty job and if your home shop isn't set up right you're going to end up wasting time and probably making things worse.
When you bring your truck into Onsite Truck & Equipment Repair for driveline service, our technicians also diagnose any potential problems before they get out of hand. We'll often find leaks that lead to fluid loss and have prevented trucks from having huge maintenance and potential rebuild issues down the road.