However, a good rule of thumb for rear differential fluid changes in older vehicles, especially those used for towing or in harsher conditions, is every 30,000 to 50,000 miles, or every 2-3 years, whichever comes first. If the vehicle is primarily used for light-duty driving in mild conditions, you might stretch it to 60,000 miles, but that's pushing it.
Crucially: Check your owner's manual if you still have it. It will contain the most accurate information for your specific vehicle. If not, consulting a Ford dealership service department or a trusted mechanic is highly recommended to get a definitive answer based on your vehicle's actual use and conditions. Ignoring rear differential maintenance can lead to costly repairs.
