How to keep your differential lasting a long time, with proper break in procedure. Just like all moving parts in an automobile, differentials can take time to properly mesh and soften any sharp spots as the gears rotate. If you've recently installed a new differential in your car, this video provides tips on some of the things you shouldn't do, as well as what you should do, to improve the life of your differential.
Generally speaking, you'll want to go fairly easy on the car for the first 500 miles, avoiding things like long trips and towing, as well as aggressive driving. After 500 miles, be sure to drain the oil and exchange it for fresh oil. For more tips on keeping your differential healthy, as well as information about what oil viscosity you should be using, check out the video.