How often should differential fluid be changed? I've never heard the cats down at the local Jiffy Lube make any mention of even checking mine, much less having to change it. In fact, they seem to run the same checks on the rear-wheel drive vehicle that I have now as they did on my front-wheel car I had a couple of years ago.
That seems like something important to find out. I'll ask the Jiffy Lube guys the next time I'm in for an oil change.