I owned a BA Falcon, which I used as a taxi for four years. I found the cure for a noisy diff was to change the oil and add Penrite Diff Additive. There was never a murmur after that. I can recall ...

Let's be honest, the average person has never thought about whether differentials even have fluid. They're not like engines, which require oil changes after about 5,000 to 10,000 miles (or 12,500 if ...