Changed differential fluid for 25C$ at Rapidlube(Shell)now defunct (not making money,Station trying to get rezoning for doughnut shop on site) at 60,000 kms.

Since then,not one drop of leak since.Is there any reason to check level at anytime,if meticulous check almost wkly in own garage show no leak of any fluid whatsoever.Hate to crawl under car to encouter frozen nut etc when Sjell did it for 15 US $.

TOM

You can have lifetime fill with synthetic gear oil. No need to change unless somehow it gets contaminated.

Checking for leaks is always wise. No need to frequently check level...every quarter or so is problably fine considering MILLIONS of people rarely check any fluids!!

Anyhow differential leaks are typically at the pinion seal (obvious) and more commonly at the axle seals (hidden) and it's typically too late for the parking brake shoes once you find this stealth leak.

Checking the lube every 5k, as recommended, is a little overkill IF you practice good "driveway mechanics", i.e., you look closely at the parking spot every time you pull out. Any fluid leaks usually show up first under the car while it has been parked. If your pinion seal or rear axle bearings are leaking, they will show up with some drips. If this is the case, then check the lube at once and repair the leak, or you will need a new rear end. I also clean the area around the pinion seal so I can see leaking oil more easily (it tends to be thrown onto the body around and behind the seal.)