This may be the longest internet page address in the world...Shell Australia. http://www.shell.com/home/Framework?siteId=au-en&FC2=/au-en/html/iwgen/shell_for_motorists/oils_lubricants/zzz_lhn.html&FC3=/au-en/tailored/shell_for_motorists/oils_lubricants/heli x/tips/check_level_ga_1410.html Here is a page from Shell Canada: http://184.108.40.206/code/motoring/tips/maintanence.html Notice: If you are driving in Canada with a Shell oil, be sure to change it every 5,000 KM. If you are driving in Australia with a Shell oil, you can keep topping off unless you've gone 15,000 KM. I know there are different variables at work here (different oil standards, Canadian extreme cold etc.)...but I think the biggest factor is that Shell (and all the other companies for that matter) is pursuing a different business model in each of these 2 places. In Australia they sure don't seem to be playing on people's irrational fear of engine wear. The Australia page doesn't even say that you need to be running the synthetic Helix to go that far, and doesn't mention the dreaded "severe" driving conditions that everyone by default travels in, etc. I'm really starting to think that most things about motor oil are hooey!