Oils for older engines

Q. My pride and joy GQ just clocked up 300,000km. I’m pretty happy because about 280,000km have been mine – I purchased it a year old back in 1993 and it’s run like clockwork ever since. Aside from the usual maintenance I’ve never had to do any work on it. I’ve been running it on the recommended oil up until now (15W40), but I’m wondering whether I should run one of the oils that reckon they’re designed for older engines? What’s your experience with these oils, I’ve heard that all they do are, is thicker oil that only slows the engine down and makes it work harder?

A. Your GQ is half way to where our GQ is at 500,000km. As boring as it is I would just keep doing what you have been doing for this length of time already. My view is that thick oils take longer to get to all the little areas. I would be guessing your engine isn’t using oil if barely a little so again stick with what you have been doing. Those extra thick oils are probably trying to achieve something but its more a ‘stop-gap’ measure to the inevitable of an engine using lots of oil. By then you should already be thinking of a rebuild. In your case that might be at 800,00km