As per some of the other comments, having had quite an interest in them when I lived in London in the early 80s, I did ask some of the drivers in the depots about mileage. Given what I was told, the buses would seem to cover about 50,000 per year, meaning they would have covered a million miles in twenty years. As many of them were in service for twice that number of years, it is quite possible that on average they will have covered well over one million miles, possibly some may have covered two million or slightly more.

As per one comment I would imagine they would easily have covered the distance to the moon and back 500,000 in ten years, let alone their total life cycles. As most of the buses had body and engine changes, it would be hard to say what if any components ever lasted for forty years. It would be. Interesting to know!

The original 9.6 litre AEC engine or Leyland 0600 were both very understressed for longevity. The AEC 590 produced peak power at 1,800rpm and maximum torque at 1,000rpm. Given the above, it is likely that this unit which was extremely well manufactured could easily achieve 1 million miles before major overhaul. Given that they were often overhauled several times a mileage of 2-3 million miles before the engine was beyond economic repair is quite likely.

As one comment stated, the Aldenham works was designed to allow complete interchangeability, meaning that engines and bodies moved around, as did axles and transmissions. The front engine design also allowed greater cooling in traffic with a very large radiator, and in general the design was an evolution of the RT with tried and tested design parameters, which again aided reliability and longevity.

The idea of a large understressed unit was perhaps best seen in another manufacturer Gardner, who again focused on lower rpm engines with high torque over a wide rev range. The company itself stated that 1 million miles before any major work was quite normal, so this again adds to the above comments for the very well engineered AEC units.

On a personal note it was sad to see so many have these units removed, and even worse that so many were sc***ped rather than sold.

they were always a joy to travel on in the 1980s when I lived in London, and I find the sound at tick over of the 590 very relaxing.

In the yard of the haulage firm where I work are two Routemaster buses, one built in 1963 and the other in 1966. The '66 bus belongs to my boss and has been fully restored. The '63 model belongs to a friend of his and could do with about 5 buckets of filler and at least the same quantity of paint. I've had the dubious privilege of driving the shiny one. I'm sure all previous RM drivers must now have Schwarzenegger-esque biceps from wrestling with the steering. As well as a flat head from the lack of dampers. And no hearing ability left whatsoever. This is one of the 40mph models - apparently a few examples built for the Gatwick run had a much higher final drive ratio and could exceed 60! - although I levelled out at around 34mph due to the incredible noise from the engine some 12" from my left elbow. They don't have odometers, so.. how many miles is a RM likely to have covered since it was built? I would guesstimate between 1-2 million, depending on the route, but surely someone will have a more accurate idea. Dave TD.

I agree with you about driving one. A friend had an RM (now sold it) and I was allowed to drive it, and it's not easy as you take the whole carriageway, with little leeway. A mini roundabout was an interesting experience too.