The Mini was challenged with the gearbox in the sump from a technical point of view. That it was brilliant there is no doubt. That it was durable depends on your experience. What has been written about the mini over time was that BMC/Leyland had to make plenty of repairs to the Mini under warranty and the most expensive or serious kind of warranty claim would be to the drivetrain with the gearbox and common sump arrangement for the engine, transmission and final drive.
If BMC/Leyland had the foresight to adapt to an end-on gearbox/powertrain arrangement as the Japanese Honda and all the other small front-wheel drive minis of the era, perhaps the original Mini might have fared better. BMC/Leyland did away with Hydrolastic and retreated to rubber cone springs mostly to save money. Hydrolastic in the larger cars was a wonderful ride such as the BMC 1100/1300 cars. While not many who drove Minis may agree, personally I found the Hydrolastic a comfortable ride. I was sorry to see it removed from the production cars.
Other improvements that should have been made after WW2 was the electrical system with the stupid 2 fuse system to protect half the circuits on one 35 amp fuse and the other half with another 35 amp fuse. That old Lucas ‘Prince of Darkness’ image and all the jokes that went along with the reality of old technology really did leave many drivers in the dark and cursing. If you are driving in foul weather and you lose one fuse, your panel lights for the gauges go dark, along with your blower motor for demisting and your turn signals – talk about driving blind, your wipers are also on the same circuit!
Now you can’t see through a rain or snowstorm with a windscreen being rained on or snowed on and have no idea what your gauges are reading. Not to mention defrosting the front glass won’t work and if it’s cold out, you aren’t getting any heat blown by the motor. The other circuit protects the horns and brights flasher and interior light. So it was all stupid to continue this right up through the final Austin America sold and manufactured in 1971 in the USA. I’m sure this was common to all cars no matter where produced and sold.
As a final thought, the idiosyncrasies associated with Sir Alex’s small front-wheel drive cars were addictive and something unique. The gearshift lever that bounced up and down in it’s rubber mountings according to engine torque when tromping down on the gas pedal or lifting it quickly. The whining of the gearbox, the throaty carburetors sucking air, and the booming of the exhaust. The steering and suspension gave the driving experience a wonderful feeling of control and the ability of a Mini or the BMC 1100/1300 had such precision in their ability to track accurately that it gave the feeling of a being in complete control at all times.
It’s a shame that events conspired to kill off the great qualities of these cars and the worst part of it is that no genuine breakthroughs in technology allowed these cars to continue as they were with technical improvements. It would have been fantastic to have a Honda-type of final drive or trans axle with the Cooper S engine.
Hondas don’t break their gearboxes and final drives like the old Sir Alec designs.