Michelin designed the PLR (Poids Lourd Rapide, or fast semi truck) in 1972 as a way to test out truck tires at high speeds without taking the the risk of using an actual truck. The general idea was that if a tire blew out, the engineers didn’t have to worry about losing control of their vehicle.
Nicknamed “milles-pattes”, or “centipede” in French, the PLR borrowed a lot of parts from the Citroën parts bin. This was not as random of a choice as it seems: Michelin owned Citroën at the time so it had easy access to the parts bin. The vehicle’s ten wheels and hubs came from a Citroën H van and a good part of the bodywork was borrowed from the DS Safari.
Michelin’s engineers fitted two Chevrolet 350 V8 engines in the back of the PLR. One drove the car and the other drove a mid-mounted truck wheel that was fitted with a test tire. The rear six wheels powered the car while the front four steered it, creating a complex but effective setup.
According to period Michelin records, the PLR had a top speed of approximately 180 kilometers per hour (111 miles per hour), which was not bad at all for a vehicle that weighed about ten metric tons.