Since this was Toyoda's first production vehicle at the loom works factory, there were still many problems to be solved. When the first production examples were driven to Tokyo for the motor show, they were packed with many spare parts. These spare parts were in case something broke during the trip - luckily only a few replacement parts were required. Early sales were mostly to people who were sympathetic to local manufacturers and who were willing to endure many failures. To support them, design engineers from the factory were often sent to do repairs in order to learn which parts needed the most attention. For example, broken rear axle housings were common until new welding methods were developed. Repairs were done for free and sometimes entire trucks were replaced for free. Rectifications were then applied as running changes on the production line, reflecting Toyota's "5 Whys" problem solving philosophy.