Originally Posted by Fahrer

Car manufactures almost always make the body-in-white There are exceptions as the Cayenne was originally produced at the VW plant in Slovakia that produced the Touareg as well ( even Before VW took over Porsche). Most of the time the car manufacturer make the engine as well but not always. Transmissions are only sometimes made by the car company. If you have a 6 speed manual, your transmission was produced by Aisin which is owned by Toyota. The 8HP 8 speed trans found in the Audi A6 and the BMW 5 series are the same and come from the same manufacturer, ZF. The early Boxsters were largely produced by Valmet, the Finnish weapons manufacturer. The Porsche 924 and 944 were made by Audi for Porsche. Magna produces cars for different manufacturers under contract. Things like braking systems., turbos, fuel systems, all electronics, suspension pieces, bushings, glass, seats,and on and on, are produced by global suppliers who focus on these things. The wonderful seats in 911 and the traditionally crappy seats found in the Corvette are made by the same company. Each of those suppliers will make anything the OEM wants at an agreed price. The quality can be at any level the OEM chooses for that model. Generally, there are one or two suppliers approved for smaller items, one supplier for major items.

Originally Posted by MaximumA

I was curious about your reference to Valmet as a Finnish weapons maker, so I checked. As far as I know, it is Patria which makes armoured vehicles and such. Valmet Automotive was established in 1968 and assembled Boxsters in the past. It currently makes Mercedes Benz A class and GLCs as a contract manufacturer. It also does engineering and has some expertise in e-drives and battery technology. And it makes convertible hoods and active spoilers as an OEM. I wonder who for.

Valmet (another company, same name) offers automation and other technology to the pulp, paper and energy sectors, and has a whole portfolio of other products incluing biofuel, chemical, pharma, food, biotech. It lists rifles as part of its "historical products" (namely hunting rifles and assault rifles). I'm guessing you're a hunter?

Anyway, I'd agree that it is a rare firm that makes its all own floorplans/bodyshells, engine, and gearbox. Most of it is bought in and assembled. And there are endless suppliers to the suppliers. The airbags for example in my the OEM fitment Recaro seats (as installed at the factory in my other car) were made by Takata (until a while ago...).

Originally Posted by Balr14

Back in the old days when I used to build cars (60s & 70s), we used Jaguar independent rear suspension a lot. It looked cool, was readily available and cheap because parts were very expensive and hard to find, so nobody wanted them. Most people didn't know the parts that needed replacing were made by Ford and used in the F150 pickup truck. A bearing set that Jaguar listed for over $200 and took a month to get could be bought off the shelf at a Ford dealer for $11.