How much of the car do the manufacturers actually make?

[DaBigGinger]

I was wondering, how much of our cars do the manufacturers actually make? For example, VW will carry out the final assembly of the car and paint it. But companies like Bosch provide the electronics, another company will make the shocks, another company will make the nuts, bolts etc.

Do many car companies actually make any of the raw parts? Even the panels or engines? Or do other businesses simply build what the car manufacturers design?

Then, I got wondering, how many parts are shared across other brands? Obviously, VW/Audi/Seat/Skoda will share a number of common parts. But, how many of the parts in our cars would we find somewhere else such as BMW etc?

[Yoof]

Interesting question! There’s a few of us that work in the industry on here, so no doubt you’ll get some informed answers.

Firstly, it entirely depends on the end product, volume, and OEM building it. I’ll give an example using an engine block (most cars have them):

Low volume (let’s say sub 10,000 vehicles/annum) aren’t going to purchase a foundry, and tool up to manufacture <10k blocks a year, financially it doesn’t work. So they will buy capacity from a supplier (Grainger & Worrall for example). GW as a component supplier, are then contracted to provide ‘x’ number of engine blocks to OEM timing/quality etc.

The reverse of that is a high volume player, with global product presence, component shared across platforms, big boy stuff. This is when you might well find Ford/Volkswagen own a supplier/foundry so they have complete control over the manufacturing chain.

Clearly an engine block is bespoke to individual OEMs. But, what about something like an indicator blub, or a map sensor? Generic components are often much cheaper to be purchased from a supplier, as they have ultimate economies of scale.

But, clearly the manufacturing process is a very small part of the bigger picture. OEMs control every part of the process; right from initial design, development, manufacture, integration, calibration, type approval, assembly etc. That excludes the interesting bits like research, concept development and advanced engineering, or the customer facing roles like dealerships.

So, to answer your question:

OEMs may make some of the raw parts, depends on the OEM, and what the part is. A Bentley seat for example is stitched together on site, clearly they don’t breed and manage cows for the leather directly.

Other businesses often build components of sub-assemblies. The exception to this is probably powertrains, where whole assemblies are purchased from gearbox suppliers (ZF for example, are in Jag, Bentley, BMW, Audi etc)

Regarding sharing across brand, in the scheme of things probably quite a small percentage of parts. A gearbox is a good example, ZF make the 8-speed box popular in any premium car for the last 3 years. OEM engineers integrate and calibrate this. So although your BMW shares the same box with an Audi, it can behave and drive completely differently (brand DNA).

Interesting subject, but very dependent on which component you’re asking about, and which OEM!

[DaBigGinger]

Cool, thanks for the input, Pete

[Jezza-7]

Im an aircraft engineer and the aircraft are similar in what the manufacture actually makes.

The Westlands Seaking, based on the sikorsky seaking (usa built), don’t really make a lot of the aircraft components that it uses. Apart from the airframe construction (although some parts such as stringers may actually be made by a manufacturer), painting and build line, not much much is actually built and made by westlands. They do make some of the larger components such as main and tail rotor blades, gearboxes, transmission, rotor heads but the engines and electrical side of things, i don’t think they make anything except wiring looms as they are all made on site on the build line, i believe. The electrical components are made by so many companies its crazy, even the engines built by rolls-royce have loads of components that they don’t even make. Garrett and honeywell are probably the biggest that are used.

Also quite a few components are used by various aircraft, the apache actually uses some parts from our sea kings, although they were both built from late 60’s to 70’s. And the apache uses the same engine that the merlin has.

One big difference from aircraft and cars is that all parts have to be OEM and we don’t use different suppliers for certain things, such as nuts, bolts etc. Biggest pain is that all the bolt and nut sizes are imperial so i can’t use them on the car!

[DaBigGinger]

I suppose the more you think of it, a lot of components for many things are probably made by multiple companies. Taking your aircraft example, I know Airbus parts come from all over the world. I know Rolls Royce and GE make a lot of aircraft engines, but I'm sure there are others.

Looking at computers, most parts are built by companies like Intel and Foxconn etc.

It's something I've never really considered that much until recently. I suppose it's something most of us just take for granted!

[woody02]

I work for Rolls-Royce on the engine build line (aerospace) and I'd say 70% of our engine parts and modules are made/assembled by different companies from all over the world, 15 years ago I'd say 70% of engine parts were uk manufactured.  Quite sad, lost lots of skills and loads of blokes made redundant over the years

[Jezza-7]

You work at the bristol Rolls_Royce? Went there last year and was interesting.

[woody02]

No mate, I'm at Derby, Civil engines. Bristol is the military side of rr.   Never been, wouldn't mind a visit myself.