Top 10 Interchangeable parts

Some cars are literally greater than the sum of their parts. We look at some examples of parts-sharing, from the ones which could save you money to the ones which may just surprise you!

One of the thorny issues of keeping an old car on the road is the supply of parts. While some manufacturers are better than others, at some point the parts desk at your local dealer will struggle to provide parts for a car that’s 30, 20 or even 10 years old. And that’s assuming the manufacturer is even around any more! Motor factors and specialist suppliers can continue to supply parts from carefully-hoarded stocks or by going direct to the parts manufacturer rather than the car maker, but even this resource can sometimes run dry. And what if your classic never had much in the way of main dealer support, or existed only in small numbers?

There is also the problem of cost; the joys of depreciation mean that you can buy a classic car that was a seriously expensive and exclusive bit of kit when it was new for the price of a basic modern hatchback, but parts costs don’t depreciate along with the value of the car – keeping an exotic car going without a ready supply of parts can be crippling.

Fortunately it’s possible to source parts from all sorts of places thanks to the nature of the motor industry. Few, if any manufacturers, make all the parts of all their cars; they specialise in designing and making cars en masse but it’s not worth their time to design and build systems such as the brake, electrical, ignition and fuel systems.

Transmissions are another specialist field which many car makers prefer to buy in from a dedicated supplier. When choosing things such as brake pads, headlamps and bearings, and even quite significant parts such as road springs, a manufacturer will often arrive at a specification and then choose a part already available from an industrial supplier. Each manufacturer will give these parts their own part number and they’ll be sold in their own branded boxes and at their own price structure, but if you know the code that the company which actually made the component then you can source identical parts from any source. Aside from the original equipment suppliers, many car manufacturers will make use of their own ‘parts bin’ to save development and design costs.

Large organisations such as General Motors, Volkswagen and British Leyland reused large quantities of minor (and often not-so-minor) parts from the bottom to the top of their car ranges. Other cars developed via joint ventures or platform sharing can also find themselves fitted with parts from surprising origins.

And this is without delving into the myriad of low-volume sports car makers which are such as key part of the British motoring scene – the likes of TVR and Lotus lacked the resources to design an entire car from scratch but excelled at taking often-humdrum components from elsewhere and using them to dazzling effect. So this feature is a brief look at some of these most surprising (and, in some cases, most cost-effective) cases of cross-pollination.