A Seasonal Variation

Although it might make perfect sense, it only made perfect sense to me after it was pointed out to me by someone in the know. There is a seasonal variation to the demand of service parts for motor vehicles. Say what?

Well, let's back up a bit. The automotive parts suppliers make two kinds of parts. The first kind is called Production Parts. A car is designed, mocked up, prototyped, tested, tweaked and approved. It enters production. If the car is exotic, the production may be in the hundreds or thousands. If it has mass appeal, the production run may be in the tens of thousands or maybe even hundreds of thousands. For instance ... sales of the Toyota Camry in the United States peaked in 2006, with that nation’s most popular family sedan selling 448,445 units, according to http://most-popular.net/car-america. The production parts are trucked in from the parts manufacturers straight to the assembly plant, where the parts are used to build a brand new car. Some Camry stats for the curious: http://www.topspeed.com/cars/toyota/2006-toyota-camry-ar910.html . The production parts flow fairly consistently throughout the model year, perhaps the flow is a bit heavier in the beginning of the production year and a bit lighter near the end of the production year, but generally the production planners and schedulers have a pretty good idea of how many units need to be built and the work is scheduled accordingly. The two biggest factors affecting the the quantity of production parts shipped to the assembly plants are the popularity of the model and the general health of the economy.

Now comes the Service Parts. We don't hear too much about service parts but we surely expect them to be there. To further the example: assume you've bought that 2006 Camry, but it is now 2008. Someone at the mall backs into your car and takes off, leaving you with a nice ding. Off you go to the body shop for an estimate. Now depending on the extent of the damage, the ding may be worked out or the body panel or lighting assembly may need to be replaced. With what? That 2006 Camry is no longer being produced, so production parts are no longer available. Parts needed to replace or repair the damage do not get shipped in from the assembly plant. Those parts still come from the same people that made the production parts, but they are now called service parts and packaged and routed differently.

The number one source for service parts, reasonably enough, are the dealerships themselves. But, there are also secondary sources for service parts like Partsource, Napa, UAP, CarQuest. These are not the only sources for service parts, though, just some of the more popular ones.

I work at the General Motors National Parts Distribution Centre in Woodstock, Ontario. No production parts go there. Only service parts. The GM parts come in from the very same plants that made the production parts, but the these parts are destined for the GM dealerships and the collision and repair shops .

So where does the seasonal variation come in? Well ... what usually happens when that first flake of snow hits the pavement. The good people are still driving like it is summer out there and so off they go, sliding into each other and into the ditch. Reliably, the service parts industry gets busier in the winter and slows down in the summer.