Form, Fit and Function

Form, Fit and Function

What do technicians want in the parts they source? The answer is easy: fit, form and function. Are you giving them what they want?

Why do professional technicians choose one line of parts over another? That question might be one of the eternal mysteries of the parts distribution universe, especially for an ad department trying to devise an effective marketing plan.

Most technicians base their choice on three major qualities: form, fit and function. Form, fit and function define the technician’s mission of restoring a vehicle’s performance to "like-new" status. With that said, it’s important to understand replacement parts are but one ingredient in the final mix we call an automotive repair.

To illustrate, the success of a $3,000 engine replacement can hinge upon the form, fit, and function of a $10 replacement thermostat. If the thermostat sticks closed, the engine will suffer damage from overheating. Consequently, an experienced technician isn’t likely to select a brand of thermostat based on price or promotional perks. Instead, he’ll select a product that makes his professional life a little easier through the attributes of form, fit and function. To better understand what form, fit and function mean, let’s delve a little deeper into the psychology of the professional installer.

Form is a vague word that can be highly subjective in both meaning and application. In my book, form is the quality that first attracts the attention of the professional technician. To better understand form, let’s start with packaging (Yes, the box can be as important as the part in the minds of many pro installers).

In this age, the packaging of the part can be as important as the part itself. The packaging of a remanufactured engine control module (ECM) is a good example because the packaging of the part itself has a direct affect on the part’s reliability. Most quality reman ECMs are sold in a sturdy cardboard carton that has a secure top and bottom. Once the carton is opened, the technician sees that the ECM is wrapped in a moisture-resistant layer of plastic and is insulated from vibration damage by cardboard or Styrofoam retainers that prevent damage caused by careless shipping and handling.

Proper documentation is also important to the professional technician. Although the professional technician might consider an enclosed set of instructions as optional reading, he still considers the presence of installation instructions as an extremely important issue because the ECM may require some special installation techniques, such as reprogramming for the vehicle application.

Warranty documents are also important, especially those that require vehicle applications and mileage. In addition to vehicle information, the warranty document may also ask why the ECM is being replaced. This is important to the professional technician because the ECM core may have an intermittent condition that should be addressed by the remanufacturing facility before it can be repackaged and sold elsewhere. The fact that the remanufacturer is asking for this information is a type of quality guarantee highly valued by the true professional technician.

Of course, we can’t forget the form of the part itself. A true quality part exhibits its apparent quality in its craftsmanship and finish. Quality parts exhibit a luster that communicates care and pride in manufacture. In contrast, the lack of finish on cheap parts lack communicates a certain haste and lack of quality control during manufacture. In short, the fact that form communicates the overall worthiness of the part to the professional installer is something that suppliers should take into consideration.

The three-letter word "fit" is self-explanatory. If a replacement part doesn’t fit the application, the professional installer can’t install the part.

To better illustrate, many years ago, one of my local jobbers began supplying mechanical fuel pumps that required some adaptation to make them fit various applications. On paper, the fact that a fuel pump outlet was fifteen degrees removed from the OE location didn’t seem consequential. After all, by moving the outlet fifteen degrees, the manufacturer could make the pump fit, for example, 50 percent more applications. In real life, however, the installer was faced with an extra 30 minutes installation time in fabricating new metal fuel lines to install this so-called "universal" fuel pump. Obviously, the extra labor required to install the pump out-weighed its initial cost savings.

The same can be said of brake pads and shoes made with extra-thick linings that make them difficult to install on new rotors and drums. Or, the same can be said of alternator belts that require a high range of adjustment. Or, of mufflers that are a little too long or short for a specific application. Whatever the case, the lack of precision fit creates current and future difficulties for the professional installer. As the old saying goes, "once burned, twice learned."

Now that the part is installed, how well does it function? Function or performance is obviously the core attribute of any replacement part.

Sometimes, the part may perform well in the short-term, but fail in the long-term. To better illustrate, an inexpensive air filter might seem to perform as well as its more expensive counterpart. But, the inexpensive air filter might also shed small paper fibers that accumulate on the hot filament of a mass air flow sensor, which causes the air flow sensor to miscalculate the volume of air flowing into the engine. This miscalculation, in turn, causes fuel trim miscalculations within the vehicle’s engine computer that might also cause the less-experienced technician to perform unneeded and very expensive services, such as replacing fuel pumps and fuel injectors.

Brake friction lining is also another function-intensive component that is highly susceptible to performance-related complaints. Unlike many other replacement parts, brake linings are designed for specific markets and needs. Quiet operation, for example, isn’t as important in the heavy-duty truck market as it is in the luxury automobile market. Similarly, stopping power may be far more important to the performance and heavy-duty markets than it is to the standard passenger car market. Of course, longevity is important to all three markets, but is often secondary to quiet operation and stopping power.

In addition, the ability of a replacement part to function accurately in a variety of extreme environments is extremely important in all modern vehicle electronics parts. An oxygen sensor that is only one-tenth of a volt out of specification on its return signal may cause fuel trim issues to appear in the vehicle’s computerized fuel management system. The same can be said of a fuel pressure regulator that’s regulating fuel line pressure two or three pounds per square inch below specification. Or, the same can be said of an engine coolant temperature sensor that reads ten degrees higher in temperature than it should.

Last, the ability of a replacement part to operate at least as long as the original equipment part is perhaps the most important part of component function. Far beyond the question of price and availability, component durability is a question of the credibility of the technician himself. Because the technician stakes his own credibility on his choice of replacement parts, he’s not likely to choose parts that will cause him expensive comebacks that might cause his customer to question his professional ability, especially for the long term.

Clearly, form, fit and function are important qualities in any replacement part. Without them, the snappy ad copy and promotional perks associated with many replacement parts have less meaning in a more technically complex and performance-driven automotive service market. Given the fact that many modern vehicles are now being driven more than 300,000 miles without major repairs, the form, fit and function of any replacement part has become more important than ever before.

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