Right-sizing vehicles

More model choices are leading fleets to smarter vehicle size decisions


With the diverse range of light and medium duty truck models being produced these days, fleets no longer have to buy a one-size-fits-all vehicle for their business needs. Rather, they are right-sizing to a particular vehicle class to try and squeeze greater savings from their fleet operations. In many cases, this has meant dropping down in gross vehicle weight rating.

To gain some insight into this growing trend, Fleet Maintenance Magazine editor David A. Kolman spoke with Robert Johnson, fleet relations director for the National Truck Equipment Association (NTEA). Based in Farmington, MI, NTEA is the premier association supporting the commercial truck and transportation equipment industry.

Fleet Maintenance: It wasn't that long ago that truck manufacturers didn't offer many Class 4 and 5 models. Consequently, fleets had to overload their Class 3 trucks or step up to Class 6 models, typically resulting in extra operational and maintenance costs and reduced vehicle life. Can you elaborate on this?

Robert Johnson: Going back to the 1960s and early 1970s, Class 4 and 5 chassis were available from a number of OEMs. When these went away, some fleets upgraded to Class 6 trucks, using the logic that the extra purchase cost would be offset by lower maintenance.

Unfortunately, many of the fleets that upgraded did not factor in the higher operating costs that result from reduced fuel economy and more expensive routine maintenance costs (tires, brakes, suspension parts, etc.). Also, in some cases, there was no increase in service life since many vocational applications are low mileage and vehicles are typically replaced on the basis of body condition (rust, etc.) as opposed to mechanical condition.

The fleets that went the other direction and downsized to Class 3 trucks frequently found themselves facing issues such as broken frames, excessive suspension and brake wear and premature powertrain failures due to overloading.

A number of fleets I am familiar with first downsized and then upgraded to Class 6 trucks due to excessive maintenance problems. Those that did not upgrade were quick to jump on the "super duty" chassis when they first came out, but many of those who had previously upgraded were hesitant to downgrade again due to their previous experiences with Class 3 chassis.

FM: Regardless of vehicle class, isn't the key to vehicle performance, durability, life and lifecycle savings to properly spec the vehicle for the intended application?
RJ: Yes indeed. It is critical that a truck be properly matched to the application. This means that no chassis component is overloaded and that the powertrain is adequate to provide the desired level of vehicle performance.

On the other hand, if you over spec components, you are going to incur an increased first cost and may also find that your routine maintenance and operating costs are greater than expected.

I present a number of seminars through the NTEA which specifically address this topic.

FM: When did vehicle manufacturers truly begin addressing this situation by expanding their portfolio of Class 4 and 5 products?
RJ: The first of the modern era Class 4 chassis appeared around 1989 and there has been a gradual expansion of availability since that time.

Originally the only Class 4s available were 60- and 84-inch CA (distance from the back of a truck cab to the center line of the rear axle) chassis cabs. But in recent years we have seen this expand to include vans, cutaway and stripped chassis in both the Class 4 and Class 5 categories and in multiple wheelbases.

At the same time, we have seen downgraded versions of Class 6 chassis slip down into the upper limits of Class 5.

FM: Why do you think it took commercial truck manufacturers so long to realize there was a void in their product lineups?
RJ: I think part of the issue was a hesitation by some OEMs to cut into their existing sales of Class 6 chassis. In addition, I think that upfitters and end users were able to work successfully enough with what was available that the need for intermediate chassis was not clearly evident to the OEMs.

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