Maintaining good numbers

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Maintenance statistics yield information that you can use to improve cost management, productivity, warranty recovery, equipment selection and more. Produced in copious quantities by any of today’s maintenance software programs, maintenance statistics let you track vehicle cost per mile, component cost per mile, component failure rates, component failure rates by brand – any way you decide to crunch the numbers.

But if the information used to generate these statistics isn’t completely accurate, the output can be misleading and counterproductive. The conclusions that flow from analyzing these statistics are only as good as the information that goes in.

Getting the full picture
It may seem obvious, but it’s important to realize that there are several ways to look at a cost. How you choose to measure an expense item determines whether that item will be a major priority or a minor concern. Consider lighting. According to a survey conducted for the Technology and Maintenance Council of the American Trucking Associations, lighting failures in a typical fleet account for about 4 percent of parts and labor costs, as reported by repair orders – making them one of the lowest-cost items on a typical tractor-trailer combination.

The frequency of lighting-system repairs, however, is 15 percent of all repair orders generated – the highest of all vehicle systems. So, if you looked at direct cost, lighting would seem pretty harmless, when quite the opposite is true, considering vehicle availability and productivity. Every time a vehicle has to come into the shop to correct a lighting failure, that’s freight-hauling, revenue-producing time lost, which has a definite dollar value.

There’s also exposure to workers’ comp liability. Whenever a technician has to climb a ladder to replace a marker lamp, he’s at a much higher risk of a fall injury.
Chad Johnson, vice president of maintenance, Ruan Transportation Management Systems, Des Moines, Iowa, took all lighting-system failure costs into account and started spec’ing longer-lasting LED lighting, even though it’s initially much more expensive than incandescent. “We tracked all lighting-related costs,” he says. “You’d be surprised at what we found. We’re also doing some work with wiring harnesses.”

In short, the more real-world factors you can input into your maintenance system, the more meaningful the results will be.

Apples to apples
It’s important to remember that one batch of statistics is meaningless. Statistics reports have to be repeated, over a period of time, to establish benchmarks for whatever you want to watch.

One way to ensure that statistics are kept consistently is by using the newest version of TMC’s Vehicle Maintenance Reporting Standards – VMRS 2000.

VMRS has been the trucking industry’s universal coding convention since 1970, when it was created under the auspices of the ATA. Now managed by TMC, VMRS 2000 is more than just a universal parts numbering system, according to Robert Braswell, TMC’s technical director.
VMRS is the trucking industry’s common shorthand for equipment maintenance reporting. It alpha-numerically represents, in just a few keystrokes, every aspect of the vehicle maintenance process. And that’s what makes it highly interesting to information specialists who develop the latest generation of maintenance software packages, computer-based training tools and e-commerce processes.

VMRS consists of 56 datasets or “Code Keys” that include up to thousands of codes that simplify and standardize maintenance reporting. These Code Keys are used in various combinations, called “Instruction Sets,” that describe how a vehicle is specified, and what has happened to it during its service life.

“Think of VMRS Code Keys like words,” Braswell says. “Individually, they mean little. But assembled into sentences, they become very powerful tools.”

Here’s an example. Let’s say you wanted a way to describe, in just six characters, what a vehicle is; what a vehicle does; and what special body features a vehicle has. You can do it with VMRS 2000’s Instruction Set 14, which uses VMRS Code Keys 1, 2 and 48.

1-22-185, for example, tells us we’re looking at a truck, in pickup and delivery, refrigerated service, equipped with a special walk-in refrigerated van. 1 = truck (straight), from Code Key 2, “Equipment Category.” 22 = P&D, refrigerated, from Code Key 1, “Equipment Vocation.” 185 = special walk-in refrigerated van, from Code Key 48, “Special Body Type.”
Here’s another example. Let’s say you wanted to describe a brake lining replacement during preventive maintenance. Here’s how its done in just 13 characters – 013-001-015 03 08.

The first nine digits describe the component involved:

  • The first three digits, 013, tell us its brakes (system);
  • The next three digits, 001, tell us its the front brakes and drums (assembly);
  • The last three digits, 015, tell us its the front brake lining (component).
  • Following the component code, the next two digits, 03, tell us the work accomplished – in this case, the technician replaced the old part with a new part.
  • The last two digits, 08, tell us the reason for repair – in this case, preventive maintenance.

Alternately, you could identify the part manufacturer using the five-character Code Key 34 and describe the replaced part’s condition using the two-character Code Key 18, Technician Failure Code.

“These series of standardized fields and codes may not be immediately impressive to us humans, but computers love this stuff,” Braswell says. “VMRS is their kind of language.” VMRS allows software to describe equipment-related work easily and in a consistent manner – something that conventional human languages, like English, can’t do easily. Consider something as simple as a thermostat. Manufacturers use six different terms (and who knows how many part numbers?) among themselves to name this part. VMRS can do it in just nine numbers.
David Foster, director of maintenance, Southeastern Freight Lines, Columbia, S.C., says VMRS plays an important part in his company’s maintenance tracking, replacement parts purchasing and vehicle acquisition processes.

Thanks to VMRS and diligent monitoring, Southeastern has been able to reduce inventory turns, lower inventory totals and better understand what systems require the most attention. VMRS also helps them establish labor benchmarks and improve warranty collection, according to Foster.

Using accurate, consistent data collection, there’s practically no limit to the number of reports you can generate. But, despite the sheer volume, “It’s pretty easy to tell when something’s wrong,” says Ruan’s Johnson. “I can look at 100 charts in a few minutes and tell you what’s out of line.”

When Lew Flowers, vehicle maintenance manager for the U.S. Postal Service in Oklahoma City, decided to analyze road-call reports, he noticed a high percentage of afternoon no-starts. He reviewed electrical-system maintenance procedures but found that “the technicians were doing everything right.”

Suspecting that a high number of morning shut-offs and restarts might be more than the vehicles’ batteries could handle, he began fitting higher-reserve capacity batteries. Then, to be sure, he continued to scrutinize road-call reports and found that no-starts had dropped dramatically.

Pushing the envelope
Even when monitored components or processes seem to be normal over a given period of time, you may decide that the benchmark can be improved. For example, “We wanted to lower our on-road, tire-failure rate,” Johnson says. “So, we put a limit on how long we would run a casing. That immediately lowered the failure rate.

Recently, we raised that limit a little, and we’re still watching to see what happens. You have to look at averages and trends, then watch for a significant change.” The idea in this case is to fine-tune the system and find a happy medium between the cost of tire failure and the cost benefit of extending casing life.

There seems to be no question that paying careful attention to tire costs – the No. 1 cost item in a typical fleet’s maintenance budget – pays big dividends. When Charles Arsenault of Arsenault Associates in Atco, N.J., conducted a cost analysis for two fleets with similar size and vocation, he found that one fleet’s tire cost per mile was twice the other’s. The difference? The fleet with the higher cost per mile only had a tire-repair program in place. The other had a comprehensive tire-maintenance program.

Ruan’s decision to change its PM intervals is a good example of using maintenance statistics analysis to increase productivity. Ruan had been conducting PMs based on time and miles. The company had extended its engine oil drain intervals and started doing a mid-point PM (a dry PM where everything is greased and inspected). After looking at several years of data conducting PMs on this schedule, Johnson saw that the mid-point PMs were taking nearly as long as the full PMs. Furthermore, Ruan mechanics were now inspecting trucks six times per year on average, when they had previously looked at them only four times per year.

From this data, Ruan decided to schedule PM intervals using a time-only constraint, with an upper control limit for miles. Ruan’s service facilities now conduct PMs on 60-, 90-, or 120-day intervals – depending on equipment and application – but they won’t go beyond the mile limit Ruan has issued. Due to these changes, Ruan was able to reduce the number of PMs conducted, which decreased vehicle downtime and reduced maintenance expenses.

“The beauty with using a time-only PM schedule is that we can sit down with a calendar and tell our customers when each truck will need to be maintained,” says Johnson. “With this system, we can tailor PM intervals to our customers’ needs.”

As Ruan learned, statistics aren’t just about finding problems. They are about improving on results. Maintenance statistics won’t always serve as warning lights. Sometimes they are more about raising the bar.

VMRS 2000 at a glance

VMRS 2000 is the latest version of TMC’s Vehicle Maintenance Reporting Standards coding convention, established more than 25 years ago. VMRS 2000 represents a significant step forward in the evolution of VMRS.
Based on user requests, TMC has:

  • Increased the capacity of Code Key 33 to track vehicle systems by adding a ninth digit to the basic eight-digit code. VMRS can now accommodate growth for up to 1,000 distinct vehicle systems – a 900 percent increase from the original 100.
  • Reviewed Code Key 33 thoroughly for inconsistencies in coding, language
    and descriptions, etc., to ensure consistent use of the coding convention, industry-wide.
  • Revised Code Key 34, which identifies manufacturers, suppliers and brands. The new Code Key 34 is based on the Dun and Bradstreet “DUNS Number,” an internationally recognized, corporate identifier. VMRS 2000 retains the five-character alpha manufacturer’s code used since 1970 and preferred by most fleets. But the new, nine-digit identifier allows companies to identify parent-subsidiary relationships and obtain vital statistics on the organizations contained within Code Key 34.
  • Expanded Code Keys 1, 2, 10 and 48, which describe equipment categories, vocations and body types. These codes now accommodate many industries beyond trucking, such as transit, off-highway and construction.
  • Added Position Codes. Code Key 79 allows VMRS users to identify position, based on industry-accepted conventions.
  • Added warranty-related Code Keys, such as Code Key 81: Type of Claim.
  • Improved the VMRS Implementation Handbook, by upgrading text and graphics and making available a completely electronic version of VMRS for easy integration into existing computer systems.
  • Established a VMRS 2000 licensing program to encourage consistent industry use of VMRS.