Is service type accounted for?

I have to admit it. It's not politically correct, but I sure do like my Chevy Suburban. It can haul my trailer, go off road and get dirty, plow through all but the craziest snow storms and do everything in style. I feel like the dealer who services it - AT Chevrolet in Sellersville, PA, and David Harnak, my service consultant - care about the vehicle and how I use and maintain it.

I'm also a stickler for doing my oil changes and am a Nervous Nelly when it comes to things that I hear or feel wrong with my Suburban.

I travel a good deal for my job and get to rent or be driven around in all kinds of vehicles in all kinds of environments. Two recent trips started me thinking.

The first trip was to Suriname, a small country in northeastern South America. Suriname is about 5 degrees above the equator, so it's hot and humid in the summer and less hot and humid in the winter.

With the exception of a road to a hydropower plant, the roads outside the capital, Paramaribo, were all dirt. With the heavy rainfall, there was a lot of mud and ruts. Instead of lights and stop signs, they use speed bumps. These are effective, but hard on vehicle chassis.

I signed up to visit the Amazon jungle during my day off. I was picked me up in an older Suburban and we happily bounced off to Brownsberg, about three hours from the city. Suburbans like a certain amount of abuse and so it was well suited to the job.

The second trip, a week later, was to Saudi Arabia. I was picked up in another Suburban - a newer one, and we drove the two hours between the Bahrain airport and into Saudi Arabia. The road was straight and the driving fast - but not furious.

In the winter, Al Khobar in Saudi Arabia (the home of international petroleum company Aramco) is cool. There was a fine grit blowing all around that irritated my eyes and throat. Summers there are beyond brutal, with temperatures well exceeding 125° F during the day.

In contrast, when I returned home (outside Philadelphia), we had more snow than we had in the last five years combined.

Such varied conditions for the same equipment.

Now if your fleet had to exist in such differing environments, how should your PM task list reflect this? Is the task list made to suit the environment, or is it generic - just designed to be followed blindly?

Vehicle usage is also a factor. What about wear and tear on a Suburban in an urban environment which might be used by a building inspector (daytime only) or by emergency first responders (24/7)? Both applications use Suburbans of the same make, model and year. One carries an inspector with a briefcase and the other, half a ton of equipment. One is driven sedately while the other is always on the way to a fire or some other catastrophe.

The 2010 Chevy Suburban Owner's Manual advises: “Because of all the different ways people use vehicles, maintenance needs vary. The vehicle might need more frequent checks and services. Please read the information under Scheduled Maintenance. To keep the vehicle in good condition, see your dealer.”

Presumably, the dealer would be intimately familiar with local conditions. Even Chevy says to modify the scheduled maintenance if needed.

Each environment and kind of service places different stresses on the machine. Think about all the places and seasons where your fleet operates. Even within the United States we have Death Valley, Duluth, MN, the Rocky Mountains and the Houston Ship Channel - environments with wildly different effects on machines.

Take a close look at what is actually breaking down in your fleet. Some of those breakdowns reflect special stresses imposed by the environment, usage and service intensity.

To see this effect, answer these questions:

Does the PM task list consider failure modes which actually appear on your repair order system? For example, cranking systems in cold environments?

Are the systems being stressed to failure even covered by your current PM?

Is the frequency of the task list appropriate, given the utilization of the unit? For example, a 24/7 unit sees a lot more use then a daytime-only one. If both have a 30-day PM frequency, one is over-PM'd or one is under-PM'd.

Are you performing PMs and still having failures on those systems? How can you include those failing systems into your PM task list for the future?

The answer to these questions should help make a difference in the failure rates, resulting in improved safety, lower cost of operation, reduced waste and happier customers.

Joel Levitt has trained over 6,000 maintenance leaders from over 3,000 organizations. Since 1980, he has been the president of Springfield Resources, a management consulting firm that services a variety of clients on a wide range of maintenance issues.