“Nitrogen is saving us money,” he goes on. “Some of our fleet has nitrogen in the tires now, and we’re talking about 100 percent fleet on nitrogen fill down the road. With the high temperature fluctuations, the diurnal temperature changes, we could gain up to 40 pounds of tire pressure just from heat. When you’ve got a tire that’s supposed to have 80 psi and suddenly it’s got 120 psi in it, you’ve got the driver complaining about the vehicle’s rough handling, you’ve got tire wear issues. It’s extremely hard on the tire, and that’s dangerous.”
With nitrogen tire inflation, O’Brien is not seeing those extreme differences in tire pressure, so he can keep the tires closer to the manufacturer’s spec’s. As a result, tire failures, such as belt separations, have gone down.
To O’Brien, managing heat is all about moving air. If you can keep the air moving over and around the engine and drivetrain, constantly carrying that heat away, you might—might—keep your truck functioning in the desert heat of the Pahrump Valley.
“All that underhood heat, all that undercarriage heat, has to be moved,” O’Brien explains. “So, we’re looking at those tighter radiator assemblies and we’re pushing the air past the engine in large volumes and dispersing that air around the vehicle, not under the vehicle. And on a fire truck, it’s made worse by the fact that you’ve got the engine and transmission compacted together.
“You have to move that air past that engine,” he says. “If you don’t, you’re going to have EGR failures, turbo failures, you’re going to see the ceramics in those turbos disintegrate from the heat, you’re going to see poor performance and those engines aren’t going to be reliable.”
O’Brien is disappointed that he is only getting two years out of a radiator, and the press-on plastic tanks are melting. and starting to leak. To make matters worse, electric fan clutches are failing as well, so the cooling system can’t even keep up.
“We have looked at everything,” O’Brien says. “Cooling system capacities, extra coolant jugs, extra oil filters, extra oil coolers, looking at the grades of our oils and the oil change intervals. Most vehicles have oil changes of 3,000 to 5,000 miles at a maximum. We use parasynthetic oils; all of our rear ends are 100 percent synthetic, all of our hydraulic fluid and transmission fluids are 100 percent synthetic.
“We have found that by running synthetic fluids we get better life, we get better fuel mileage,” he says.
CREATIVE SPEC’ING & DESIGN
O’Brien seems to enjoy the challenge of spec’ing vehicles that can handle the unique demands presented by operating in the Pahrump Valley, even when that seems almost impossible.
Disappointed with his recent Ford diesels, for example, O’Brien has started to spec’ Dodge replacements. He is about to take delivery on a trio of new Dodge ambulances, but his efforts to spec’ a Dodge pickup to tow his hazmat trailer have hit a speed bump.
“It’s that thing every fleet manager goes through: what’s going to be the right vehicle for your fleet?” he asks. “What’s going to be the right option? You have to weigh the costs out.
“The last vehicle we got done spec’ing, we couldn’t buy it—it cost too much!” he says. “We just got done spec’ing a Dodge 3500 pickup truck, with four wheel drive, a trailer towing package, winch, full lighting package, and we blew our budget by $20,000. We’ll have to go back out to bid and take off some features. We’ll still order the vehicle, because we need it in the fleet, but I won’t get all the features I want. We may have to look at a lighter axle; I hope not, because I need that unit to tow the hazmat trailer.”
OUTSOURCING FROM 350 MILES AWAY
O’Brien used to maintain Pahrump’s fleet in-house, until an accident on an emergency call put him on the disabled list and he was forced to outsource.
Now, his vehicles are serviced at an assortment of dealerships and independent shops, many of them right in the neighborhood. Of course, in this case the neighborhood is Las Vegas, some 70 miles away. More specialized work can neccessitate a 350-mile drive to the American LaFrance service center in Los Angeles. Simple oil changes can be done in Pahrump, and the fleet’s new Dodge ambulances will be serviced at Pahrump’s Dodge dealer shop.
Since they come standard with all light-duty vehicles anyway, your fleet might as well start reaping the benefits.
Don’t get stuck out in the cold
Air-ride suspension maintenance, part II