Want to keep fuel costs down—and your bottom line growing—in 2015? Last month, our Cat Truck experts recommended two simple solutions: coast further in gear and slow down a bit. Read on for more common-sense suggestions in part two of our fuel-saving series.
Tip #3: Limit Idle Time
An engine at idle can burn half a gallon to a gallon of fuel per hour, depending on idle rpm and the number of accessories in use. (In other words, you’ll burn more fuel if the idle’s bumped up to 1000 rpm and the air conditioner, clearance lights and engine cooling fan are all running). That means the cost of leaving your truck idling while waiting in line to load or unload—or while sitting in a restaurant eating lunch—can really add up.
During the winter, when the ambient temperature is around 10 degrees with a wind chill below zero, it may make sense to leave your truck idling. But if the ambient temp is 30-40 degrees or higher, shut off your engine and save some money. A good rule of thumb: shut down the engine anytime you’ll be out of the truck more than five minutes.
Now, drivers often say they like the comfort of climbing into a warm cab when it’s cold out, or a cool cab when temperatures spike. But ask those same drivers how often they leave their own cars or trucks idling when they’re inside a restaurant eating dinner, and the answer is always no!
Another excuse you may hear is that diesel engines are hard to start, and that’s why it’s better to leave them running. That may have been true back in the days (1970s) of pre-combustion chamber engines, which featured glow plugs activated by a switch on the dash. In cold weather, drivers had to hold that switch—sometimes multiple times—to get the engine started and firing on all cylinders. Fortunately, those days are long gone. Today’s direct-injection, high-pressure fuel system engines are as easy to start as it gets.
Two additional opportunities to minimize idle time—and save fuel—are during warm-ups and cool-downs. At the start of the day, you only need to let the water temperature begin to rise off the bottom of the coolant temperature gauge. Even on cold winter days, that means you only need to let the engine idle long enough to do your pre-trip walkaround and fill out your log book. Once you start moving, take it easy for a few miles until the coolant temperature gets closer to normal. That way, you warm up the entire truck (axles, transmission, wheel bearings, etc.) instead of just the engine before you hit the road.
To shorten cool-down time, drive the truck as easy as you can just before you know you’re going to park it. Back out of the throttle early and let the truck coast as far as you can before stopping. The engine will be as cool as it can get as soon as you set the parking brakes.
Tip #4: Minimize Jackrabbit Starts
Are you guilty of jackrabbit starts? Breaking that habit could help you save fuel. Instead, use progressive shifting techniques when starting out and shifting up through the gears. (The idea of progressive shifting is to use only enough engine rpm to get up into the next gear and still pick up speed.) Go easy on the throttle instead of flooring it between every gear.
When starting off in the low side of the transmission, you can probably get by with upshifting at around 1200-1300 rpm, depending on the load and type of terrain. Heavier loads and uphill pulls may require more rpm to upshift. As your speed increases and you get into the high side of the transmission, you’ll need to use more rpm to upshift—the higher the road speed, the greater the rolling resistance. Try shifting at around 1400-1500 rpm.
If your truck has a Cat CX31 automatic transmission, use economy mode as often as you can. Go easy on the throttle as well, using only enough to pick up speed slowly. That’s right—you’ll be a few seconds slower getting up to speed. Will that delay really affect your production at the end of the day? That’s a decision you’ll have to make. One thing’s for sure, though—you’ll be pleasantly surprised by your end-of-year fuel savings.
Want more tips on saving fuel and money? Check out Caterpillar’s new Rethink the Tank website. It’s geared toward machine fuel savings—but there’s lot of relevant information for truck owners, too. Happy saving!