Mack’s stronger LEDs
One of the brightest ideas to come out of 20th century technology is the light-emitting diode, commonly called the LED, which is replacing other forms of illumination in electronics, households, industries and motor vehicles.
In trucks, LEDs first appeared more than three decades ago as red tail and marker lamps and now are used in most positions on and in trucks and trailers. LEDs produce rich, vibrant red and amber hues at rear and side positions, while bright white color from headlights can better reveal the road ahead and any obstacles in and around it.
Mack Trucks adopted LED headlamps in its Granite and other models last year. They replaced the previously used halogens, which in turn were an advance over sealed beams that date back to the 1930s. LED headlamps are as much as 50% stronger than halogens, according to Mack. The LED headlamps are supplied by Grote, which coincidently was first to market with those red lamps around 1990.
LEDs are semiconductors that give off light when current flows through them. Development goes back to the early 1900s, and LEDs were first used in consumer electronics products in the 1960s. LEDs cost more to buy but are said to use one-tenth the energy and last 10 times longer than incandescent bulbs.
Another LED advantage is a cool operating temperature, which indicates low energy use. But that’s also a disadvantage in cold weather, because snow and ice can form over the light. So electric heating grids are built into the headlamp lenses to melt any frozen moisture.
LED headlamps are the main advance applied to a “refreshed” Granite, Mack’s principal vocational model used by operators of dump trucks and concrete mixers, among other types. Wondering if LEDs are as good as billed, I went to the builder’s headquarters in Greensboro, N.C., to see. My arrival was timed to include after-dark driving along country roads outside the city.
Tim Wrinkle, Mack’s vocational segment marketing manager and a mechanical engineer by trade, had a pair of Granite dumpers ready for testing. First I drove the latest model with LEDs, then the previous one with halogens. However, the results were somewhat inconclusive. I did see the whiter quality of LED light, which to my eyes is definitely preferable. But the halogens on the older Granite worked well too.
Yes, the halogens’ light was a bit more yellow, but the lamps otherwise did a good job of showing me the road. That didn’t surprise me, because way back in the early 1980s, I visited a tanker fleet in the Midwest that had begun using tractors with then-new halogens. They were so much better than the old incandescent sealed beams that the manager stopped spec’ing separate fog lamps.
There were two reasons the LEDs didn’t appear markedly better in my informal test with the Granites. There was still some post-sunset light in the sky, so the new truck’s headlamps couldn’t show off their brilliance. And they were aimed too low, reducing their effective range, while the older model’s halogens were aimed correctly. In outward reach, the LEDs’ high beams were equivalent to the halogens’ low beams. Had the LEDs in the newer Granite been aimed higher, I probably would’ve liked them a lot more. Incorrect headlamp adjustment is easily correctable, so that should be on a checklist when a new truck’s owner takes delivery.
The other feature of the refreshed Granite is revised styling in the front grille. It is now wider, and its chrome-trimmed bezel, or surround, has lost the V at its upper center and now runs straight across (the V and the two vertical side bars were supposed to form a big M, but that never visually registered with me). On the hood, air intake panels on each side are now slightly larger and rectangular instead of trapezoidal. Those mark the latest Mack Granite, so look for them when you see one coming at you, along with those modern LED headlamps – the better to see you with, dear trucker. LL