Mountaintop Classic: Mack L-Series Truck — Well-Baked

This one is not going anywhere. The isolated and difficult-to-reach location suggests that this one will stay put until it is a rusty spot on the bare ground—which will probably take a long time.


Hiking in the lesser-traveled mountains of the San Bernardino National Forest has yielded a find. This relic would have been an attractive truck in its day, for people who are into that sort of thing. As it is, we found it long-abandoned in a meadow topping a steep climb from the valley below. It must have been quite something to witness, watching and hearing this big diesel truck climb a fairly steep mountainside to its final resting place, many years ago.

Let’s answer three questions about this truck, shall we? What is it? How did it get here? And why is it triggering huge memories on my part?

The truck itself is an L-Series Mack, introduced in 1940 and built through 1956. There were multiple versions, but this one is likely a tandem-axle LF, of which some twelve and a half thousand were built. I recall the remnants of the straight-six engine still there, but I did not seek any identifying marks. Maybe next time. A large number were powered by Mack’s in-house END 672 Diesel engine, of 672 cubic inches and 165 horsepower, and that was likely the power source of this truck. The engine was called the “Mack Lanova”, licensing the German Lanova company’s combustion chamber design. This long-used series of Mack straight-six diesels, of various displacements, emitted a distinctive, extremely guttural sound. It was a widely employed Western U.S. truck, used for logging and other heavy loads to be pulled over hills and on rough roads. It was built for pulling power and durability, not speed or grace.

A Mack L-Series truck in better condition. In my mind, those wheels are distinctive and they trigger some memories.

The L-Series in its natural habitat, hauling logs in the Western U.S.

The “up the mountain” photos show a truck with not much left, but showing off the characteristic features of the bodywork. The rather droopy-edged split windshield recalling early days, along with free-standing headlights (trust me, that’s what they were), and a split hood with boxed sides and folding at the corners. The fenders were a complex affair at the front, being Partially faired into the central bodywork, but still exhibiting a look of free-standing front fenders. The pressed steel surround of the upright and fairly tall and narrow radiator was very pre-war. (Missing) chrome trim and the bulldog on the nose gave it a bit of old-fashioned style.

These trucks were old-fashioned, as they were introduced in 1940, and the basic styling was carried through to the end of the run in 1956. By then, even new examples would appear decidedly old-school, when parked in the vicinity of many other trucks, including one of the different Mack offerings.

Upright and squared-off, these trucks exhibited old-fashioned and immortal truck styling cues. The metal is of a very thick gauge on these beasts. Sitting on the ground without proper front tires and wheels, does not do justice to the size of the truck.

Mack experts could likely narrow down the production date through interpretation of the dashboard features. As it was, I didn’t want to lean in too far and possibly encounter rattlesnakes.

The L-Series was a medium capacity truck, and variations went up and down the ladder a bit on pulling and carrying specs. Suffice to say that, particularly in logging, they were likely often loaded well beyond their limits, and yet they still had a reputation for bringing home the freight, though not quickly. A reasonable maximum speed was likely 40 mph or thereabouts, and the brakes were no doubt of the “downshift and plan well ahead” variety.

Tandem axles out back. I would have liked to have checked those rear wheels for the rugged demountable wheel center castings. Maybe next time, if it is not snake season.

So, how might have this truck found its way up to a dry and scrubby So Cal version of a high mountain meadow, such as the Austrian Alps of “The hills are alive…” and Julie Andrews? The view from the area is fantastic, and I don’t find a rusty old truck taking away from the view. Most people’s mileage would likely vary considerably, concerning rusty hulks in pristine wilderness.

The view from the abandoned truck is spectacular, in the hot and dry Southern California idiom.

Much of the farming in the foothills of Southern California is owned or operated by a large agricultural empire. During and after World War 2, they added marginal, up-the-hill areas to their producing acreage, as war needs made extra demands. They grew (and grow) potatoes on a grand scale. The elevated mountain valleys offered reasonable growing conditions, and potatoes were planted in tucked-out-of-the-way places. The biggest impediment to doing all this was to deliver the potatoes down the hill, on narrow and sometimes steep roads, to San Jacinto, for further shipment. That’s where a truck like this one would come into play. It had the grit and the pulling power to get the crop, slowly and carefully, to market. As the outlying fields were taken out of production, this truck was likely driven up the mountainside, to a flat, out-of-the-way spot, and simply abandoned. Was the title out of order? Was the engine or driveline falling apart? Was the frame severely damaged? We’ll likely never know.

An artifact representing the possible operator of this truck. No one knows for sure.

The truck itself is located in the National Forest. It is accessed by an unmapped but Forest Service maintained hiking trail. The trailhead is extremely difficult to get to, hidden behind Native American tribal boundaries, and only locals know to access it. But everyone who locally hikes knows about the “truck”, which is located near some old pit mines, where rusty mining detritus is strewn about. The mines were worked in the early 20th century, while the truck was manufactured some decades later, so there is likely no connection there.

A series of whimsical signs were placed along the trail. The truck to the right, the mines to the left. I blocked out the name of the mountain on the sign. Let’s keep this artifact a secret, shall we? Since this photo was taken, most of the signs have been removed, either by thieves or by the Forest Service.

Finding this truck for the first time, the look and shape of it set off huge memory-bank bells for me. There was something about it that took me back to my early childhood. Looking up information on old Mack trucks, I made the personal connection. Back in my childhood, the local fire department used a Mack. It appears to be an L-Series, though the line of the rear of the front fenders is different and more streamlined. But firemen must enslave themselves to fashion more than lumberjacks, right?

Photos of the old Bonita fire truck are hard to find on-line, but a couple came up. The Bonita truck may or may not be an L-Series, and it was likely gasoline powered, not diesel, as I remember hearing the truck in parades (I was a kid who liked to listen to engines). But the old Mack truck vibe was definitely the same one.

The Bonita fire station, back in the day. The big Mack is on the left.

A more current photo. A bit hokey, but the best I can find. Note those wheel centers, in this case adorned with some chrome “dog dish” style caps. Bonita’s firemen rolled in style.

Links and connections, and a rusty hulk evoking some fine old trucks. Call up some YouTubes to hear these things under power. There is actually remarkably little on-line about these trucks, to my surprise.

A fine example of an L-Series fire truck. This one is from New York State. Not all of them ended up in the West. Like most L-Series fire trucks, this one has a gasoline engine.

One more L-Series, appearing original, aged, and unrestored. Because more photos are better than fewer photos.