A short wheelbase. Hardly any rear overhang. A fully exposed chassis, sitting high, that oozes heavy-dutyness from front bumper to tail lights. That’s the typical profile of a classic 6×6 dump truck alright.
In the decades after the Second World War a 6×6 chassis was the norm in the earth moving business. Maximum horsepower output, comfort and speed were completely irrelevant in the (re)building era after the war. It was all about the payload capacity, durability and off-road capabilities. Crawling through our soft soil, with a dump bed loaded to the max, without getting stuck. That was its daily task.
Former US military 6×6 trucks, mostly GMC and REO, were converted into dump trucks on a large scale. German truckmakers also offered a line of high-quality on/off-road chassis. Logically domestic truck manufacturer DAF also wanted a slice of the cake.
In the fifties DAF had already built a 6×6 chassis, the unconventional -in all aspects- DAF YA 328 artillery tractor with its H-drive drivetrain. Their first civilian 6×6 chassis was the AZ 1900, introduced on the market in 1965.
This seems to be on a test “track”. Two guys in the cab and an engineer asking how things are working out. (Photo courtesy of DAF Trucks)
Apart from the 6-speed constant-mesh transmission and the transfer case, both manufactured by ZF from Germany, the full time 6×6 AZ 1900 truck was all-DAF. Its maximum legal on-road GVM was 22 metric ton (48,500 lbs). It has a fully welded chassis, hydraulic power steering and a mechanical air brake system.
From 1965 to 1970 the AZ 1900 was powered by DAF’s DS 575 turbo diesel engine. (Photo courtesy of DAF Trucks)
The DS 575 engine, a 5.75 liter inline-6, was DAF’s first turbocharged diesel engine, introduced in 1959. The maximum power output of the direct injected, 4-stroke power unit was 165 SAE-hp @ 2,400 rpm.
The so-called Frog DAFs with the standard dead front axle had their headlights mounted in the cab, see the red truck on the right. They moved to a lower position in the bumper on the AZ 1900 because of the height of the 6×6 chassis. The all wheel drive DAFs also got other and wider fenders, with a flat top side, so they could be used as a step.
The truck is equipped with a 3-way dump bed. Around 1970 the domestic competition for the AZ 1900 came from GINAF (Van Ginkel’s Automobiel Fabriek), Terberg and RAM (R.A. Mimiasie). Its foreign competitors were built by Magirus-Deutz, Hanomag-Henschel, MAN, Mercedes-Benz and Tatra.
Back then almost all 6×6 trucks were conventionals. Nowadays not one truckmaker offers a factory conventional model on the European market anymore.
There’s an AZ 1900 cab-chassis in the DAF Museum in Eindhoven too.
The production of this DAF model ended in 1973. In 1974 it was superseded by the FAZ 2200 DU 6×6 with the modern tilt cab. But times were changing, more power and payload capacity please ! After circa 1975 the 8×8 dump truck became more and more common in earth moving.
And in 1984 GINAF introduced this sensational 10×8 chassis with 3 steerable axles. As before, GINAF used DAF cabs and powertrain components for its magnificent specials. Euro-truck enthusiasts will recognize the DAF F241 cab from the 2800, 3300 and 3600 series. And just like on the DAF AZ 1900 the GINAF’s headlights also moved from the cab to the bumper.
Meanwhile our soft soil roaders with 5 axles have reached their peak, that’s the maximum legal on-road weight limit of 50 metric ton (110,000 lbs). As far as I know you won’t find them heavier, anywhere. Sure, in a quarry, but not on the highway or any other public road.
Here’s a YouTube video featuring the orange AZ 1900 I caught at the 2016 DAF Museum Days. Crawling up a hill, fully loaded.
DAF still produces a line of heavy-duty trucks for earth moving and other tough jobs, yet only as 6×4 and 8×4 chassis. No harm done, if you want all wheel drive, just call the Van Ginkel family. They’ll gladly use the DAF as their starting point.