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IMP Automobilbau - Heavy Bois


Tales from the IMP Conservatory: 1945-1955

The IMP 2400 was a large saloon car equipped with a 2.4L straight six engine of pre-war origins, it was the first non-commercial passenger car sold by IMP after the war. The design itself had been finalized in 1939 and was supposed to be an entry level model for the then relatively new car division. Due to the war and the susbsequent rebuilding effort it would take another ten years until the car finally reached production.

  • 2.4L Inline 6
  • 75-100hp
  • 1949-1956
  • 3,400 units sold (approx)


The 1952 L6 was the first new passenger car developed after WWII. Built around a robust monocoque with independent front suspension and a coil sprung live rear axle with a panhard rod and anti roll bars only a four door saloon bodystyle was available. The two ton behemoth was powered by IMPs new overhead camshaft 3.8L Inline six engine initially with 155hp, making it the most powerful german production car at the time of its introduction and capable of 180kph. Later models featured more power and an optional two-speed GM automatic transmission.

  • 3.8L Inline 6
  • 155-200hp
  • 1952-1960
  • 1872 units sold


The IMP 1500 (also referred to as the F53) was launched in 1954. Mechanically and stylistically it was a scaled down L6, and powered by a new cross-flow four cylinder engine with an aluminium alloy cylinder head. A floor mounted 4-speed manual transmission was standard. An 1800cc engine and a 2000cc inline six were made available in 1955. The F53 was the first mass-produced car by IMP.

  • 1.5L I4, 1.8L I4, 2.0L I6
  • 65-90hp
  • 1954-1960
  • ~14600 units sold

The IMP S180 was a sports version of the F53, only available as a two-door sedan. It was based on the 2.0L Inline 6 engine, but triple carburettors and classic tuning increased engine power to 115hp. The name was chosen du to its 180kph top speed. Wire wheels and dual headlights distinguished the S180 from its tamer counterparts.

  • 2.0L Inline 6
  • 115hp
  • 1957-1960
  • 755 units sold


The IMP GT was a four seater sports car sold by IMP between 1961 and 1977 in two generations. The first model was supposed to be launched in 1959 but was delayed due to high demand for the small Teuton sedan. The GT is the last IMP vehicle to bear the 1950s design language with baroque shapes and lack of the distinctive elliptic headlights. Mechanically it was up to the highest standards of its time, with a three-link live rear axle and an aluminium alloy OHV straight six with hemispherical combustion chambers, which produced 105hp in standard form and 130hp in triple-carb form. In 1964 the 2.0L engine was enlargened to 2.7L and produced 165hp. 1966 saw the most major change to the new DOHC 3.6L V8 with 225hp and standard five-speed manual transmission, accompanied by a modernized exterior and interior. The GT S-V8 was a very fast machine, but also a lot more comfort oriented than its six-cylinder predecessors which resulted in a drastic weight increase from 1270 to 1410kg. In 1968 the GT S-V8 was replaced by a radically different and futuristic successor. The Straight sixes are more desirable to purists, while the effortless V8 has the broadest appeal and can be found most easily especially from the US.

  • 2.0L or 2.7L Inline 6 OHV, 3.6L DOHC V8 Fuel Injected
  • 105-225hp
  • 1961-1968
  • 2448 units sold


The only luxury (F segment) estate, if I’m not mistaken. Interesting idea.


Sort of like a Lister Storm. 1.6 ton tank of a car. 1997 Model year. Huge great big naturally aspirated 7.0L V8, 750hp in race trim, 650 road legal. There were 15 of those. Seen here in IMR Motorsport White and Purple livery, without sponsors.


im not one for old cars, (2009 and below) but, that looks good!


This is NOT an IMP, although it got very close.

This is number 29 of 44 1987 Hermes Supercontinental Prototypes. You know, the failed 1980s Supercar made from granite.

Since the Company went bankrupt just before the car could be put into series production, these 44 Pre-production cars made their way into private hands since all of them had VIN numbers and type approval and were thus completely free to be registered and driven. Many were swapped to cheap and easy to maintain mass-produced V8 engines from a variety of american makes, some were converted into race spec, one was converted into a rallye car, and about 10 kept their original V8 engines including No.37 which had since been stroked to 7.0L and twin turbocharged. A few were even painted in colours other than nicotine beige.

And then there was No.29, the most radically tuned of them all. This example found itself in the posession of Pneumatech Automotive Systems AG, a german based engineering company specializing in tyre technology and pneumatic systems for Cars, Trucks and Industrial equipment.
Pneumatech would go on to completely rework the entire body, chassis, drivetrain and suspension as a test bed mainly for real world high speed tyre testing. Initially the only modification was the fitting of a new type of electronically controlled self levelling air suspension system, which would (in upsized form) later find its way into several high-end trucks. Eventually after hundreds of thousands of km the worn out engine needed to be replaced with something newer, more powerful, and reliable.
Since Pneumatech was an important supplier of IMP, this relationship was crucial in securing a development mule of the yet to be released IMP VR60 V8 in 1994. This Quadcam brute of an engine produced 100hp more than the outdated 6.4L while being nearly 100kg lighter as well. With 450hp the vehicle was now capable of exceeding 200mph even with the ancient 3-speed automatic still installed, and the car became a valuable asset in testing high-performance tires. But the car began to show its age, after over 400,000km with a largely original frame. As a final sendoff, in 1996 the Supercontinental was yet again sent back to IMP, or rather the IMR specialty cars division.
There, the car was completely stripped of all its parts, which were then each refurbished and updated to modern specifications. The chassis was fitted with carbon fiber reinforcement beams, the rear driveline subframe was removed and instead the engine became a stressed chassis member with prototype Pneumatech active engine mounts for isolation. The air suspension was once again uprated to include active roll stabilization, the car was put on fresh high performance tyres in 255/45R18 up front and 325/35 R18 at the rear, and the body panels were restyled in a wind tunnel to give a more modern appearance and improved aerodynamics. Also the Interior was redesigned to look more modern.
But the party piece was the engine, the 6.0L V8 had been bored and stroked to 7.5L, fitted with higher lift camshafts and individually balanced rotating assembly. Oddly enough, the compression was actually lowered to 10,5:1 instead of the original 11,5:1, which enabled the use of cheaper 95 RON fuel. Also new was the gearbox, a modern 5-speed automatic unit lifted straight from the IMP Opera. The result, called the VR75X1, produced 610hp and 760Nm of torque.

The old yuppie’s dream could finally live up to the expectations it failed to meet in the late 1980s, with a top speed of over 220mph, massively improved comfort and stability, even improved fuel economy. It is rumoured that when the car was presented at the major 1997 Auto shows, Pneumatech and IMP received several blank checks for a ten year old car made by a company that closed its doors in 1989.

Even so, in 2000, the car was once again sold off to a private person for the reasonable sum of DM350,000, a great value considering the millions of development money that went into it during the decade prior, and the lifetime warranty with full coverage granted by IMR due to its unique prototype status.

If you ever wanted a Supercar from IMP, a 1987 Hermes Supercontinental with over 650,000km and almost no original parts might just be the only chance you’ll ever get.

Automation x BeamNG Car Repository

Back to form, with an old-school touring car.

This particular IMP 2000 Saloon was modified by IMP-Monolith of Great Britain Ltd. to compete in British Touring car races. Of note was its purple and silver paint, the first known appearance of the classic IMP racing colours, later replacing the silver with white to mirror the corporate colours. It was modified by stripping unneccessary weight and installing a new engine, still based on the original C-2000 Straight Six architecture but modified with triple SU Side draft carburetors, very aggressive cam profiles and an unmuffled exhaust. In that configuration it was said to have produced over 150hp, which was quite a lot considering its relatively small size and weight. Only the Jaguar Mk.IIs (equivalent Bonham?) and some of the american contenders could outaccelerate the 2000, but couldn’t match the smaller IMP under brakes and cornering. Over the course of four years the IMP could accumulate an impressive ten race wins on the UK circuit, and was among the fastest cars on the track when not impeded by accidents or mechanical failures. Also impressive was the fact that during the entire campain only one car was used, which survives to this day.
It’s recently been restored to its original purple and silver livery, and the fast but finicky 2000cc engine had been replaced by a 2300cc Monolith based engine, stroked to 2500cc, and fitted with an improved cylinder head from a mid-1960s IMP GT. The brakes were upgraded to Findling four wheel discs.


A rebuild of a fairly well known car.


The origin story of the 1995 Impakt has become something of a legend, due to it supposedly being developed out of a purpose built Class 1 DTM touring car, with its race car like double wishbone suspension and transaxle drivetrain layout. The reality is somewhat more grounded, the race car and road car were developed simultaneously, with the racing model debuting in late 1994, over a year before the road going model. But the street legal version was not a tamed race car. As a matter of fact double wishbone suspension and transaxles have been used by the larger IMP sedans since the 1960s, and this familiarity and the inherent dynamic advantages finally made their way into the small one as well. The one thing the normal cars actually inherited from the touring car were a very quick steering rack and complex dampers that allowed even better control at the very limit, but they made the car more nervous in regular driving and were very expensive to manufacture and thus both scrapped with the 1999 revision. The engines were largely inherited from the predecessor, a 1.7L Inline 4 marked the cheapest model, while a variety of larger four, five and six cylinder engines based on the same architecture expanded the range from just 106hp to over 210hp. Of far more importance were the new diesel engines, not only sporting four valves per cylinder but also multi-stage direct injection, ranging from a 90hp to a 110hp 2.0L, both turbocharged and intercooled. These were derived from the 140hp 2.3 that had debuted in the larger Magnum two years earlier and made the Magnum one of europe’s leading taxicabs and fleet models.

Of course when talking about the Impakt one is by law required to mention the 260R, the one with the most similarities to the racing version, namely the loosely related 2.6L V6 engine, the wide low-profile sports tires with 17" magnesium wheels and sports tuned suspension. The R was the only model of the range to retain the motorsport inspired dampers and faster steering after the 1999 facelift. Peculiarly the 260R also attracted a special kind of driver to normal Impakt versions, namely wannabe race car drivers on a budget, since the Impakt had fairly high dynamic limits even in base form, it was incredibly common to see them being driven far beyond the safe speed limits, making the Impakt at one point the most ticketed car in europe, which in turn resulted in skyrocketing insurance premiums. This caused a considerable slump in sales after a few years, not helped by the competition introducing new and fierce competitors (looking at you, Erin Tauga, obviously). Nevertheless the Impakt remained IMPs second best selling range for the entirety of its ten-year production run, and why wouldn’t it? It was after all an economical, versatile and very reliable compact saloon with actual street cred.


Continuing my series of lazy rehashes of old Kee cars with the biggest and best of them all. L6, which stands for “Luxury 6 Cylinders”, which is why the third generation was only ever sold with V8 engines. But boy, what a V8 that was.

The L6 had always been exceedingly large and excessive for a european luxury vehicle, but this americanness gave it a certain charme, which was bolstered by cold, hard, german engineering. The third generation would take this all one step further.
The V8 engine was and is the gold standard for luxury cars, so IMP needed their own, even though some in fhe engineering department preferred an Inline 8 for a variety of reasons. In fact those people had just finished work on a 280hp 12L Inline 8 diesel for IMPs heavy truck division. But an Inline 8 was deemed impractical for a regular limousine, especially when the design brief called for near 50/50 weight distribution and a low center of gravity. So a V8 got the go-ahead in 1963.

Naturally only the best would do, the engine turned out to be a technological marvel for the time, all alloy construction, two valve DOHC cylinder heads and a roller bearing crankshaft with five main bearings. Initially carburettors were considered, but quickly abandoned in favour of mechanical direct (!) fuel injection. Which was prototyped but eventually redesigned into indirect injection due to less smooth engine running characteristics. The resulting 3.6L engine produced 225hp and 324Nm.
Remarkably the engine development was finished and production was up and running after less than three years, but the car wasn’t finished yet. So, to test out the early batches of engines and iron out the last few kinks the engines were installed in late second gen L6 and the new F65 executive sedans. Also, a simpler 4.1L variant for medium duty Monolith trucks was designed as well, this one indeed with a single carburettor.

The Gen III L6 was finally finished in late 1967. A highly modern car, with american inspired Coke Bottle styling, but a true tour de force of tech underneath. Conventional rear wheel drive, unequal length wishbone suspension on all corners with progressive rate coil springs and gas shock absorbers, four wheel disk brakes, a safety cell with padded dashboard and steering wheel, three point seatbelts for every passenger, true crumple zones, strengthening beams in the doors and an integrated roll cage meant the car was indeed as safe as it was heavy, even though use of aluminium in non structural parts kept weight reasonable.
Comfort was assured through a selection of fine interior materials, a standard multi speaker stereo radio and two-zone air conditioning and power everything,

1968 saw the introduction of a more powerful 4.7L engine with 282hp. This engine was accompanied by self leveling hydropneumatic suspension with a system counteracting body roll and pitch. The only visual differences were larger 16" wheels and quad exhausts as opposed to twin exhausts.
Both engines came coupled to a 3-speed Jager Turbomatic 500 transmission with a lock up converter, but the smaller engine could be special ordered with a 5-speed manual at no additional cost.

1973 saw the only major change in the production run, as both engines were modified to run on unleaded gasoline (for the american market) and accordingly received a displacement boost to 4.0 and 5.0L respectively (for the american market). In one market though, the 5.0L engine did not get the power robbing unleaded treatment, but a freer flowing exhaust system instead. German market 5.0 Super did thus produce 60hp more than all others and were capable of 250kph (155mph) flat out.

With the oil crisis of 1973 sales of the L6 tanked hard, not that they sold in boat loads to begin with. The L6 was unceremoniously discontinued in 1976, but it left a lasting impression. Not just because of its specs, but because of how reliably the car as a whole worked even in the face of abuse and neglect. In that regard the L6 was the ultimate IMP.

1967 to 1976 IMP L6:
3.6L or 4.0L DOHC V8 16V [IMP G3600E/ G40E-U], 217-225hp, 324Nm (both), 3AT (5MT optional), ~225kph (140mph)

1968 to 1976 IMP L6 Super:
4.7L or 5.0L DOHC V8 16V [IMP G4700E/ G50E-U], 275-282hp, 405-430Nm, 3AT, ~235kph (145mph)

1973-1976 IMP L6 Super (German market only):
5.0L DOHC V8 16V [IMP G50S-E], 336hp, 468Nm, 3AT, 250kph (155mph)


You’ve seen it before, you’ll see it again. 1977 IMP Opera (Gen 1)

You know what it is, another large sedan from IMP, the quasi successor to the L6, albeit considerably smaller and less filled with tech. It is sitting not on the L6 platform (which first appeared in 1952) but on an enlargened version of the F65 platform. However the Opera platform greatly differs from the F65 in several ways. For one, the engine and transmission are mounted in a conventional north-south arrangement and form a unit with the transmission. The F65 had its transmission mounted at the rear differential. Due to this the front axle has to bear higher loads and is virtually identical to that found on the far larger and heavier L6. The rear axle meanwhile may be considered a downgrade as it is no longer of double wishbone design but a simpler semi-trailing arm arrangement. This is in essence one of the earliest examples of cost cutting on an IMP. As a result the Opera was slightly more difficult to drive than the L6 and F65 in adverse conditions, which in a practical scenario was complete moot. The Axles however were significantly stronger than the two predecessors, which made armor plating more common on these. The Car in general was very durable, a galvanized chassis with simple but effective high quality steel body panels and the reinforcing elements of the L6.

Engines! My favourite thing to talk about. They were carryovers from the L6. At least the 215hp (less with USDM Catalytic converters) 4.0L V8 was. The 5.0L was discontinued and a 4.6L took its place. The 4.6 is actually based on the taller 4.5L Monolith block and shares its conventional crankshaft assembly. By changing connecting rod lengths the stroke was however identical to the 5.0L which resulted in the aforementioned 4.6L displacement. Cylinder heads were shared with the 4.0 and brough the figures to 260hp and 370Nm (less with USDM Catalytic converters). Both engines used IMPs first self developed automatic transmission, with 4-forward speeds and a hydraulically actuated clutch instead of a torque converter.
In 1979 an entry level 3.0L Straight six was added, with 175hp (less with USDM Catalytic converters) and a 5-speed manual transmission.
There were only minor changes to the range in the following years, 1982 saw yet another different engine, a 3.4L 24V Straight 6 and electronic fuel injection which had a catalytic converter as standard and made 180hp, but was a significant improvement over the older 3.0 in terms of fuel economy (as much as 3L per 100km less).

But you all know what is coming next. Time for the Diesel.
1984 was the most important year for the Opera, as it introduced the world to two of IMPs most popular engines of all time, the H-series 3.8L straight six and the D640 4.0L Turbodiesel. The H-138 was in essence a stroked version of the earlier 3.4L, but thanks to several detail improvements the 3.8 boasted with 240hp and 350Nm, some very impressive numbers for the early 1980s inspite of a power robbing cat. This engine replaced the 4.0 V8 and was once again available with a manual transmission. Yet the real star was the Diesel. The new 4.0L I6 was a clean sheet development and at first glance fairly unremarkable, a single overhead camshaft that operated on 2 valves per cylinder, and by the numbers pre-chamber injection system fueled by an R-ESP Inline pump. But that was what made the engine great. Simplicity also means ease of maintenance, and first and foremost reliability. The engine block was unique to the 640, engineered to be especially strong and overbuilt in a way only 1980s germans could. Fully forged rotating assembly. Carefully designed oiling system with a dry sump that ensured full lubrication of critical parts on startup without adhering to warm-up phases and immunity to extreme driving situations. Maintenance free shaft-driven valvetrain. “Runaway Valve” that completely blocks the intake air flow in case of a runaway, preserving the engine.
It was a truck engine in a car, simple as that. However the 640 was indeed very smooth as well as a lot of attention was paid to smoothing out the combustion process. Power was provided by a Turbocharger and Intercooling. 165hp and 395Nm were some serious numbers for a diesel in the early 1980s and made the Opera Diesel reach a Top speed of 190kph.
However all this came at the expense of fuel economy. Even at launch the engine was considered to be only averagely efficient, being only marginally more frugal than the 3.4L petrol (10.5L/100km vs 12.1L/100km). But the engine did prove a popular choice especially in North America as it was one of very few engines available at the time that had V8 power with six cylinder economy and turned out to be especially unkillable and tunable, able to withstand over 700hp on a stock block and 1000+ when built up. The Diesel and 3.8 quickly became the most popular engine choices, despite their short three year production run these two made up nearly two thirds of all Opera sales.

Amongst all this Diesel fappening one must not leave out the new for 1984 270hp 4.9L V8 with EFI and Cat and the facelift that was necessitated by the especially large 4.0L Diesel, that resulted in an elongated front end for all models.

So, to sum up: The original Opera was perhaps a step-down for some purists in terms of “money no object” technology, yet it was part of the commercial turnaround for the car division, which by 1975 was eclipsed by the heavy trucks division in terms of sales. And it enhanced IMPs reputation for conservative yet extremely durable engineering.

IMP - Absolute dependability.


Just a fun little side project - oddly enough I have never built a Taxi on UE4. Nothing special, just a washed out 1965 IMP 2300 Diesel that has chauffeured thousands upon thousands of people to destinations in and around Cologne, Germany. Somewhere around 1.7 million miles and two engines were conquered in some 50 odd years of service. Recently been mildly restored with the original black paint scheme applied and a rebuilt drivetrain. I call it the Iron Mule.


if the roof was green , i was seeing the taxis of my childhood




Lore friendly replica of my personal 1995 Nissan Maxima SE. Lore friendly replica is a loose term, since this is only what my lore equivalent would look like and has absolutely nothing in common with the real thing other than the vague specification and colour. In my case the base engine, 5-speed manual transmission, velours seats, 6-speaker Cassette Stereo, electric sunroof, fog lights and 195/65 R15 alloy wheels.

Other than that the 1993-2001 IMP Magnum is a wholly different animal. Starting with the chassis, IMP only really does RWD, so the engine is longitudinally mounted. Speaking of the engine, whereas my Nissan was powered by a 2.0L V6 with 140hp, the lore equivalent is powered by a 2.2L 16V Inline 4 with balance shafts and 140hp, but 207Nm of Torque compared to 177Nm. The front suspension consist of a sophisticated A-Arm setup on all four corners as opposed to the cost saving Strut/Beam combo. Brakes! Almost Identical, 280mm Vented with two-piston calipers up front and 275mm solids with a single piston at the rear. And most importantly IMP has used high quality steel with considerably better rust protection. The end result is 60kg heavier, slightly faster to 100kph in 9.6s, has a considerably better top speed (216 vs 201kph) thanks to better top end performance of the engine, gets noticeably worse mileage (11L/100km vs 9,9L/100km) and also has more fade resistant brakes.

And it looks like this.


Of course it was and is a common practice for manufacturers to sell production licenses to countries that have a lesser developed automotive industry, the idea being that it makes more sense to adopt a proven and reliable design from an experienced manufacturer to avoid having to waste resources developing a vehicle from scratch.

IMP was also involved in this. The first foreign made (i.e outside germany) IMPs were built in Finland in 1941, a direct result of the War effort. Finland, after declaring neutrality and then fighting the Soviet Union in the Winter War of 1939/40, had just allied itself with the Axis in order to reclaim lost territory. IMP was quick to capitalize on that by supplying the finns with light and heavy trucks to support their forces. Thus the Raskas-IMP Autotehdas Ab was established to assemble certain models from CKD Kits. Even before the war, imported IMP Trucks (remember, no true passenger car production to speak of yet) were fairly popular in Scandinavia due to their ruggedness, maintenance friendly construction and capability. It is estimated that around 50.000 Trucks were built from 1941 to 1945. After the War, production of these military trucks continued independently, now relying on a greater quantity of locally sourced parts due to the heavily damaged german factories. Later the relations were reestablished and new, civilian models were introduced.
By 1957, car production became more prominent resulting in Raskas-IMP producing their own IMP F-Series Saloon cars, modified to better suit the environment by adding larger wheels and raising ride height. These cars proved fairly popular as taxis and law enforcement vehicles.

As time continued the cars differed more and more from their german made cousins with different interiors and modified running gear. By 1968 the then current IMP F65 was transformed into the much different Raskas 400 Series. The 418E and 419E may shared the bodyshell with the F65 sedan, but they used the tougher live axle suspension and drivetrains from the earlier F60. The 419 was an especially ambitious project, with an Aluminium DOHC Cylinder Head and Twin Carburetors on the Raskas RBT20 engine (in fact a modified IMP D20a) giving 115hp and making the car very prestigious.

The Raskas 400 series was also exported to the less capitalist Red states, again making a formidable taxi and law enforcement vehicle, because no common laborer could hope to acquire one. The 419N as the communist special was referred to retained the RBT20 Twin Cam engine but modified to accept commonly available low-grade fuel with only a mere 105hp but remained in production all the way until 1988, way after the regular 400 series was phased out in favor of more modern cars.

Top image: 1969 Raskas 418, identifiable by its lack of a bonnet bulge and single headlamps


This is a 1977 IMP 15.38 SL 6x4 Tractor, Series HS76. It is towing a 27 ton iron ore trailer. This model was used in an off-highway setting to transport the valuable raw material to a nearby railway for further transport. As such the cab is very spartan, a low-entry day cab. Of course the 15.38 was far more versatile than that, but it was most popular for such heavy duty applications thanks to the mighty 15L V10 Turbodiesel powerplant.

Specs: 1976-1982 IMP HS76 15.38

Engine: [IMP DT410.385]
90° V10 OHV Turbodiesel, cast iron block
Bore x Stroke: 124x124mm
Displacement: 14.974cm³
Individual cast iron cylinder Heads, four valves per cylinder
Mechanical direct injection, in-line fuel pump.
Single Turbocharger with a 67mm Turbine, 88mm Compressor
Engine Weight (dry): 1046kg
Power Rating: 387hp @ 2150rpm, 1760Nm @ 1100-1700rpm

Chassis: [IMP Type 76L6]
Ladder frame, 3 axles with leaf springs
6x4 configuration, twin rear drive axles

Transmission: 5, 8, 12, 12+1 or 16+1 gears,
Final drive ratio: 2.78, 3.03, 3.38, 3.96 or 4.78
GVWR (tractor): 22.000kg within EEC regulations
GVWR (tractor-trailer unit) 38.000kg within EEC regulations

Top speed: 65-140kph depending on transmission and final drive ratio
Fuel economy: 32-60L/100km depending on load and drivetrain


jusging by the name i would say that your company is german.
and for germany, yout tractor-trailer unit is overweight by 22.000kg

semis are only allowed to weigh 40.000kg in total

plus the amount of axles would classify it as a special transport, which would negate the weight issue, but you would have to announce every distance driven by it on the open road to the town/ region it is driving in


I am well aware that trucks have to adhere to regulations, but nowhere did I specify in which country the particular truck in the image was being used. As a matter of fact I explicitly stated that this truck was used in a strictly off-highway setting, meaning the StVZO doesn’t even apply here (actually the legal weight limits in the EEC in 1977 were 22t for a three axle tractor and 38t for the tractor-trailer unit).
The truck is being used by a mining company on their private property to ferry the ore out of the quarry to a nearby railway where the material is transferred onto a train for further transport. Since Germany is a rather minor player in terms of ore production, it is unlikely that the truck was even built there (impromptu lore expansion: IMP also assembles trucks outside of Germany).
It is most likely a central or south american model, due to LHD.