Many people associate KrAZ trucks mainly with mining dump trucks or 6×6 all-wheel drive army all-terrain vehicles.
However, not everyone knows about the little-known military KrAZ vehicles, developed at the Kremenchug Automobile Plant in the Special Design Bureau (SKB). These machines were ahead of their time, but, unfortunately, were never put into production.
The KrAZ-253B (6×6) was designed, as they say, from scratch. It had nothing in common with the all-wheel drive KrAZ-214 bonnet, which was then in production. First of all, the layout of the machine has radically changed. To make maximum use of the vehicle’s length to accommodate cargo, the cabin was installed above the engine. The Yaroslavl novelty – the YaMZ-238 diesel engine developed 240 hp. With. versus 205 hp With. the previous YaAZ-206B. The gearbox was experimental – 6-speed hydromechanical.
The wheel suspension was independent, torsion bar, on wishbones and with longitudinally located torsion rods. This made it possible to significantly lower the frame compared to the KrAZ-214 and thus lower the center of gravity of the vehicle. To save time, the cabin was borrowed ready-made from the civilian MAZ-500. The vehicle’s carrying capacity was 6 tons. This sample was designated as KrAZ-253B.
In 1964, more advanced models appeared – the KrAZ-E253 truck and the KrAZ-E259-E834 road train. The Yaroslavl engine has greatly increased its power. It was the latest, so far experimental, turbodiesel YaMZ-238N with a power of 310 hp. With. A more reliable gearbox was installed – a mechanical 8-speed YaMZ-238. The chassis load capacity has increased to 9 tons, and the maximum speed has increased to 71 km/h.
The cars received an original spacious cabin. Driving the car has become much easier thanks to power steering. An important innovation was a centralized system for regulating air pressure in tires, which significantly improved cross-country ability on soft soils and snow.
In 1968, even more advanced models appeared: KrAZ-2E253 and KrAZ-2E2592E834. They received a new cabin with simple, rational forms. The chassis load capacity increased to 10 tons, speed – up to 80 km/h. But the fate of the development had already been decided.
In the mid-70s, an idea matured in military circles of the USSR: to transfer some types of equipment of the Soviet Army from tracks to wheels. While maintaining the basic characteristics of the product as a whole, this reduced the cost of the chassis by 3-4 times. In light of this, the Kremenchug Automobile Plant was tasked with developing a family of military vehicles codenamed “Otkritie”.
In 1982, two experimental 8×8 vehicles were produced in the experimental workshop of the plant: KrAZ-ChR-3130 with two steered front drive axles and KrAZ-ChR-3120 with an articulated frame.
The KrAZ with an 8×8 wheel arrangement ChR-3120 and its extended version ChR-3120.02 had an articulated frame. The power and cargo sections were connected using a powerful vertical spaced hinge. The rotation of the front section of the frame relative to the rear was ensured by power hydraulic cylinders. The angle of rotation of the sections between each other was 40°. This provided the CR-3120 vehicle, which was 1.7 m longer than the KrAZ-3130, with a turning radius that was 0.5 m smaller.
The vehicle was equipped with a YaMZ-8421 multi-fuel diesel engine with a capacity of 360 hp. With. and a new ten-speed YaMZ-202 gearbox. The engine could run on both diesel fuel and gasoline, as well as rocket fuel with appropriate additives. The car received a front cabin from the KrAZ-260, but without a hood and tail, as well as an onboard platform 6.5 m long. It passed almost all preliminary tests.
In mid-1981, the USSR Ministry of Defense approved the tactical and technical specifications for the development of a new family of heavy multi-purpose vehicles for military needs. And soon a resolution was issued by the Central Committee of the CPSU and the Council of Ministers of the USSR, in which the Kremenchug Automobile Plant was ordered to begin creating this family.
And already at the end of the next year, 1982, KrAZ presented the customer with several variants of machines. The basic three-axle vehicle received the index 6315, and the four-axle one – 6316. In addition, the letter E (experimental) was added to the name of the prototypes. And in front of it was placed a number indicating the serial number of the development (for example, 3E, 4E, etc.).
All vehicles submitted for testing were equipped with the new YaMZ-8425 multi-fuel engine. It could work not only on diesel fuel, but also on gasoline and kerosene mixtures, as well as rocket fuel. Its power was 360 hp. s., and torque – 1400 Nm. Paired with it was a new dual-range 9-speed gearbox YaMZ-202. Such a power unit improved the traction and dynamic characteristics of the car by almost one and a half times.