KrAZ-260

KrAZ-260 at a glance: maker, years and purpose

The KrAZ-260 was designed as a heavy off-road truck for the army, but it soon found civilian work in quarries, oil and gas fields, construction and forestry. It continued KrAZ's line of three-axle bonneted trucks that began with the KrAZ-255, and its components later formed the basis of the KrAZ-6322. The plant's own story is told in the history of KrAZ.

History and development

Design work on a successor to the KrAZ-255B began in the KrAZ design bureau in the 1960s, led by chief designer V. V. Tabolin. The brief was durability and greater cross-country ability with a higher payload. The engineers kept the bonneted three-axle layout, but replaced the old wood-and-metal cab with a new all-metal three-seat cab, shared with the KrAZ-250 road truck. The first all-metal KrAZ cabs went into production in 1979, the year the KrAZ-260 began to leave the line, and series production of the standard truck began in 1981.

Compared with the KrAZ-255B, the cab was moved forward and the bonnet shortened. This lengthened the load platform and improved forward visibility. According to factory test data, the new truck was 11% faster, carried 20% more and used 6% less fuel, while its service life between major overhauls almost doubled.

What changed compared with the KrAZ-255B

The KrAZ-260 kept its predecessor's basic recipe of a bonneted cab, three driven axles and single wide tyres, but almost every major system was new or reworked. Moving the cab forward made room for a longer load platform, and according to the factory this alone added about 1.5 tonnes of payload. The turbocharged V8, the new two-speed transfer case with a lockable centre differential and the air brakes with spring parking chambers brought the truck up to the standards of the 1980s. Drivers also gained a lower, shorter bonnet, a better view of the road and a warmer cab, which mattered for crews working far from towns in winter.

Cab and body

The cab seats three and has heating and ventilation, a sprung, adjustable driver's seat and mounting points for seat belts, which made it comfortable by the standards of military trucks of its time. Removing the engine, however, requires lifting off the cab.

The standard body is a military-type steel platform with a drop-down tailgate, slatted side extensions, folding bench seats and frames for a canvas cover, so the truck can carry troops or cargo.

Engine, gearbox and drivetrain

The heavier truck needed more power than the KrAZ-255's engine offered, so KrAZ chose the YaMZ-238L, a turbocharged version of the YaMZ V8 diesel.

Because the truck works in dusty conditions, the engine has an automatic dust-extraction system and two-stage air filters. For cold starts it has a Thermostart flame-glow device and a pre-start heater. Sources differ on the gearbox: some describe the YaMZ-238B as a four-speed unit, others list eight forward and two reverse gears; all forward gears are synchronised. The front axle was adapted from the KrAZ-255B, while the middle axle is a new through-drive design. The driver locks the centre differential with a switch on the dashboard.

Suspension, brakes and steering

The front suspension uses a beam axle on two semi-elliptic leaf springs with shock absorbers, the spring ends sitting in rubber cushions. The rear bogie is a balanced suspension on two semi-elliptic springs with six reaction rods and sliding spring ends. Ground clearance is 370 mm, enough to clear deep ruts and rocks on unmade roads.

The service brakes are drums with a dual-circuit air system: one circuit for the front and middle axles, the other for the rear. The parking brake uses spring brake chambers and also works as the emergency brake, and an exhaust brake acts as a retarder. Steering is ball-and-nut with hydraulic power assistance, which makes the heavy truck manageable.

KrAZ-260 specifications

Older factory data list a slightly higher payload of 9,500 kg and a gross weight of 21,475 kg for some versions.

KrAZ-260 variants and modifications

The tractor unit could pull semi-trailers of up to 27.5 tonnes on paved roads and 23 tonnes on unpaved ones. The long 260G chassis carried pontoon-bridge equipment, bridgelayers such as the TMM-3M1 (from 1988), cranes, drilling rigs, water-purification stations, the ATs-10-260 fuel tanker and the EOV-4422 military excavator. In military service, the KrAZ-260 also carried missile and air-defence systems and towed radar and launcher trailers.

In service: strengths and weaknesses

Owners and operators value the KrAZ-260 for:

• Excellent cross-country ability, high clearance and deep wading.
• High payload and towing capacity.
• Tolerance of dust, heat and frost, and of overloading.
• Simple maintenance and good parts availability.
• Power steering, heating and an adjustable driver's seat.

Its weaknesses are high fuel consumption, limited visibility, cab noise, large dimensions and a cab that feels dated by modern standards. After 1993 the 260 gave way to the KrAZ-6322, and civilian buyers can still find used examples, often converted for quarry, forestry or crane work. Related models include the KrAZ-256 dump truck and the KrAZ-6510; all are listed in the KrAZ catalogue.