The operation of such machines requires an understanding of the specifics of maintenance double-circuit heating system and features of weight distribution of bridges. The long wheelbase, although it improves stability on the highway, significantly reduces the turning radius, which is critical when maneuvering in the forest or on a construction site. The driver must take into account the shifted center of gravity and the inertia of the rear of the car, especially when driving on slippery soils or virgin snow, where the risk of the frame “grabbing” by the ground is higher than with short-wheelbase counterparts.
The choice between a factory double-row cab and a conversion with the installation of an additional module (KDM) depends on the requirements for safety and comfort. Factory versions Ural-43206 or Ural-5557 with an all-metal cabin provide better sound insulation and sealing, while modular solutions are often used to convert old military chassis. In any case, the key factor remains the condition YaMZ engine, which must have sufficient torque to pull the increased curb weight of the vehicle.
Design features and chassis designThe basis of any truck Ural with an extended cab is a reinforced spar frame. To accommodate a second row of seats or an additional section of the cab, the vehicle's base is lengthened, which requires the installation of an additional cross member and often a fourth spring in the rear suspension. This is necessary to maintain carrying capacity, since the weight of the cabin itself and passengers increases significantly. Spring suspension in such modifications it often has softer characteristics to increase crew comfort, but this requires regular checks of the stepladders and the condition of the spring leaves.
The cabin can be an all-metal three-door or two-door with an internal transition, or modular, installed on a platform. In all metal versions such as Ural Next or modern Ural-4320, the overall supporting structure is preserved, which has a positive effect on the rigidity of the body. Modular options, often found on equipment from earlier years of production, consist of two joined sections, where the joint is sealed with rubber seals that require periodic replacement to avoid moisture and drafts.
⚠️ Attention: When operating a machine with an extended frame, it is critical to regularly check the condition of the side members in the area of welds or joints, since this is where maximum bending stresses occur when driving over rough terrain.
System heating in such cabins it works under increased load. A standard one “stove” radiator is often not enough to heat the entire volume, so many modifications are equipped with additional heat exchangers or autonomous heaters. The length of the air ducts increases, which requires a more powerful fan and high-quality insulation of the pipes, otherwise the back row will freeze even with the engine running at full power.
Technical characteristics of popular modelsOn the special equipment market, the most common are several modifications that have proven themselves in different climatic zones. Remains the sales leader Ural-43206-1112-72, which combines a proven mechanical transfer case and a diesel engine YaMZ-65654 ecological class Euro-4. This model is often equipped with an all-steel, two-row cab that seats up to 7 people and has a 4x4 wheel arrangement, making it ideal for logging work.
A more severe option is Ural-5557-1112-72 with a 6x6 wheel arrangement. The presence of a third drive axle significantly increases cross-country ability, but increases fuel consumption and the complexity of transmission maintenance. Such machines are often used as chassis for installation crane installations, drilling or vacuum pumps, where a stable platform and the ability to transport a crew to the work site are required. The engine here is usually boosted to work with attachments.
To compare the main parameters of various modifications, it is convenient to use a summary table, which shows the key differences in dimensions and power plants.
| Model | Wheel formula | Engine | Power (hp) | Capacity (persons) |
| :--- | :---: | :--- | :---: | :---: |
| Ural-43206-1112-72 | 4x4 | YaMZ-65654 | 230 | 6-7 |
| Ural-5557-1112-72 | 6x6 | YaMZ-65654 | 230 | 6-7 |
| Ural-4320-1912-60 | 6x6 | YaMZ-236M2 | 180 | 6 |
| Ural Next 4320 | 6x6 | YaMZ-536 | 310 | 6 |
⚠️ Attention: When choosing a model, pay attention to the type of gearbox. Manual gearboxes YaMZ-1105 or 15-16 require switching skills, while modern versions can be equipped with automated systems that make control easier.
Advantages and disadvantages of double-row cabsThe main advantage of using Ural with a double cabin is the autonomy of the working group. A team of 6-7 people, along with tools and consumables, is delivered directly to the site, which eliminates the need to coordinate the movement schedules of several pieces of equipment. This is especially true for oil and gas fields, where laying temporary roads is not economically feasible, and the time of arrival to an accident is calculated in minutes.
Comfort in modern versions has increased significantly compared to its military predecessors. Installation air suspension seats, improved noise insulation and the presence of a berth (in some modifications) can reduce fatigue of drivers and passengers during long hauls. The all-metal body protects better from dust and moisture than tented superstructures, which is critical when working in swampy areas or winter taiga.
Features of winter operation
In winter, the extended cab requires pre-heating of the engine and interior. It is recommended to install Webasto systems or analogues, since standard heating may not be enough to quickly warm up the rear row in severe frosts below -30°C. It is also necessary to monitor the condition of the door seals, which harden in the cold and can allow cold air to pass through.
However, there are also objective disadvantages. The increased length of the base has a negative impact on geometric cross-country ability, in particular on the departure angle. When negotiating steep climbs or descents, the long rear overhang can scrape against the ground, damaging suspension components or fuel tanks. In addition, the turning radius Ural with an extended base it is much larger, which requires more space for maneuver, which is not always available in conditions of dense forest buildings or narrow quarry roads.
Maintenance and common faultsMaintenance of a truck with a double cab has its own nuances related to access to the units. The cab, especially an all-metal one, limits access to the engine and front frame elements. For routine maintenance, such as changing filters or checking the oil level, the cab often requires tilting, which takes longer than on short-wheelbase versions. Regular lubrication cardan shafts and the kingpins become even more important due to the increased loads on the transmission.
A typical problem for long-wheelbase modifications is fatigue failure of frame elements and cab fasteners. Vibrations transmitted from the wheels to the elongated body eventually loosen the bolted joints. It is necessary to periodically tighten the fasteners stepladder springs and check the status of the buffers. It is also worth paying attention to the exhaust system, which on such machines is longer and has more attachment points that are susceptible to vibration damage.
☑️ Weekly inspection checklist
The electrical circuit of the car is also more complicated due to the need to power additional consumers: a second heater fan, interior lamps, possible installation of a walkie-talkie or navigation. Wiring passing through the joint of frames or under the bottom must be reliably protected with corrugation and clamps to prevent chafing and short circuits, especially in conditions of high humidity and dirt.
Areas of application and specialized add-onsChassis versatility Ural allows you to install a wide range of add-ons on it. The most common option is rotational bus (PAS), which is an insulated body with seats, a heater and lighting. Such vehicles transport workers to remote drilling sites, logging sites and main pipeline construction sites. The passenger module can be made of sandwich panels or solid metal with insulation.
In addition to transporting people, these chassis are actively used for mounting special equipment. Loader cranes installed behind the cabin receive a stable base, and the presence of space for the operator and slinger inside the cabin solves the problem of their delivery. Also popular drilling rigs, where the cabin houses a control panel and a team of drillers, and emergency repair vehicles (ARM) with workshops and welding equipment.
Helpful advice: When ordering a chassis for a special superstructure, be sure to specify the total weight of the vehicle, taking into account the weight of the equipment and crew. It is often the case that the load capacity of a double cab chassis is less than that of a standard cab due to the increased dead weight.
In the oil and gas sector, versions with an increased protection class and air filtration systems are in demand, since the equipment operates in dusty conditions. For northern regions, the cabins are equipped with double glazing and enhanced insulation of the floor and walls. In the military sphere, such vehicles are used to transport crews of anti-aircraft systems or as command and staff vehicles, where the placement of radio equipment and officer workplaces is required.
Legal and safety requirementsThe operation of category C vehicles intended for the transport of people (more than 8 seats including a driver is already considered a bus, but up to 7 people in the cabin is a truck with a special design) requires compliance with strict rules. If the machine is used for the regular organized transport of workers, it may be subject to the requirements applicable to passenger transport, including the need to install tachograph and equipped with seat belts in all seats.
It is important to distinguish between factory versions and conversions. Installing a home-made module on a truck frame without appropriate certification and changes to the vehicle title is a violation and entails a fine, as well as problems when passing a technical inspection. Factory models Ural with a double cabin have all the necessary certificates of conformity and VTTS (vehicle type approval), which legalizes their use on public roads.
⚠️ Attention: Transporting people in the back of a truck (in a booth, on benches) without specially equipped seats, seat belts and permission is strictly prohibited by traffic rules and is life-threatening.
Drivers of these vehicles are subject to the same speed limits as trucks, but the presence of passengers requires a smoother driving style. Sudden braking and turning in a long-wheelbase vehicle with a high center of gravity can lead to loss of stability and injury to occupants. It is mandatory to have a first aid kit, a fire extinguisher and a warning triangle, and access to them must be ensured without unloading the entire crew.
FAQ: Frequently asked questions
Is it possible to convert a regular Ural into a double-cab version yourself?
Technically this is possible, but legally it is extremely difficult. You will need to go through the procedure for re-equipping the vehicle in an accredited laboratory, obtain a safety report, approve the changes with the State Traffic Safety Inspectorate and enter them into the PTS. It’s easier and cheaper to buy a factory chassis or a ready-made shift vehicle.
What is the fuel consumption of the Ural double cab?
Consumption depends on the engine model, load and driving conditions. For naturally aspirated diesel engines YaMZ-236 it is about 35-40 liters per 100 km. Modern turbocharged versions (Euro 4/5) can consume 30-35 liters, but when fully loaded and off-road, the consumption is always higher.
Do you need a category D license to drive a Ural with 7 seats?
No, if the vehicle registration certificate (PTS) indicates the vehicle as a cargo flatbed or chassis, category C license is sufficient. Category D is required only if the vehicle is registered as a bus (more than 8 passenger seats).
How are the back row of seats heated in winter?
Factory versions use a system of additional radiators and pipes coming from the engine. Efficiency depends on the serviceability of the pump and the absence of air pockets. In severe frosts, it is often necessary to install an autonomous hair dryer to quickly warm up the interior before driving.
What is the maximum speed of such a truck?
The design speed of most Ural models is limited to 85-90 km/h. However, due to the short main pairs in the bridges (for better maneuverability) and high windage, a comfortable cruising speed on the highway does not exceed 70-75 km/h. Excessive speed leads to a sharp increase in fuel consumption and tire wear.