Advancements to the Doosan DL300 and DL350 wheel loaders provide operators with improved lift capabilities, increased fuel efficiency and enhanced cab comfort. This interim Tier 4-compliant machine (iT4) also has been engineered to deliver higher horsepower to tackle a wide variety of material handling applications — such as quarries, mines, road work and site development.
Designed with improved lifting performance, the DL300 and DL350 offer operators the ability to set upper and lower limits for both the lift arm and bucket stop positions from inside the cab. Better lifting capabilities improve cycle times in digging and loading applications, while providing better control of the lift arm and bucket positions. This feature allows the DL300 to effectively move material overhead with a dump height of 9 feet 4 inches, while the DL350 has a dump height of 10 feet — making it an industry leader in this wheel loader class.
To keep the wheel loader running at optimal performance in dirty and dusty conditions, the DL300 and DL350 incorporate a new automatic-reversing cooling fan that uses less power to cool and clean the machine. The operator can select to reverse the fan via a switch, or it can be set to automatically reverse on a preset time frame. Each time the fan reverses, it will run in reverse for a few minutes to clean the cooling system. This results in longer working hours and shorter maintenance time to clean the cooling system.
Operators can also expect upgraded driving performance options. As an alternative to the standard limited slip differential, the DL300 and DL350 offer an optional hydraulic locking front differential. Based on ground conditions, the operator can choose to lock the differential manually with a floor-mounted foot switch, or allow the machine to automatically engage the system. This provides increased driving power when one wheel spins or loses traction and improves machine performance when navigating tough terrain.
Another optional performance advancement for the DL300 and DL350 is a torque converter lockup clutch. This enables the machine to climb grades easier and faster, increasing productivity as much as 20 percent in certain stockpiling applications.
The 4.2-cubic-yard DL300 has been relaunched as a 271 horsepower iT4 wheel loader — up from 217 horsepower in its previous design. It is engineered with a breakout force of 37,993 pounds, a full-turn tipping capacity of 28,572 pounds and a dump height of 9 foot 4 inches.
The 4.8-cubic-yard DL350 has been re-engineered as a 271 horsepower iT4 wheel loader — up from 232 horsepower in its previous design. It provides operators with a breakout force of 37,768 pounds, a full-turn tipping capacity of 31,118 pounds and an industry-leading 10-foot dump height.
Both Doosan wheel loaders are equipped with 5-cylinder diesel engines that have been optimized for use with selective catalyst reduction (SCR) and diesel exhaust fluid (DEF) to comply with iT4 emission regulations. Engines with this configuration are optimized to reduce particulate matter (PM) by operating at higher combustion temperatures and to reduce nitrogen oxides (NOX) with exhaust after treatment using SCR technology. Additionally, SCR systems offer increased fuel efficiency - as much as 16 percent on this machine - due to the engine optimization, which improves fuel burn.
The 568-cubic-inch engine features a high-pressure common-rail (HPCR) design with direct fuel injection, electronic control and four valves per cylinder. The high-pressure common-rail system increases the efficiency of fuel delivery by increasing the pressure up to 34,000 psi. The increased pressure allows the injector to inject a finer mist into the engine, which results in a more efficient combustion that in turn produces more torque and improved fuel economy, less noise, lower operating costs and cleaner exhaust.
More new options for Doosan wheel loaders include a diesel-powered coolant heater to improve starting in cold weather or a block heater that warms the engine coolant before engine startup with an electrical heater.
Service intervals on the front lift arm pins have increased fivefold, from 50 to 250 hours, reducing operating costs and downtime. Tilt cylinder hydraulic hoses have been rerouted for improved hose reliability, better hose movement and improved visibility to the attachment.
With a focus on increasing cab comfort for operators, the DL300 and DL350 are now equipped with optional electric steering to decrease operator fatigue during repetitive cycle operations on the jobsite. A joystick has been added to the left armrest that allows the operator to control the directional movement without having to use the steering wheel. A new door makes getting in and out of Doosan wheel loaders — and cleaning the inside of the cab — much easier.
Interior cabin improvements also include a number of multi-function display panel upgrades on a centralized monitor that allows the operator to view comprehensive machine system information. The centralized monitor displays critical machine information - such as engine rpm, engine coolant temperature, fuel level, DEF level, machine warnings, time and the transmission selected gear. A key exterior cabin improvement is lowered front side glass, providing improved visibility of operations.
The DL300 and DL350 — like every new Doosan machine — are covered by an innovative 48 hour parts guarantee. The program guarantees that if a “machine-debilitating” part is needed, Doosan will deliver it directly to the end user within two business days or Doosan will pay for a replacement machine rental. The 48 Hour Parts Guarantee is subject to carrier delivery restrictions and/or governmental agency delays.