This Duramax cooling package was built around a problem you don’t see in a normal truck: huge heat load, very little vehicle-speed airflow, and both engine coolant and charge-air cooling to manage at the same time. The fix is two separate radiator systems—one for engine cooling and one for the intercooler and aftercooler side—backed by electric fans, dedicated pumps, flow meters, and temperature sensors at the inlets and outlets. That matters because cooling performance is more than radiator size. We want to know coolant flow, temperature gain across the engine, and temperature drop across each cooler so we can see whether the system needs more radiator, more pump, or both. With Banks iDash Pro and our analog sensor module, all of that data can be monitored and logged in one place. On a supercharged twin-turbo Duramax, that’s how you build a cooling system that can be validated under load instead of guessed at in the shop.
The video introduces a custom cooling package developed for a monster truck. The system centers on a large engine-cooling radiator fitted with dual 16-inch Spal fans, along with a second radiator dedicated to charge-air cooling. Although the segment begins as an unboxing, the parts had already gone through design, fabrication, and installation mockup work before returning for final testing and assembly.
The radiator itself was built in Glendale, Arizona, then shipped through multiple locations before arriving back for inspection, which explains the worn shipping box. Once unpacked, the components are presented as finished hardware intended for installation in the chassis after dyno-cell validation.
The cooling system was not designed in isolation. The team already had the monster truck chassis modeled in CAD, and Joshua used that digital model to place both the engine-cooling radiator and the intercooling radiator. From there, the plumbing layout was developed, including hose routing, pump mounting, and the locations for all required fittings such as inlet and outlet ports, water-temperature bungs, drain bungs, and fill bungs.
Those drawings were then sent to Sparks Motors in Utah for fabrication and installation work. Rush Kane at Sparks Motors handled the fitment and welding, and the finished assemblies were boxed back up and shipped out. What appears in the video is therefore not a rough prototype, but a completed set of cooling components that have already been integrated into the chassis layout and are now ready for testing.
The cooling approach is driven by the operating environment of a monster truck. Unlike a conventional road vehicle, cooling airflow is not primarily created by vehicle speed. Instead, the radiator fans must provide the airflow directly. In that sense, the system is described as being closer to what might be used on a Baja trophy truck, where cooling performance must remain effective under low-speed, high-load conditions.
This application is even more demanding because the truck uses a supercharged, twin-turbo diesel V8. That combination creates substantial thermal load not only in the engine coolant circuit but also in the charge-air system. For that reason, the truck uses two separate radiator systems rather than relying on a single cooling loop.
The first of the two systems is the engine-cooling loop, built around a Duramax engine. That engine uses an internal, gear-driven water pump, which offers an important packaging advantage: the engine can be run without a fan belt. In this build there is no fan belt, because the cooling fans are mounted directly to the radiator rather than being mechanically driven from the engine.
Temperature will be measured both entering and leaving the radiator. In addition, the team pays close attention to temperature change across the engine itself, defined as the gain from water-pump inlet to thermostat outlet. Gale explains that his preferred range is an 8 to 12 degree temperature gain across the engine. If the system operates outside that range, especially above 12 degrees, it suggests the need for either more radiator capacity or more water-pump capability. A coolant flow meter will also be installed on the cold side of this circuit so that temperature behavior can be evaluated alongside actual coolant flow.
The second major part of the thermal system handles charge-air cooling. The airflow path begins with hot compressed air leaving the turbochargers and entering an intercooler located between the turbochargers and the supercharger. After being cooled there, the air enters the supercharger, then exits the supercharger and passes into a large Whipple aftercooler before finally entering the intake manifold and the intake ports.
For the intercooler circuit, the plumbing uses an inch-and-three-quarter line coming out of the low-temperature radiator and feeding a Stuart EMP inline pump. These pumps are described as stout on their own, but the design allows two pumps to be "Freight trained" together if necessary. Running a pair in series increases both flow and pressure capacity. After the pumps, coolant passes through an inline flow meter, through the intercooler, and then returns from the intercooler in inch-and-a-half line back to the low-temperature radiator.
The aftercooler system is similar in concept but more complex in plumbing because the large Whipple aftercooler has multiple inlets and outlets. It uses the same basic pumping strategy, with one or possibly two Stuart EMP pumps. Coolant leaves the pumps in inch-and-three-quarter line, passes through a flow meter, and then branches into two one-inch lines feeding the aftercooler.
On the outlet side, two one-inch lines leave the aftercooler and merge through a tee into an inch-and-a-half return line. Temperature will be measured into and out of the aftercooler just as it is on the other circuits. Gale notes that the same 8 to 12 degree temperature-change guideline has proven useful here as well. With the engine loop, intercooler loop, and aftercooler loop all instrumented, the truck will carry three flow meters and six temperature sensors in total.
All of those sensors will use Banks instrumentation hardware. The temperature sensors feed into one of the company's four-channel analog modules. The module accepts the sensor inputs through a pre-terminated harness, allowing the sensors to snap into place and connect cleanly to the communication bus.
From there, the data is sent to the Banks iDash DataMonster. The display can show up to eight readings on one screen and supports as many as five pages, each containing between two and eight readings. Beyond functioning as a gauge display, it also serves as a data logger. A microSD card installs below the Banks logo, and the unit can record at up to 20 samples per second for extended periods. According to the explanation, it can log enough data for more than thirty 24-hour Ultra4 races, and it is not limited to cooling information. The system can capture up to 100 channels of data, including engine parameters, turbocharger RPM, temperatures, pressures, flows, and other measurable signals. Logged data can then be reviewed on the device itself or exported from the microSD card to a laptop for charting in Microsoft Excel or other analysis software.
The radiator supplier for the project is Ron Davis Radiators, a company Gale describes with clear respect. He notes that, like Banks, it is a family-run operation spanning three generations. That shared family-business structure is presented as one reason the partnership is a good fit.
The company's history goes back to 1976, when Tony Davis started the radiator business. In 1985, his son Ron bought the company, and by 1990 Ron Davis radiators were being used by top-tier racing teams across many forms of motorsport. That same year, the company committed exclusively to racing radiators. Later, around 2010, Ron Davis significantly expanded its CAD and design capabilities. Because both companies use SolidWorks, they can exchange design information directly over the web, which simplifies collaboration on custom projects like this monster truck cooling package.
By the end of the segment, the cooling hardware is presented as complete and visually impressive, but the real evaluation is still ahead. Before final installation in the truck, the radiators and fan-equipped assemblies will be tested in the dyno cell. That step is important because this application depends on fan-driven airflow rather than road speed, and the system must prove that it can manage the heat load of a supercharged, twin-turbo diesel V8 under those conditions.
The recap closes with anticipation for that dyno validation. The hardware looks finished and professionally built, but the focus remains on whether it performs as well as it appears.