Performance Radiator for Hummer H3 H3T (2006-2010)

High-Capacity Aluminum Radiator for 2006-2010 Hummer H3

Designed for high-stress applications, this 3-row aluminum radiator replaces the restrictive and crack-prone factory unit to significantly lower coolant temperatures during off-roading or towing.

The Stock GMT345 Cooling Shortcoming

The factory Hummer H3 cooling system relies on a single-row core paired with crimped plastic end tanks. Over time, continuous thermal cycling degrades the plastic and rubber gaskets, leading to microscopic stress fractures and catastrophic coolant leaks at the factory seams. Furthermore, the OEM core lacks the volumetric fluid capacity necessary to mitigate severe heat soak when the vehicle is subjected to low-speed, high-load off-road conditions or when towing over steep grades. As the Atlas L5 or LS V8 engines build heat, the restrictive factory fin density fails to reject BTU loads efficiently, causing temperature gauges to spike and putting head gaskets at severe risk of failure.

The Engineering Solution

This performance replacement utilizes a fully TIG-welded, brazed core construction crafted entirely from aircraft-grade AA5052 aluminum. By eliminating plastic tanks and upgrading to robust 2mm thick aluminum end tanks, the risk of seam failure is completely eradicated. The high-density tube and fin architecture expands into a 3-row, 44mm thick racing core, dynamically increasing the surface area and overall fluid volume. This structural upgrade translates to a 35% to 45% improvement in thermal dissipation capability. Integrated into the bottom tank is a CNC-machined transmission oil cooler, ensuring that extreme drivetrain loads are kept within safe operating parameters, even under intense off-road stress.

Technical Specifications

Compatibility

• 2006 Hummer H3 3.5l L5
• 2007 Hummer H3 3.7l L5
• 2008 Hummer H3 3.7l L5
• 2008 Hummer H3 5.3l V8
• 2009 Chevrolet Colorado 5.3l V8
• 2009 GMC Canyon 5.3l V8
• 2009 Hummer H3 3.7l L5
• 2009 Hummer H3 5.3l V8
• 2009 Hummer H3T 3.7l L5
• 2009 Hummer H3T 5.3l V8
• 2010 Chevrolet Colorado 5.3l V8
• 2010 GMC Canyon 5.3l V8
• 2010 Hummer H3 3.7l L5
• 2010 Hummer H3 5.3l V8
• 2010 Hummer H3T 3.7l L5
• 2010 Hummer H3T 5.3l V8
• 2011 Chevrolet Colorado 5.3l V8
• 2011 GMC Canyon 5.3l V8
• 2012 Chevrolet Colorado 5.3l V8
• 2012 GMC Canyon 5.3l V8
• Compatible with both Manual and Automatic Vehicles

The Hummer Off-Road Standard

Whether you are crawling through technical trails in the desert or hauling gear on the highway, maintaining optimal operating temperatures is critical for the GMT345 platform. This all-aluminum radiator provides the structural durability and thermal headroom required for sustained high-load environments, preventing catastrophic overheating events miles away from civilization.