A-Premium Radiator Coolant Expansion Tank with 15 PSI Cap & Sensor — Direct-Fit for GM Trucks and SUVs

The A-Premium Radiator Coolant Expansion Reservoir Overflow Tank is a direct-fit replacement coolant recovery tank that includes a pressure cap and sensor for compatible GM trucks and SUVs.

This replacement overflow tank is designed to restore proper coolant containment and pressure regulation in older GM full-size trucks and SUVs. Molded from heat-resistant PA plastic and supplied with a spring-loaded 15 PSI cap plus a sensor and tubing, it helps maintain the vehicle's cooling system performance after the original tank becomes cracked, leaky, or sensor-faulty. The unit is engineered as a direct-fit service part for many Cadillac, Chevrolet, GMC and Hummer models from the late 1990s through the 2000s.

Which vehicles will this reservoir fit?

Compatibility covers a wide range of GM platforms—mainly full-size pickups and SUVs produced between the late 1990s and mid-2000s. Before ordering, confirm your exact year, make and model against the reference numbers provided to ensure fitment.

• Cadillac Escalade 2002–2006
• Chevrolet Avalanche 1500 / Silverado / Suburban / Tahoe 1999–2006 (varies by model)
• GMC Sierra / Yukon / Yukon XL 1999–2006 (varies by model)
• Hummer H2 2003–2009

How does it restore proper cooling system function?

The replacement tank returns the cooling system to its designed expansion and recovery behavior, preserving coolant volume and allowing the system to vent and reclaim fluid as temperatures change. The included 15 PSI spring-loaded cap helps maintain correct system pressure while the sensor provides a signal for level monitoring or warning lights.

• Pressurized design rated to 15 PSI for proper system sealing
• Includes cap, sensor and tubing for a complete swap
• Two mounting holes for secure OEM-style installation
• Sensor restores level/diagnostic feedback to the vehicle

What materials and build details should I expect?

The tank is molded from durable PA (polyamide) plastic chosen for thermal stability and vibration resistance under engine-bay conditions. The assembly ships with matching components to minimize additional purchases and simplify the repair job.

• Heat-resistant PA plastic construction
• Spring-loaded twist cap type for reliable sealing
• Includes one reservoir, one cap, one sensor, and one tubing piece
• Two pre-drilled mounting points for straightforward replacement

How do I confirm this is the correct part for my truck?

Compare the listed reference numbers and the vehicle fitment list with your vehicle’s year, make and model. Use the seller’s "Year/Make/Model" selection tool or consult your service manual to verify compatibility before purchase.

• Reference numbers: 603-102, 19353731, 10188034, and others
• Confirm fit via the Year/Make/Model selector or part lookup
• Inspect mounting hole count and cap style against the old tank
• Contact the seller with VIN or part number for final verification

Who is this for: This A-Premium coolant reservoir is intended for owners, DIY mechanics and professional shops replacing aged or damaged coolant expansion tanks on compatible Cadillac, Chevrolet, GMC and Hummer models. It's a practical choice when the original tank leaks, the level sensor fails, or the cap no longer holds pressure. Technically inclined buyers will appreciate the included sensor, cap and tubing that let you complete the repair in a single purchase, while shops benefit from a direct-fit aftermarket option covered by a one-year unlimited-mileage guarantee.