Upgrade an aging, cracked, or leaking plastic coolant reservoir with a one-piece cast aluminum replacement designed to replace two common GM OEM reservoir designs in one durable assembly.

Factory plastic coolant reservoirs may become brittle, crack, or deform after years of repeated heat cycles. This heavy-duty aluminum coolant reservoir provides improved strength, heat resistance, and long-term reliability while maintaining the original hose connections and mounting configuration when properly matched to the vehicle.

Designed to replace compatible 603-054 and 603-973 style coolant reservoirs, this aluminum expansion tank fits select 2007-2020 Chevrolet Silverado 1500/2500, Tahoe, Suburban, Avalanche, GMC Sierra 1500, Yukon, Yukon XL, Cadillac Escalade, Escalade ESV, and Escalade EXT applications.

Compatible replacement numbers include:

603-054, 603-973, 22870828, 22856231, 15833723, 22797286, 84368363, 84368362, 13502353, 13502354, GM3014134.

Features:

One-piece cast aluminum construction

Replaces two common GM coolant reservoir configurations

Resistant to cracking, heat aging, and deformation

Direct replacement design with factory-style mounting points

Includes 21 PSI / 145 kPa pressure cap

Package Includes:

1 × One-Piece Aluminum Coolant Reservoir

1 × 21 PSI / 145 kPa Pressure Cap

Important:

OE numbers are provided for compatibility reference only. Please verify OE number, hose connections, mounting points, pressure cap requirements, and reservoir appearance before purchase. Vehicle fitment may vary depending on model year, engine, and original reservoir configuration.

On Sep 16, 2026 at 06:26:04 PDT, seller added the following information: