GM owner reports coolant leak from quick connector on upper radiator hose.

July 18, 2026 - A General Motors class action lawsuit alleges five models face risks of coolant leaks from the radiator hose quick connectors.

The GM class action covers 2023-2026 Chevrolet Colorado and 2023-2026 GMC Canyon trucks equipped with L3B 2.7L turbocharged four-cylinder engines.

The lawsuit also includes 2024-2026 Chevrolet Traverse, 2024-2026 GMC Acadia vehicles and 2025-2026 Buick Enclaves equipped with LK0 2.5L turbocharged four-cylinder engines.

The lawsuit describes the vehicles as having closed and sealed engine cooling systems where coolant flows continuously between the engines and radiators in contained loops to control engine temperatures and avoid overheating.

Yet the class action states coolant may leak from the radiator hose connectors early in vehicle life and harm the engine.

The General Motors class action was brought by Georgia plaintiff Jonathan Dixon who bought a new 2024 Chevrolet Colorado in March 2024. In February 2026 the check engine light came on with roughly 44,400 miles on the truck, and the plaintiff noticed a metal-on-metal grinding noise at slow speeds.

The dealership identified diagnostic trouble code P3075 and a low coolant level from a leak at the quick-connect end of the upper radiator hose. The plaintiff states he paid $489.36 for repairs.

The class action cites GM's Special Coverage Program N262546590 for lower radiator hose quick connector seals on other models.

General Motors also released Service Bulletin PIT6494A in March 2026 regarding the same upper radiator hose quick connector seal failures on the Colorado and Canyon trucks.

However, the lawsuit claims the bulletin applies only to vehicles still under the three-year/36,000-mile bumper-to-bumper warranty which had expired on the plaintiff's truck. The plaintiff asserts his vehicle has lost value due to the radiator hose problems.

According to the plaintiff, General Motors marketed and sold the vehicles from the start while aware of the radiator hose connector leaks yet still had employees, family members and consumers operate defective vehicles.

The GM radiator hose connector lawsuit was filed in the U.S. District Court for the Northern District of Georgia: Jonathan Dixon v. General Motors LLC.

The plaintiff is represented by Beasley, Allen, Crow, Methvin, Portis & Miles, P.C.