1990 GMC Rally Wagon 3500 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1990 GMC Rally Wagon 3500
1990 GMC Rally Wagon 3500 Problems
The intake manifold gasket may develop and external engine oil or coolant leak. In some cases, an internal coolant leak may occur causing coolant to mix with the engine oil. Running the engine with a coolant/oil mix may result in engine damage. Replacing the intake manifold gasket should correct this issue.
A coolant leak may develop from the water pump. This can result in an engine overheating condition. A leaking water pump will require replacement.