Q. We have a 2001 Dodge Ram 2500 with a V-10 engine that loses about one gallon of antifreeze every 600 miles. The dealer has been unable to find the problem, even after checking with dye in the system. We do not smell any antifreeze while driving or after stopping, and have not found any drips or leaks. What could be wrong?
— S.K., Pevely, Missouri
A. The coolant has to go somewhere — either on the ground, into the oil, sucked into the engine’s combustion chambers and out the exhaust — or it might evaporate after leaking externally onto hot parts while the engine is running. Don’t overlook the radiator and heater core. You should take it to another shop where a thorough pressure test and another dye test could be performed.
One gallon every 600 miles is a lot; too much to go undetected. Often, stains remain where coolant has seeped and then evaporated.
Ken Freund’s more than three decades of auto-repair experience and 20-plus years of RVing helped him author numerous books and articles on vehicle repair. In addition to RV Clinic and Performance, he writes the Powertrain column in MotorHome magazine. Ken has been a California Automotive VO-Tech and Smog-Test Program Instructor and an ASE-certified Master Automobile Technician.