can u use rv antifreeze in cars

[Wendy]

No, you should not use RV antifreeze in your car's cooling system. While both products are called "antifreeze," they are formulated for entirely different purposes and are not interchangeable. Using RV antifreeze in a car can lead to serious engine damage due to inadequate heat transfer and corrosion protection.

The primary function of automotive antifreeze, or engine coolant, is to regulate engine temperature by transferring heat away from the engine block. It also contains a sophisticated package of anti-corrosion additives (corrosion inhibitors) that protect the various metals (aluminum, cast iron, copper) and materials (rubber, plastic seals) inside a modern car's engine. RV antifreeze, designed for potable water systems and winterizing plumbing, lacks these critical high-temperature additives. It is not engineered to withstand the extreme heat and pressure of an internal combustion engine.

Using RV antifreeze can cause several problems:

• Overheating: It has inferior heat transfer properties compared to automotive coolant, leading to inefficient cooling and potential engine overheating.
• Corrosion: The lack of proper inhibitors can cause rapid corrosion of the water pump, radiator, heater core, and engine head gasket. This corrosion can lead to leaks and costly repairs.
• Damage to Seals and Hoses: The chemical composition may degrade engine seals and hoses over time.

The following table compares typical properties of the two products, illustrating why they are not compatible:

Property	Automotive Antifreeze (OAT Formula)	RV/Marine Antifreeze (Propylene Glycol)
Primary Function	Engine cooling & corrosion inhibition	Winterizing water lines; non-toxic
Heat Transfer Efficiency	High (designed for > 200°F/93°C)	Low
Corrosion Inhibitors	Complex package for metals & seals	Minimal to none
Boiling Point (50/50 mix with water)	~223-265°F (106-129°C)	Significantly lower
Freezing Point (50/50 mix with water)	~ -34°F (-37°C)	~ -26°F (-32°C)
Common Base Fluid	Ethylene Glycol or Propylene Glycol	Propylene Glycol
Toxicity	Ethylene Glycol is highly toxic	Generally less toxic

Always use an antifreeze that meets your vehicle manufacturer's specifications, which are listed in your owner's manual. Mixing the wrong types of coolant can also be detrimental. If you accidentally used RV antifreeze, it is crucial to flush the entire cooling system thoroughly and refill it with the correct automotive coolant.

[McRobert]

Absolutely not. It's a quick way to ruin your engine. Think of it like this: RV antifreeze is for pipes, car coolant is for a high-performance engine. Your car's cooling system is a brutal environment with extreme heat and lots of different metals. RV antifreeze doesn't have the protective chemicals to prevent corrosion. You'll end up with a corroded water pump and a leaking radiator, which is a much bigger bill than just buying the right jug of coolant from the auto parts store.

[AlexandraDella]

I learned this the hard way. My neighbor used RV antifreeze in his old truck one winter, thinking he was saving a few bucks. Within a few months, the heater core was shot, and the radiator had a nasty sludge building up. The mechanic said the antifreeze basically offered zero protection and let everything corrode from the inside. It cost him over a thousand dollars to fix. Just stick with what the car manual says. It's not worth the risk.

[LeAdriel]

As a mechanic, I see this mistake more often than you'd think. The key difference is in the additive packages. Automotive coolant has specific inhibitors for aluminum, which is what most modern engine blocks and heads are made from. RV antifreeze has none of that. It's like putting dish soap in your dishwasher; it might make bubbles, but it doesn't have the right ingredients for the job. Using the wrong fluid can silently destroy your cooling system components long before any visible symptoms appear.

[LaBlakely]

It's a definite no. While both liquids may look similar and prevent freezing, their jobs are completely different. Your car's engine coolant operates under intense pressure and heat, requiring advanced formulas to prevent corrosion on sensitive components like the aluminum radiator and water pump. RV antifreeze is not formulated for these conditions. Its use would likely lead to premature failure of the water pump and clogging of the radiator with corrosion byproducts, causing the engine to overheat. Always refer to your vehicle's owner's manual for the correct type of antifreeze to use.