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Which RV antifreeze is best?

If you own an RV, it’s vital that you understand how to use RV antifreeze. As RVs continue to rise in popularity, there are a growing number of RV antifreeze brands to choose from, but which one is best? Splash RV/Marine Antifreeze is both popular and effective. Still, there are many other RV antifreeze brands out there that can get the job done.

What to know before you buy RV antifreeze

RV antifreeze vs. automotive antifreeze

Automotive antifreeze is typically incredibly toxic and used in your engine’s cooling system. As temperatures change from hot to cold, automotive antifreeze helps regulate your engine’s temperature and prevent corrosion. Alternatively, RV antifreeze is a non-toxic substance that keeps your RV’s plumbing system from freezing in cold temperatures. 

It’s incredibly important that you never attempt to use automotive antifreeze in your RV’s plumbing system, as the fumes could be fatal to you and your family. Likewise, you should never attempt to use RV antifreeze in your vehicle’s engine, as it may damage your vehicle.

How to winterize an RV

  1. Drain and clean your black and gray tanks: The first thing you’ll want to do is make sure your black and gray tanks are empty and as clean as possible. Leaving wastewater in your tanks will allow bacteria to proliferate and increase the chances of water freezing in your tanks.
  2. Flush and drain your water heater: Turn your water heater off and allow it to cool down and depressurize. You’ll want to hook up your city water connection but leave the water turned off. Open the pressure-relief valve after removing the drain plug and anode rod. After the water drains from the water heater, turn your city water on and allow it to flush for 2-3 minutes.
  3. Locate the water heater bypass: You’ll want to ensure you don’t add antifreeze to your water heater. In some cases, your RV may have a water heater bypass installed. In other cases, you’ll have to locate your water heater service door and line it up with where it feeds inside.
  4. Drain your fresh water tank and locate the water pump: Make sure your water pressure is off and drain your fresh tank. Attach your siphoning kit to your water pump and put the siphoning hose in your RV antifreeze jug. Turn the water pump on.
  5. Open external and internal faucets and valves: Begin opening your external valves. Allow the water to drain until it turns pink. Repeat this process for your internal sinks, showers and toilet.
  6. Add extra antifreeze: Pour extra antifreeze down your sinks, shower and toilet. Ensure that your water’s heating element is turned off and your faucets and valves are closed.

Professional RV winterization

If you don’t want to winterize your RV yourself, you can always pay a professional to do it for you. Many RV dealerships will winterize your RV for you for a fee. If you prefer to have a professional winterize your RV, give your local RV dealerships a call to see if they offer winterization services.

What to look for in quality RV antifreeze


Some RV antifreeze brands charge exorbitant prices for their fluid. However, most RV antifreeze costs between $15-$30 a gallon and are more than adequate to get the job done. 

Bulk buying

With around four gallons of RV antifreeze, you can winterize your RV or trailer for two winter seasons. When buying RV antifreeze, consider buying two or four gallons at a time, as they will likely be cheaper per gallon.


Most RV antifreeze can be used in swimming pools or marine vehicles as well as your RV. If you want to get the most bang for your buck and own a boat or swimming pool, it’s a good idea to buy RV antifreeze that has multiple uses.

How much you can expect to spend on RV antifreeze

Most RV antifreeze costs around $15-$30 per gallon. If you buy RV antifreeze in bulk, you can expect to pay around $12-$17 per gallon.

RV antifreeze FAQ

How much RV antifreeze do you need to winterize your RV?

A. You typically need about 2 gallons of RV antifreeze for a 50-gallon tank.

Do I need to winterize my RV if I live in it through the winter?

A. No. If you completely winterize your RV while living in it, you won’t be able to use your sink or shower. If you’re living in your RV in a winter climate, you’ll likely turn your heat on throughout the day and maybe even install RV skirting, which will make your pipes less susceptible to freezing.

What’s the best RV antifreeze to buy?

Top RV antifreeze

Splash RV/Marine Antifreeze

Splash RV/Marine Antifreeze

What you need to know: This RV antifreeze is great for RVs, swimming pool systems, vacation homes and spas. 

What you’ll love: Splash RV antifreeze is popular and effective. This RV antifreeze features -50 degrees burst protection. 

What you should consider: You can’t purchase this RV antifreeze in bulk.

Where to buy: Sold by Amazon

Top RV antifreeze for the money

RecPro RV Antifreeze

RecPro RV Antifreeze

What you need to know: This nontoxic RV antifreeze comes in sets of two or four gallons. 

What you’ll love: RecPro’s RV antifreeze features -50 degrees burst protection. A two-pack of this RV antifreeze is enough to winterize most RVs completely. This RV antifreeze can also be used in marine vehicles and swimming pool systems.

What you should consider: Even in a two-pack or four-pack, this antifreeze is on the pricey side.

Where to buy: Sold by Amazon

Worth checking out

Peak RV and Marine Antifreeze

Peak RV and Marine Antifreeze

What you need to know: Peak is a trusted brand in RV and automotive antifreeze.

What you’ll love: Peak’s RV antifreeze is safe for use in brass, metal, copper and non-acetate plastic pipes. This antifreeze can be used in RVs and marine vehicles.

What you should consider: Some users found that this antifreeze froze at temperatures less than 4 degrees.

Where to buy: Sold by Amazon


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Cody Stewart writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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