If you’re searching the internet to find out if your car needs a coolant flush, then the answer is most likely yes! Do you have fish swimming in your radiator? Does your coolant overflow bottle look like it’s filled with mud? Even if your coolant is bright and looks clean enough, you may still have scales on your engine block or sludge lurking in your radiator reducing the cooling capacity if your car increasing your chances of overheating.

To learn more about all the different things the coolant, or antifreeze, does in your vehicle, join me, Clark, in the garage where we’ll talk through all the different things antifreeze does besides keep your engine cool.

At the end of the day, it will never hurt or damage your vehicle to perform a coolant flush, so if you’re looking for a good weekend project head down to your local auto parts store and pick up a bottle of BlueDevil Radiator Flush as well as the correct amount and type of engine coolant. If you want to be scientific about the whole process, here are some things you can check.

How to Tell If Your Car Needs a Coolant Flush:

  • Discolored coolant
  • Particles floating in the overflow tank
  • Overheating, either mild or severe
  • High-temperature gradients across heater core or radiator

Discolored Coolant

Coolant comes in lots of different colors but no matter what color your coolant is it should be bright and clear. If your coolant is murky or the color looks muted when you shine a light through it in a clear container then it’s probably time for a coolant flush. Murky coolant indicates it has either been externally contaminated or that it has accumulated wear products.

Particles in the Overflow Tank

Similarly, if you find particles floating in your coolant either in the radiator or in the radiator overflow tank, it is an indication that your coolant isn’t doing a good job inhibiting corrosion or that gaskets are starting to wear out inside your engine’s cooling system and the pieces are floating around in the coolant.  Flushing your cooling system will not only remove these particles but will remove and corrosion products as well which will increase heat transfer.


If your engine is overheating and it has the proper amount of coolant in it, it’s possible that there is simply so much scale and sludge in your system that it is reducing the heat transfer capacity causing your car to overheat under heavy loads. Flushing your system will remove any sludge in your radiator or heater core as well as scale in the coolant jacket in your engine making sure your cooling system as the maximum heat transfer capacity.

High-Temperature Gradients

If there is more than a few degrees difference between in the inlet and outlet of your heater core with your heater on high, then it’s a good possibility that the heater core is actually clogged and very little coolant is running through it. Similarly, if your radiator gets clogged, there will be cold spots in the cooling tubes where the coolant is moving slowly. The best way to check these temperatures is with an infrared thermometer to avoid burns.

If you’re experiencing any of these symptoms head out to the garage as we talk more about coolant flushes!

You can find BlueDevil Radiator Flush at any of our partnering local auto parts stores like:

  • AutoZone
  • Advance Auto Parts
  • Bennett Auto Supply
  • CarQuest Auto Parts
  • NAPA Auto Parts
  • O’Reilly Auto Parts
  • Pep Boys
  • Fast Track
  • Bumper to Bumper Auto Parts Specialists
  • S&E Quick Lube Distributor
  • DYK Automotive
  • Fisher Auto Parts stores
  • Auto Plus Auto Parts stores
  • Hovis Auto & Truck Supply stores
  • Salvo Auto Parts
  • Advantage Auto Stores
  • Genuine Auto Parts stores
  • Bond Auto Parts stores
  • Tidewater Fleet Supply
  • Bumper to Bumper Auto Parts
  • Any Part Auto Parts
  • Consumer Auto Parts

Pictures Provided By:
coolant_flush.jpg – By N_u_T – Licensed by Getty Images – Original Link