Must-Read: Volkswagen Coolant Guide

When it comes to vehicle maintenance education, engine coolant doesn’t get as much attention as motor oil and transmission fluid, but it’s just as important. The more attention you give your coolant, the longer your engine and its components may last.

Pouring coolant

Photo credit: Moody Air Force Base

The Importance of Coolant Maintenance

Even though coolant is a low-maintenance fluid, it still needs some attention from time to time. More specifically, it needs to be changed and checked periodically.

1. Changing the Coolant

Engine coolant deteriorates over time and can cause acid buildup, loss of resistance to freezing and boiling points, and engine overheating. That’s why most mechanics recommend changing it every 40,000-50,000 miles or every 3-4 years, whichever comes first. A lot of car owners like to kill two birds with one stone by flushing their coolant system at the same time as their timing belt replacement.

2. Checking the Coolant Concentration

To prevent your engine from overheating in the summer and freezing in the winter, check your coolant concentration on a semi-regular basis. A good rule of thumb would be to check it every time the seasons change, as well as a few times in between.

Here’s a good tutorial on checking the coolant concentration. If the coolant is weak, flush your coolant system and put in new coolant as soon as possible because a weak concentration can lead to water pump failure and other problems in the system.

It’s important to note that you should only use distilled water when diluting the coolant. Never mix tap water and coolant.

Which Coolant to Use

Like all things Volkswagen, the Volkswagen engine is of premium quality. That's why you need to use VW-approved G11, G12, or G13 coolants, as they are anti-phosphate, anti-amine, and anti-phosphorous.

To find out whether you should use G11 or G12 in your VW, check your owner’s manual or look at your expansion tank. G13 coolant, available in vehicles made after 2008, can be used in almost every VW vehicle. It’s considered superior to G11 and G12 because it’s eco-friendly, has better freezing and boiling points, contains premium corrosion protection additives, and has high flow characteristics.


What Happens if You Use the Wrong Coolant

Using ordinary coolant not specifically made for Volkswagens can lead to all kinds of problems, including:

  • The corrosion of metal, rubber, and plastic components in the cooling system
  • Deposits building up in the radiator core
  • Restricted coolant flow, which eventually leads to serious engine problems

This is because ordinary coolant doesn’t contain the properties needed to function optimally in a Volkswagen engine. Some store-bought coolants contain ethylene glycol, which will wreak havoc on your VW’s coolant system.

Have any VW coolant-related questions that aren’t addressed in this post? Email us or hit us up on Facebook. We’ll be happy to answer your questions!