The answer isn’t hard, but it is complicated for sure. So it is hard to make a head-to-head comparison and declare an outright better choice. While both Zerex G40 and G12 are high-quality products, they aren’t interchangeable. That’s an easy question to answer in most cases, but not in this one. Which Coolant Is Better Fit For Your Car? So you’ll have to look at alternatives or different brands. The only problem is, the original G12 has been discontinued. G12 goes retails for $7.94-$20.99 depending on the brand. Zerex G40 retails for around $17.99 at Walmart. This is the biggest difference between these coolants. It also has a faster buildup rate, so you’ll have to change it more frequently. Meaning it will either be already late, or there has to be pre-existing rust for it to work. The protection properties only activate when it comes in contact with rust. G12 on the other hand isn’t the best when it comes to protecting the system. So you won’t have to replace it too frequently. G40 doesn’t wear off too fast and the buildup is very slow. They’re made to give you the best of both worlds- better protection against rust and corrosion and a long-lasting service time.Īnd it does both of these pretty well. G12 is pretty far behind in protection properties and needs to be changed more. Zerex G40 gives better rust protection for your car, and it doesn’t need changing much.

Protective properties are more of an added benefit when it comes to car coolants, but it is impressive. So the list of compatible models is pretty short for G12 coolant. G12 is mostly compatible with older car models, it doesn’t go with the newer ones. The upper-temperature limit might be a little lower compared to G40 but the overall range is pretty impressive.

As for summer, it will protect your engine up to 245F. It can protect your engine from winter freezing even at -58F. G12 on the other hand is better for more chilly climates. This coolant is also backward compatible meaning it also works for older models.Įven though the range of older car models is pretty small, the overall model range is pretty good for G40. Zerex G40 is compatible with pretty much all new models but that’s not all. It will protect your engine from winter freezing up to -34F and prevent summer heat issues till 265F. G12 can do better in a broader temperature range but is compatible with fewer models. G40 is better for a warmer temperature range and is compatible with almost all new models. Specs and model range, protective properties and lasting time, price, and availability- these are the major differences between G40 and G12.īoth have pretty solid specs (which is why they’re so popular) but there are definitely some big differences. Key Differences Between Zerex G40 And G12 Coolantīoth coolants are amazing but in a different senses.

Good temperature range supports more engine modelsīetter temperature range supports fewer models A Quick Summary Of The Comparison Feature So which coolant is for your car? Here’s a detailed breakdown to help you out. And putting the wrong one in does more harm than good. Picking the right coolant for your car can be hard especially if you have older models. G12 works better in a lower temperature, has good protective properties, and is more affordable. G40 works better in higher temperatures, has better protective properties, and is pricier. Zerex G40 and G12 are the two most common coolants people use. Coolants, fuels, lubricants- everything is a sensitive issue for your car, especially the coolant.

Audi g12 vs g13 coolant