Using high-grade compressor oil guarantees the durability of both the compressor and the vehicle’s entire air conditioning system. When selecting this oil, a workshop can choose to juggle a host of different types and different viscosity classes. Or it can pick just one: the multigrade lubricant, PAO 68 oil from MAHLE. One product for (almost) all compressors, types of drive, and refrigerants

No more tricky decisions

Here’s the good news, right up front: PAO 68 oil from MAHLE (AA1 and AA3 versions) can be used safely and reliably as a lubricant in all air conditioning compressors. It’s been tested by the manufacturer and by independent institutes, meets the highest standards, and has absolutely no negative effects on components in either the vehicle air conditioning system or the air conditioning service unit.

You can use the AA1 version of our PAO 68 oil (without leak detecting agent) in almost all air conditioning systems in vehicles with a combustion engine or an electric or hybrid drive. Plus, it’s suitable for both R134a and R1234yf refrigerants as well as for conventional piston and electric compressors. It’s an oil for any situation.

Vane compressors are the only type AA1 can’t be used for. But don’t worry, our range also includes a compressor oil that is suitable here—the AA3 version.

The trouble with conventional oils

xR134a and R1234yf refrigerants, belt-driven and electric air conditioning compressors: any vehicle workshop that continues to use conventional compressor oils like PAG and POE will have the none-too-easy task of coping safely with three or four oil types for both refrigerant options and all the different compressor variants.

We all need to be clear about one thing: by the time the first vehicle with an e-compressor arrives in the workshop, the different types of oil must be kept completely separate. That’s because the oil used in an electric compressor must not be hygroscopic or electrically conductive. If conventional PAG and POE oils are mixed, this produces an oil with reduced insulation capacity, which can cause a short circuit in an electrically driven compressor (+200 volts). There is also a risk of the blended oil degrading and thus losing its lubricating properties.

Of course, we do also offer PAG oils if you want to use them: in all viscosity classes, for R134a and R1234yf refrigerants, and for conventional as well as electric air conditioning compressors.

Did you know?

MAHLE is one of the world’s leading original equipment manufacturers for engine cooling and automotive air conditioning. Because we are full-line suppliers in the area of thermal management and have extensive original equipment competence, we can provide you with all-round support. With us, you also benefit from 30 years of experience in A/C service and our comprehensive range of information and services. Everything from a single source—you’ll only get that from MAHLE!


What makes our PAO oil so good?


During manufacture, special additives are added to the base PAO (polyalphaolefin) that give the oil outstanding characteristics. PAO 68 oil from MAHLE is a combination of highly refined synthetic oil and performance-enhancing additives. This means that our multigrade oil has certain advantages that make it suitable for a variety of applications. For example, in contrast to PAG oils, it isn’t hygroscopic—i.e., it doesn’t absorb any moisture from the ambient air and can therefore be kept in stock without any difficulty. And not only is that convenient, it’s also more cost-effective for you.

Thanks to its nonhygroscopic nature, this oil can also be used to prevent and counteract problems with humidity in the vehicle air conditioning system, such as the icing up of components or the formation of acids in the air conditioning circuit.

In addition, PAO 68 oil is compatible with many other lubricants and refrigerants. When used in combination with PAG oil and refrigerants, it can be mixed with other oils as required, but only to a certain extent. Its molecular structure and density cause it to separate out again when it settles. This means that PAO 68 oil doesn’t form permanent bonds, the necessary viscosity of the individual oils is maintained, and there is no change to their overall viscosity. So, you can use PAO 68 oil to both top off and change the system’s entire oil volume.

Plus: an added bonus

In its range of multigrade oils, MAHLE also offers a version that contains fluorescent contrast agent for UV leak detection. PAO 68 Plus UV oil has the same positive characteristics as PAO 68 oil. In fact, the admixture of a small quantity of contrast agent maintains these advantages and avoids negative effects on system components or service equipment.

You don’t have to take our word for it—we’ve had this tested by independent institutes too! All the results were positive, demonstrating that the contrast agent had no negative effects. That means you can add our PAO 68 Plus UV oil directly to a component (such as a compressor) or introduce it into the refrigerant circuit via the air conditioning service unit.

Our PAO 68 Plus UV oil is not suitable for systems using R1234yf, for vane compressors, or for electrically driven air conditioning compressors.

Other useful characteristics:

  • No oil collects in the evaporator, so there’s no associated deterioration in cooling performance
  • The oil film in the components improves the seal
  • Less friction between the components
  • Lower energy consumption by the compressor
  • Extensive operating range (–68°C to 315°C)

Product overview



We regularly provide technical tips relating to the powertrain, thermal management, and mechatronics in automobiles.


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