When incompatible lubricants are mixed, there will be adverse side effects. Many of today’s premium lubricant formulations have new risk factors related to lubricant cross-contamination.
Lubricants need to be compatible not only with other lubricants, says Brown of Amsoil, but also with seals and components to ensure long seal life.
All engine oils today have to be compatible with both synthetic and conventional products, says Lucas Oil Products’ Gutiérrez. “When you get into more specialized lubricants, such as automotive air conditioner compressors and high dollar stationary compressors, you have to be very aware of your product selection. In automotive air condition compressors, for example, polyalkylene glycols (PAG) have been used as air conditioner lubricants but are incompatible with mineral oils. Mixing the two together will result in a significant increase in the viscosity of the lubricant and in some cases solidification.”
An easy way to explain synthetic and conventional compatibility is to use the engine oil as an example, says Currie of Justice Brothers. “If you are using 100 percent synthetic oil in your engine and had to add a few quarts of conventional oil in a pinch, you would end up with be a semi-synthetic.”
There is no problem in brand compatibility either, he says. “While one oil brand might be better than another, by mixing the two you end up with oil that is neither as good as the quality oil you added and not as bad as the lower quality oil you added.
“For the most part, lubricant compatibility may not be a problem. But with that being said, due to today’s more sophisticated systems, you need to check the manufactures specifications,” Currie suggests.
“Compatibility in greases is important because some greases are not compatible with other greases and some are only compatible with themselves and any other type of grease should not be used,” says Mackenzie of Omni Lubricants. “Therefore, it is important for the end user of the grease to first find out what type of grease they are using now and then check to see if the proposed new grease is compatible with it.”
When it comes to selecting lubricant suppliers, Amsoil’s Brown says choice should be based on lubricant performance and suggests researching available products, requesting documentation of the product’s performance claims and running field trials with different lubricants to determine the best option.
Make sure that the lubricant supplier has a good reputation in the industry and stands behind the performance of their products,” says Gutiérrez of Lucas Oil Products. “You also want to make sure that pricing is competitive and that they can consistently supply product without delays or interruption.”
Omni Lubricants’ Mackenzie adds: “It is important to find products that will save time and money and a supplier with a long history of successful application experience in the toughest applications other than automotive type applications.”
The length of time a particular lubricant manufacturer has been in business and the value of products and quality of service are other important considerations, says Justice Brothers’ Currie. “Also, while it may be a dying breed, personal service is an added value and can save you considerable money over years of a relationship.”
“It also helps you to find out what others in your particular type of usage are doing. It’s a forgotten benefit that can really pay-off.”
Don’t forget to also consider the services offered by the supplier, including local distribution and support for technical and applications questions.
After making sure an ATF meets the specific requirements instructed for a vehicle, another question that might be asked is whether to use synthetic ATF or petroleum ATF.