Just like a car engine needs oil to run smoothly, so too does a gas pressure washer. That’s simply because they need to remain lubricated to work smoothly and efficiently. There are two types of oil that you can use for your gas-powered high-pressure cleaner. You can go for either an All-Purpose Engine Oil which is recommended for temperatures above 40-degreesF or non-detergent pump oil. Non-detergent oils were particularly popular before oil filters became so prevalent. The reason being that they encourage contaminants to stick to the sidewalls of the pressure washer rather than causing a build-up of unwanted sludge or dirty oil. Always check your manufacturer’s handbook first.\r