Hydraulic fluid straight from the drum, has a typical cleanliness level of ISO 4406 23/21/18.

A 25 GPM pump operating continuously in hydraulic oil at this cleanliness level will circulate 3,500 pounds of dirt, on an accumulative basis, to the hydraulic system’s components each year!

So to add hydraulic oil, and not the dirt, always filter new oil prior to … Read more

Since 2002 I’ve received a LOT of feedback from my newsletter and blog readers. One question that pops up regularly is: “Why do you give away so much valuable information in your newsletter and on your web sites?”

Well, I spent the better part of 27 years working in and running hydraulic repair shops i.e. rebuilding hydraulic components. During this … Read more

When it comes to hydraulic fluid, it’s not possible to make one, definitive recommendation that covers all types of hydraulic equipment in all applications. But in response to the common question: “What type of oil should I use in my hydraulic machine?”, here are 3 important factors to consider:

Multigrade or monograde?

The operating temperature range of the machine is … Read more