Just got me a used 2022 CAT 259D3 from the local dealer. Long story boring I had a leak on my grapple line while in use and the fluid was red. Checked the tank and its red. Its not a bright red but similar color to the anti freeze. Whenever I bought hydraulic fluid directly from CAT before it was clear. Before I panic is this a different hydraulic fluid or did anti freeze somehow leak in? Unit has 1,600 hours on it. thanks
486-1535 is the red dye I've been known to add. Probably added by your dealer.
Probably original factory hydro oil. Pretty much every new Cat machine I've bought has a red color oil from the factory.
My 265 came with red, Cat oil from dealer is clear.
Thanks guys I called the service department this morning and they also said the factory hydraulic oil has a red color.
It's dyed that way to assist in identifying leak locations. The red colour shows up far better than the almost colourless standard hydraulic oil.
Interesting thread here, I had no clue some hydraulic fluid was dyed.
I think it depends on which plant produced the particular machine but most new ones I have come across have red dye in the hydraulic oil and blue dye in the transmission (for machines that actually have one). We always continued with the dye because it makes leak detection somewhat easier on machines with complex systems.
Having a color sure makes it easier to quickly see in a sight glass. I over filled my excavator one time because you couldn't see the fluid in the sight glass.
Especially with any oil that has little or no colour. Cat Part Numbers are 9U-5031 (Red) and 9U-5032 (Blue). *Obviously other options are available. https://www.petersoncat.com/sites/cat/files/downloads/UV_dye.pdf