To back up Jeff Scott's assessment. I work on commercial jets. The 5606 in our struts will turn brown and will suspend micro bubbles that won't seem squishy until you change the fluid. Remarkable difference.
Adam Tippin A&P KR2S builder > If all is well there, drain and replace the 5606 hydraulic fluid. I have > worked on 1 plane that needed to have the hydraulic changed in the brakes > every 10 years or so. It would degrade and turn a to a dark brown. Brakes > also didn't work very well until the fluid was replaced when it looked like > that. > > -Jeff Scott >
