This past winter I started getting a lot of pump noise, that typical whine, especially in really cold temps. Also when cranking the wheel I was getting some bad groaning sounds. I assumed I was ready for a new pump and have been waiting for warm weather to deal with it.
So today I went and picked up a new pump and got the puller tool. I wanted to start with a flush to get all the old fluid out of the system.
I disconnected the return line from the reservoir and put it in a jug to catch the old fluid, then siphoned all the old fluid from the reservoir. I proceeded to run three quarts through until it was running clean, while operating the brakes and turning the wheel lock to lock. The fluid that came out initially was really nasty: black, burnt and sludgy. No metal particles though. Chances are it was the original fluid with 160k.
When I got done flushing it was running really quiet so I went for a ride and did some hard turns and it seems totally cured. My question is what's the chance that fresh fluid took care of my problem and my pump is actually okay. Or is the pump likely damaged and needs replacing anyway? I'm hoping no particles in the old fluid was a good sign.









