Old fluid gets real nasty looking, and with the plastic reservoirs you can see it now, where before you could not with the old iron master cylinders.
Its always been a hassle to find someone to help bleed brakes so finally, last year, I bought a pressure bleeder kit in
preparation for new brakes on the RAM. To test out the new
Mityvac MV7840 Pressure Brake Bleed Kit for Pressure Bleeding Hydraulic Brake and Clutch Systems, I tried it out on my Pontiac Vibe, just to learn the peculiarities of this pressure bleeder (I have never used one before). The fluid that came out looked pretty good for being 20 years old.
Then I did the RAM so the system would have clean fluid and I would not contaminate the calipers or new hoses when I did the brakes. That too went well, and the old fluid was most likely original (20 yo) and very, very dark and nasty. After doing the brakes I again bled the system and now I have brand new fluid in all the vehicles. (My Ranger got a complete bleed a couple of years ago after the antilock module started leaking and was replaced).
I have always been a believer in fresh brake fluid, it was just too much trouble before I bought the pressure bleeder.
If you have a European car with DOT4, that fluid is even worse about sucking up moisture so you need to heed the flush requirements.
The pressure bleeder has two issues and that is, 1) you use a lot more fluid with it (which has become very expensive), even when I pour the unused fluid back in its original bottle (which I date when I opened it) and 2) cleaning it up is a hassle, as they call for Denatured Alcohol, which is expensive, and I have to run that thru everything to flush the fluid out of hoses and couplings. Lots of wiping and cleaning.
Charles