Need to change my brake fluid. Any specific steps I should be aware of? Also, what fluid is the best to use. I have the GT5 brakes on my 1974 Pantera.
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Nope, nothing special. A Mitey-vac allows you to suction more of the rear reservoir fluid out, so you'll need to chase less new fluid through the system to get clean stuff out the bleeder screws. DOT- 4 fluid is the best available for the street, but Ford DOT-3 is used by lots of racers. The difference is, Ford DOT-3 tends to pick up water from the atmosphere a little faster than Dot-4. Both have exceptionally high boiling points when new. Real-racers change their fuid before each event so the water increase with Ford DOT-3 is not significant. I'd stay away from silicones of all types. And while you're in there, change fluid in the clutch master too. Same things apply. When bleeding each wheel (or the clutch slave), remove each bleeder needle and wrap the threads with a couple of turns of teflon tape; be sure the bleed hole is clear. When bleeding, air can be sucked in around the needle threads, so it looks like you've got lots more air in the system than is real. A real time-saver.
Also get yourself a manual vacume pump form Pep Boys so you can bleed at the wheel by yourself. It could save your marrage, otherwise the wife may have to pump at the pedal.
Jack, why stay away from the silicones? is it the extra compressability?
RSD - When you do change your fluid be very careful not to get a DOT 3 or 4 on your painted surfaces. They WILL lift your paint! one advantage of the silicone fluids is they will not.
RSD - When you do change your fluid be very careful not to get a DOT 3 or 4 on your painted surfaces. They WILL lift your paint! one advantage of the silicone fluids is they will not.
Silicone fliuds are more viscous than mineral oil, so its extremely hard to bleed air out of them. Microbubbles stay in forever seemingly, which may be the cause of its altitude sensitivity. A well-publicised rod-run to Big Bear Mountain in So-Cal took place quite a few years ago, and almost every car with silicone fluid lost its brakes at 7000 ft of altitude. After being flat-bedded at great expense back to L.A, the brakes miraculously returned.... A few classic cars that used silicone fluid found that water still gets in the lines but does not mix, when the water froze while the car was stored in an unheated garage, and split a line. Finally, consider: not one racing association approves silicones and a few absolutely prohibit it's use. Even pro-racers stay away, and if there were ANY advantage, the guys that race for money would've found it in the 35+ years its been around. All this is too high a price to pay so I don't have to change brake or clutch fluid yearly, IMHO