i have done an initial brake check of my 75 valiant. it has 63k on it, and it sat for a very long time before i got it.

the front calipers appear to be okay, the pads are still within acceptable wear. the front hoses look old and will be immediately replaced, as will the rear hose.

the wheels look like they've never been removed (although they must have been, based on the various tire sizes). the lug threads are flawless, the nuts look literally new, and on the rear drums the area where the wheel touches the drums IS STILL SHINY (unlike the remainder of the drums themselves, with the expected rust). shoes look very good, and a few shots of brake clean reveals what appears to be outstanding condition of brake hardware. no signs of any fluid loss (ever) from wheel cylinders. shoes are 10x2.5.

i stomped on the pedal long and hard, and have noticed some seepage from the top of the master cylinder. very slight loss of pedal, but only once. fluid level still good.

gentle test drive around the block a few times revealed a pulsing feel, making me wonder if i have a warped rotor or if it is surface rust?

PLAN: new master cylinder, new hoses, hone and kit wheel cylinders, flush system with new fluid. have rotors checked for trueness, service wheel bearings.

QUESTIONS: i wouldn't be surprised that this could be the original fluid, which would have been DOT3. is it compatible with DOT4, which is most readily available where i live? how do you know when you've got it all out? should i consider switching to DOT5, pros and cons? have i missed anything?

I'd like to warn you that many of the name-brand (Bendix, Wagner) hydraulic brake parts I've gotten lately have been made in China, don't fit well and aren't well made. The rebuilt (Bendix, Pronto/Cardone) parts were terrible and required rebuilding again. The Centric and Con-Seal new parts from have all been US made and I've been pleased with them; I got everything from Rockauto.

While I'd suggest you open everything up for inspection, the poor quality of many of the replacement parts today may mean you'd be much better off reusing everything you can.

I'm from the rust belt and fought rust inside the hydraulics for years; then
I carefully switched most of my cars (garage queens and daily drivers) to DOT5 many years ago (replacing all the hydraulics at the time) and never changed the fluid since and had no trouble with it - the pedal felt firm and they work fine. For my next car, though, I'm considering DOT4 or DOT5.1 and just plan on flushing it every 2 years. DOT3 and DOT4 is pretty cheap compared to DOT5.

I wouldn't switch to DOT5 unless you change every single seal, and the low quality of parts (many warranties are void with anything other than DOT3 or 4), and the fact DOT5 can be hard to find, seems to make a DOT3 to DOT5 conversion much more challenging now than it used to be.

It's possible I've just had a run of bad luck, but I'd suggest you avoid questionable (esp. Chinese & Italian) brake parts, even with brand names on the box.

helpful info. thanks!