Don wrote:One of the best things about the DOT 3/4 stuff . . . . he'll know when it goes bad . . . . the color changes - Drastically. It absorbs and mixes with the moisture, and that changes it's color
My 1994 Miata still has it's original brake fluid - 60,000 miles. The clutch fluid has had to be changed 3 or 4 times and both the clutch master and the clutch slave too. I credit the difference (between the fluid life in the clutch and the brakes) to the fact that the clutch master has a small air vent hole in the cap, which allows ambient air to be drawn into it with each push of the pedal . . . . because it's vented, the clutch fluid changes color about every 4 or 5 years . . . . the brake fluid on the other hand still looks like it did when the car was new. The brake master has a huge, unvented rubber bellows atop the fluid so it doesn't draw in any air
There advantages and disadvantages to everything - Like anything else, you pick the one you like the best and dislike the least and go with that. For me, that's always been the 'regular stuff'
If it's original fluid in Ricks 1947 and 1949 trucks......it's probably something much less than DOT 3 or 4. I Googled when DOT 3 came into use, but couldn't find any dates........but I dare say that after 60+ years Rick's trucks brake fluid is quite bad. God only knows how and why the trucks brakes work at all for they should have seized up decades ago.
Yes, brake systems need to be vented, but they are sealed against the atmosphere via a rubber bellows that sits right under the cap on every master cylinder.
I agree with you Don....... there are advantages to everything it seems, but for our X's that sit and sit for months and sometimes years, unless you change-out the brake fluid every 2--3 yrs, then internal master cylinder and caliper corrosion will develop especially if the bikes are kept in a un-controlled environment. Even my X's that are kept in a/c and heated garage corroded in 4 yrs.
Frankly, I'm beginning to think that the lack of use plus no change-outs lets things corrode quicker than if the bike is used so things get moved in the brake system.
So you haven't changed your Miata's brake fluid in 17 years ? Wow
Maybe someone put DOT 5 in it.