K Charles wrote:
When a line "blows" only half the brakes quit with a duel master cylinder and your trailer brakes will stop the trailer. Thanks to Ralph Nater your family wasn't in danger unless you were going to fast.
Umm.. You better go take a good hard look at your master cylinder, PRONTO.
What you posted may have been true back in the 1990s and before where the MC had TWO SEPARATE RESERVOIRS (one for front and one for the back).
Modern day master cylinders still have two separate hydraulic circuits but they SHARE the fluid reservoir (old dual MCs had a partition in the reservoir new ones do not)!
What that means is you blow a line (either front or back) you only get a FEW PUMPS of the brakes and then you have NOTHING since the bad line will drain ALL of the fluid out of the single reservoir.
I ran into this a few years ago when my 2003 F250 blew a rear line (rust out). I only got three or four pumps and then had to fill the reservoir.
Needless to say I loaded the truck onto my flatbed trailer and hauled it the 20 miles to my mechanic instead of driving it..
I also have had the pleasure of driving on a half brake system one other time, you do not have much braking power at all. Just barely enough brakes to get stopped at low speeds with NO LOAD and not going down hill!
In both cases I had to put the vehicle into NEUTRAL in order to get enough braking power to make a stop (the engine in gear opposes your stopping efforts).. I would not wish that on anyone.
