Originally Posted by cadillackid
I believe air-brakes in a failure situation are much safer.. hydraulic if you lose pressure, pedal just goes to the floor and you have to manually react with emergency brake..
air brakes you get automatic spring brake engagement on brake failure of pressure...
^^^ THIS ^^^
I will never own anything larger than a pickup again with hydraulic brakes.
My first rollback truck was an old Ford F700 with a hydroboost setup. I bought it it put the body on a newer truck, but decided to run it for a little while until I had time to do the body swap.
I had just finished dropping off a 10,000 lb excavator at a demo job, so luckily the truck was empty when it happened, but a rusty brake line burst as I was pulling up to a stop sign at the top of a hill.
It was an old single chamber master cylinder, so I lost all brakes. I had engine braked down to almost stopped, hit the clutch and shifted into neutral, and then was hitting the brakes just to keep from rolling backwards at the stop sign. By the time I realized what had happened, I was traveling too fast backwards to get the transmission in gear. I grabbed the parking brake lever, but it was just that, a parking brake and not an emergency brake. It didn't have enough to even put up a semblance of a fight against the momentum that was quickly amassing.
Luckily there wasn't a car behind me when it happened, so I didn't run over anybody. I changed lanes while rolling backwards so I was at least travelling the correct direction for the lane I was in. It's a good thing I did, because I ended up doing about 35 backwards down that hill and had two cars pass me in the other lane before I rolled to a stop about half a mile later on an uphill slope. Dropped it back into third, drove back down that hill, down-shifted and turned back into the demo job I'd come from. Turned the key off with it in first gear and called my wife to bring me a clean pair of pants.
Air brakes. The only way to go.