Well, I got lucky

I found out that this off road dump trucks parking brake doesn't hold on a hill today.

I had the dump truck unchained and was on the hood folding the mirrors back out when the f@#&$* started rolling. I barely made it into the cab and got the truck stopped with the service brake. I was two feet away from hitting my tractor, and more importantly, anything could have happened up there with it moving, I got lucky. I didn't fall when it came down the ramps, didn't get hurt, and nothing was broken.

Anyone have something similar happen to them?

Glad you made it out thats a long scramble up to cab too

Jonas302 said:

Glad you made it out thats a long scramble up to cab too

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I was on the hood of the truck when it happened, so I was along for the ride. It was in my best interest to make it to the cab.

I don't think I would have risked it if I were on the ground. None of the things we do out here are worth life or limb.

Scary....I think I would always assume they are broken from now on. They make new truck chassis's everyday, but people are hard to replace.

I'm wondering if there shouldn't have been something in the truck or some kind of notice that it was unsafe to operate. I don't believe that a parking brake problem would have just happened to you this time only. The parking brake is spring applied and hydraulic released. As I recall those machines have two park brake settings. One locks up all the service brakes but not the parking brake while the other sets just the parking brake. With just the service brakes applied and the engine shut down I have seen other makes lose that pressure and the trucks roll away. Had a D550 Cat artic do that and it headed for a settling pond. It ran out of air and locked the parking brake just before the truck would have taken a swim.

Things like that get your blood flowing, opens up any clots that you might have.
I was loading a John Deere 450 crawler loader on a tilt bed trailer. Parked on a gradual hill, as the trailer tilted down the truck started down the hill. It was shut off in gear, so was not going fast but chugging away picking up speed. I got the bucket down and parking brake latched on the crawler and jumped off trailer made it into the cab in time to push the brake pedal before it ran into the ditch. Had a wedge shaped railroad tie that was used from then on.

Had a guy change a pilot control valve on a hoe. Another guy took it out and marked it backwards. Poor fella installed the new one off the last guy's marks. He started it up and it started swinging by itself. Almost took me and 2 others out before he got it shut down.

That sounds way more excitement than I want out of a single day.

John C. said:

I'm wondering if there shouldn't have been something in the truck or some kind of notice that it was unsafe to operate. I don't believe that a parking brake problem would have just happened to you this time only. The parking brake is spring applied and hydraulic released. As I recall those machines have two park brake settings. One locks up all the service brakes but not the parking brake while the other sets just the parking brake. With just the service brakes applied and the engine shut down I have seen other makes lose that pressure and the trucks roll away. Had a D550 Cat artic do that and it headed for a settling pond. It ran out of air and locked the parking brake just before the truck would have taken a swim.

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The messed up thing is that I also had the service brake lever set when it was on the trailer, and it was in the engaged position as it was rolling down the hill. So I had both the parking brake and service brake set...
Would it be possible for the service brake to bleed off while bebop-ing on my trailer down the road? It is an old rock truck.

WRA said:

The messed up thing is that I also had the service brake lever set when it was on the trailer, and it was in the engaged position as it was rolling down the hill. So I had both the parking brake and service brake set...
Would it be possible for the service brake to bleed off while bebop-ing on my trailer down the road? It is an old rock truck.

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likely does`nt have any stopping power at all anytime

I remember years and years ago a guy parked a hay hauler Freightliner on a slight incline near and pointing towards a cafe. People were dropping their fork fulls of two over easy with B&G
racing to get out of Mabel's Cafe as that cab over fruit-can made a new entrance for customers. Didn't set brakes.

Back in the eighties I had a Brockway 360 tractor and Hyster lowbed and I was hung up on a hump in the road. I was in a hurry and did not put-on the parking brake when leaving the cab. As soon as I started to put the cylinder down to lift the deck the unit started to move real fast. For a second I did not know what to do get to the tractor or let the deck back down. Thank God I picked up the cylinder and got the trailer hung up enough to get the brake on. Did not know I could move that fast.

Flat Thunder Channel said:

Scary....I think I would always assume they are broken from now on. They make new truck chassis's everyday, but people are hard to replace.

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I don’t know about that ,I’ve had a lot of bosses tell me “I can replace you in a heartbeat “.

Truck Shop said:

I remember years and years ago a guy parked a hay hauler Freightliner on a slight incline near and pointing towards a cafe. People were dropping their fork fulls of two over easy with B&G
racing to get out of Mabel's Cafe as that cab over fruit-can made a new entrance for customers. Didn't set brakes.

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At Carls Eburg? That Mabel? I loved her!

WRA said:

The messed up thing is that I also had the service brake lever set when it was on the trailer, and it was in the engaged position as it was rolling down the hill. So I had both the parking brake and service brake set...
Would it be possible for the service brake to bleed off while bebop-ing on my trailer down the road? It is an old rock truck.

Click to expand...

When I was a kid and doing one of my first moves I did that in reverse and went off the back of the trailer. I went to pick up a TS 24. Got it started had air made a quick uball to line up with the trailer.
Drove up to the nose and she didn't want to hop up. I looked over at the Cat hand and he made a running motion, like get a little run at it. At the time missing from my knowledge of cans was the fact that
just expect it does not have brakes. That would have been a good thing to know as I got my run at it got the tractor up and stabbed the break pedal... and as C W McCall said "it was kind like stepping on a plum'"
The tractor bounced up on top of the axles and right off the end of the trailer and we stopped in a hurry when cutting edge/apron hit the step... I looked at the Cat hand who at this point had came to a stop and
was laughing so hard he was crying. After everybody had got a good laugh at the dumb girl and the flying 24, he gathered himself together enough through continuing gales of laughter to shove me and the tractor back
up on the trailer! In a quarry I used to frequent there was a a little sign on the roof of the office. It said "Stay alert, we need live alerts." Glad you were OK!