Can a load shift wreck you?

The next to last company I drove for had a driver killed because the load shifted while the driver was on the on ramp. He may have been going too fast, but the ultimate cause was the loaders loaded the truck wrong, and left an almost three foot gap between the product loaded against each wall.

 

This will date me but here goes. I was on a trip to Novato, CA from Washington state back in the 60's. Had just taken the southbound I-505 cutoff from I-5 to I-80 near Sacramento. Back in those days it was a two lane road. I was traveling on a long straight stretch of that road following a semi with a box trailer when all of a sudden the trailer just rolled off the truck and down the ditch on the right side of the road. The tractor just kept driving down the road and came to a stop on a small bridge several hundred yards from where the trailer ended up. I've always wondered why the trailer came off the truck. Obviously, the trailer wasn't properly connected, but how did it get so far down the road before it came off? We were at least 10-15 miles from any town.

 

Well, not only a top heavy load shifting or any load shifting for that matter or cross wind's but I've noticed all the lazy driver's these day's who NEVER do their PTI (Pre trip inspection) like they are supposed to which could lead to a number of thing's. under inflated tire hitting a hard bump or from swaying could cause a tire bead to break loose from a rim and shift a load. Load not centered and/or secured. Suspention failure weather it but a cracked leaf sping of overly worn air bag. Fatiged or over loaded U bolt's, saddle's, tandem main frame mounting bolt's sheering or snapping. And one that I have been stuck with before personally, someone abusing the #### tandem slider system because they didn't know what they were doing so the rail's were bent to hell and some of the weld's broke free of the cross member's leaving enough room for the tandem slider box to twist about freely causing the trailer to dog track like a MFer. There's all kind's of thing's that can go wrong to cause a truck to tip over out of the blue.

As for an under inflated tire bead breaking loose from the rim, it's like blowing one out. If the load is top heavy enough and is heavy like a beer load, the other tire could be an older more worn tire than can't handle the load and it blow's creating a chain reaction then the next thing you know the truck is sitting on it's side. Most case's I've seen though are due to driver error weather it be the way they are driving or the lack of excuse to get off their lazy ### and do their PTI like they are supposed to instead of jumping behind the wheel, coloring in their log book and hauling ### with no thought of their or anyone else's safety.

If this guy was driving like he is supposed to and wasn't doing anything wrong then it sound's to me like it was a suspention failure leaf spring or air bag depending on what type of trailer it was. It's actually happened to my CDL instructor where an air bag blew and #### near rolled the truck. He got really lucky to keep it up right.

 

Well, several thing's could have happened in that situation. One, the driver failed couple the truck and trailer properly where the jaw locked around the wrong part of the kingpin causing a false lock, the locking jaw in the fifth wheel failed do to a crack or fatigue which can be caused by failure of preventive maintanence from worn part's, or slamming into the kinpin way to #### hard, or the lock the hold's the jaw closed was out of ajustment which can start to be noticed by the slack from the trailer sliding forward or back when the tractor first take's off or the tractor is at full stop and you feel it shove. If I remember correctly, Holland is the only company that I am aware of that offer's a double jaw fifth wheel that does not need to be adjusted and never gain's any of the so called "slack".

But never, ever have I seen or heard of a kingpin breaking or snapping off the skid plate underneath a trailer. I have seen a fifth wheel and the mounting braket still coupled to a trailer where all the frame mounting bolt's have been sheered and fifth wheel jaw's broke but never a kingpin.

But from what you say here, this just sound's like driver error like it is in most case's where they have failed to climb under the truck with a flash light and check to make sure the jaw is properly secured around the kingpin and the lock and plunger are visible behind the jaw. It's amazing how many idiot's they will hire just to have an ### in the seat these day's.

 

man it depends on the ramp. Theres a ramp near my house thats marked 55, never taken it in a truck but it looks like thats a good speed for a truck on that ramp. I take it at 75 in my car no problem....theres also one in a nearby town, posted 15 which is the maximum i take it in my car. in the truck i take it at FIVE! (Westnedge Avenue South in kalamazoo, MI, exit 76A on 94...i think)

Then theres the ones that actually show a truck on the sign, thats obvious...


Anyway, to the OP. the load probably didnt shift if it was on a straight road. Loads usually dont shift on straight roads. Unless it was within a mile or so of a curve or ramp. its very easy to get tired and end up off the road, and if you touch the dirt doing the speed limit, in some places its soft enough that the truck will sick in and trip over itself and fall over. It looks really funny when it happens, like the truck just fell over.

Man, you've never had a near-jackknife, have you? The trailer tires do not have to be locked up to jack knife. Infact, they dont have to lose traction either. A jack knife can be caused by losing traction on any axle. In particular, i almost jack knifed on the 402 once when i hit a 50 km long patch of black ice. I didnt even touch the brakes, but if i would have touched them, i would have put it in the ditch. I came up to an area where the traffic was moving slowly and there were a lot of vehicles in the ditches. I knew what was going on. I got over in the left lane to pass everyone and coast myself down to a safe speed without touching my brakes. The truck got a little bit squirrely, the tractor and trailer both lost traction and were coming towards eachother, but i saved it and the maneuver worked as intended.


Another time, and this was at about 3mph, i was at a beer warehouse early in the morning, the parking lot was covered with ice. it was a big yard so i pulled past the docks and turned to set myself up for a mostly straight back. Man, all of a sudden the trailer came at me. I had to aggressively counter steer to avoid it.

 

A quick jerk of the wheel can set the cargo in motion as someone does a quick dodge to avoid a car or deer, etc. A good driver knows his load as well as a good shipper knows how to load it. A sealed trailer is a mystery. A good driver knows not to jerk the wheel but to read traffic far in advance if possible. Them yellow signs are a good caution and great for new drivers. I seen ones that were over rated and probably were made from a lying driver that wrecked, lol.
Newer trucks such as my 2009 Pete have Electronic Stability Control. The truck will sense a roll over and lock down the brakes automatically on the corresponding side to slow the truck and counter the rollover. One of our drivers told me a story as he tested it out. He hit a ramp faster than normal and the brakes kicked in and about put him into the windshield. I asked him, "What if the fuse was blowed or something you dummy"? I once was driving through the mountains on some back road. It had some very short quick mild turns like a little left, little right. Nothing that you would think would cause a rollover. I felt a small short jerk of the brakes as the system kicked in. I slowed down a little then.

Proziac, I was headed into Indy last winter on I-74. It was well below freezing and the road was still in decent shape but not salted yet. As soon as I crossed an overpass, I hit black ice and eased off the gas with no brakes. The weight of the trailer started to try and push me in to a jacknife not on the trailer but on the truck end. I immediately gassed a little to counter the trailer pushing on me and all was well. The next two overpasses were the same way until I got to I465 and the loop was treated. Long story short the trailer doesn't have to come around to jack knife. The tractor can lose traction.