quote:

Originally posted by slosig:

quote:

Originally posted by sigcrazy7:
Bentonite is just bentonite. No such thing as “gravel.” There’s a large plant in Lovell, WY where it is mined and packaged. That’s probably 75% of the heavy stuff over that mountain

That’s what I thought as I’ve only seen it as powder or drilling mud, which looks a lot like liquified clay, and sure cracks up like clay when dumped on the ground and allowed to dry out.

Makes sense it would be involved in a lot of the problems if it is that high a percentage of the heavy cargo.

Thanks!

Bentonite IS a form of clay. It has expansive qualities that make it useful for fracking and for sealing earthen “tanks” or ponds.

You can only gear down if you can get the truck slow enough first. Depending on your skill, you can shift while only gaining 100 rpm (the truck drifts faster while you're shifting). Your red line is 2100 rpm. A full gear is 500 rpm. Therefore, you have to get the truck down to 1500 rpm before double-clutching into the lower gear, if you are good. If you suck, you'd better be at 1400 to give yourself a margin of error. The strength of your engine brakes are totally dependent on engine rpm. Therefore, while they may be really strong at 1900-2000 rpm, they do very little at 1500 rpm. You must use friction braking to get that last 250 rpm to go from 1700rpm down to 1450 or so.

IOW, if you have no friction brakes left, you aren't going to use engine brakes to get to a lower gear if you are really heavy. Engine brakes allow you to hold the gear, but the brake pedal is needed to initially get you to that lower gear.

This is where the type of transmission has a lot to do with it. If you have a nine or ten speed, you have a full-gear ratio transmission. You have 500 rpm between gears. These are a pain because it is harder for you to find the best gear on uphill pulls, and it leaves you a bigger challenge when downshifting, as I've already explained.

If you have something like a thirteen, fifteen, or eighteen speed, then you have more options. A thirteen speed is basically a nine speed transmission with a splitter for the top four gears. Instead of having 500 rpm between gears, you have 250, so you can split down the gears. Say you're on a downgrade and need to go lower, you can make the downshift at 1700 rpm where your engine brakes are strong, instead of 1500 where you must use the friction brakes. I don't know if this makes sense. You sort of have to do it to really understand it. Like when my brother tries to explain to me the mechanics of crabbing an Airbus, and how he instinctively pushes the rudder as needed. It would make more sense if I were a pilot.

If you are wondering why all trucks don't use 13, 15, or 18 speed transmissions, it is because they are less efficient. You are essentially running the power through two gearboxes. Company trucks like Swift, England, and Knight run ten speeds. Owner ops prefer the split ratio boxes. Within ten years, most trucks will be automatics anyway. It's easier to hire unskilled wheel-holders with automatics.

quote:

Originally posted by sigcrazy7:
If you are wondering why all trucks don't use 13, 15, or 18 speed transmissions, it is because they are less efficient. You are essentially running the power through two gearboxes. Company trucks like Swift, England, and Knight run ten speeds. Owner ops prefer the split ratio boxes. Within ten years, most trucks will be automatics anyway. It's easier to hire unskilled wheel-holders with automatics.

sigcrazy7, Thank you for the very clear and detailed description. I wasn’t thinking that the redline was that low, but now that I think about it, if the redline on the DT466 in our ranch truck is higher isn’t much higher. Is the maintenance about the same on the “split gear” gearboxes? And on the automatics, are they going to be less safe on a hill (more prone to fools having problems) or will they do okay?

quote:

Originally posted by slosig:

quote:

Originally posted by sigcrazy7:
If you are wondering why all trucks don't use 13, 15, or 18 speed transmissions, it is because they are less efficient. You are essentially running the power through two gearboxes. Company trucks like Swift, England, and Knight run ten speeds. Owner ops prefer the split ratio boxes. Within ten years, most trucks will be automatics anyway. It's easier to hire unskilled wheel-holders with automatics.

sigcrazy7, Thank you for the very clear and detailed description. I wasn’t thinking that the redline was that low, but now that I think about it, if the redline on the DT466 in our ranch truck is higher isn’t much higher. Is the maintenance about the same on the “split gear” gearboxes? And on the automatics, are they going to be less safe on a hill (more prone to fools having problems) or will they do okay?

Maintenance on transmissions is the same for all manuals. Change the oil with a synthetic 50wt every 500,000 miles. I don't know how the automatics are for safety or maintenance. I do know that computer controls won't overcome the laws of physics. If the driver gets the truck beyond the computer's ability to manage the speed, then it will runaway too. The computer will have to upshift every time the truck hits redline, just as a driver would. If the engine explodes (your valve train would be the first to go. That's your engine brakes!), you've got nothing. At lease in the next higher gear you've got something in the way of holdback, so I'm sure the computer would have to keep shifting up as speed increases.

Another note: If you are in a semi and running away, lock your fan on. A semi's fan at 2100rpm draws 30hp. It can actually make a big difference. Sometimes the truck won't hold the gear I want, and locking the fan on makes the difference to hold that gear. Every little bit helps.

quote:

Originally posted by sigcrazy7:
You can only gear down if you can get the truck slow enough first. Depending on your skill, you can shift while only gaining 100 rpm (the truck drifts faster while you're shifting). Your red line is 2100 rpm. A full gear is 500 rpm. Therefore, you have to get the truck down to 1500 rpm before double-clutching into the lower gear, if you are good. If you suck, you'd better be at 1400 to give yourself a margin of error. The strength of your engine brakes are totally dependent on engine rpm. Therefore, while they may be really strong at 1900-2000 rpm, they do very little at 1500 rpm. You must use friction braking to get that last 250 rpm to go from 1700rpm down to 1450 or so.

IOW, if you have no friction brakes left, you aren't going to use engine brakes to get to a lower gear if you are really heavy. Engine brakes allow you to hold the gear, but the brake pedal is needed to initially get you to that lower gear.

This is where the type of transmission has a lot to do with it. If you have a nine or ten speed, you have a full-gear ratio transmission. You have 500 rpm between gears. These are a pain because it is harder for you to find the best gear on uphill pulls, and it leaves you a bigger challenge when downshifting, as I've already explained.

If you have something like a thirteen, fifteen, or eighteen speed, then you have more options. A thirteen speed is basically a nine speed transmission with a splitter for the top four gears. Instead of having 500 rpm between gears, you have 250, so you can split down the gears. Say you're on a downgrade and need to go lower, you can make the downshift at 1700 rpm where your engine brakes are strong, instead of 1500 where you must use the friction brakes. I don't know if this makes sense. You sort of have to do it to really understand it. Like when my brother tries to explain to me the mechanics of crabbing an Airbus, and how he instinctively pushes the rudder as needed. It would make more sense if I were a pilot.

If you are wondering why all trucks don't use 13, 15, or 18 speed transmissions, it is because they are less efficient. You are essentially running the power through two gearboxes. Company trucks like Swift, England, and Knight run ten speeds. Owner ops prefer the split ratio boxes. Within ten years, most trucks will be automatics anyway. It's easier to hire unskilled wheel-holders with automatics.

Aha! It does make sense...but only because you explained it so well. I feel like one of the missing pieces of the puzzle suddenly popped into view with your explanation of the transmission, redline, and RPM drops. Like slosig, I thought these big rigs had slightly higher Redlines and I didn't realize that the RPM drops were that high.

I have a better understanding of the dynamics involved now...not that I could drive a runaway big rig down a grade...but at least I can understand what's involved.

Oh, and I used to do a little flying years ago so I even understand a bit about flying sideways...not to mention the fact that my brother flies an Airbus also.

Thanks again for taking the time to lay out your explanation so well.

Great explanations sigcrazy7! Driving one of those big rigs sounds almost as complicated as flying complex aircraft - and the disturbing thing is the level of training and experience some of those truckers might have with a moving 40 ton piece of kit. The old saying: "There are old pilots, and there are bold pilots. There are no old, bold pilots."

[QUOTE]Originally posted by Gustofer:
I don't know about anyone else, but if that were me in an out of control rig, I'd have made an attempt to dodge any traffic and when that failed, hit the ditch. No sense taking anyone else with you...unless you want to that is (not making any assumptions here.)



Here is an oldie but moldie. But as I recall, it was a real popular song back when.
Your comment about sacrificing yourself to save other innocents brought it to mind..

https://www.youtube.com/watch?v=2EAZlArfDOw

Local radio news is reporting that in the driver's weekend court appearance he is claiming that his brakes failed and that he drove on the right shoulder for a distance until he came up on another tractor trailer rig stopped on the shoulder and then he swerved back into the right lane. He said his speedometer indicated 85 mph and that just before impact he closed his eyes, expecting to die.

His attorney said that he has since instructed his client to not say anything further "so as to not taint the ongoing investigation".

There was some conflicting news also as the report first stated 'that he had been cited previously for not understanding English well enough' but later the news report stated 'that he had never been cited.' local radio news has changed their statement and stated that the company had been previously cited for drivers not understanding English well enough.

The company he drove for operated 5 trucks and the company had 30 violations since 2017, ten of which were brake related violations.

This message has been edited. Last edited by: Modern Day Savage,

quote:

Originally posted by sigcrazy7:
< snip >
He should have rubbed off half the truck on every guard rail he could find. Laid it up on the side. Run it up a bank. Something besides what he did. He probably figured he could ride it out.

If you loose the brakes in a vehicle you are driving wreck the damned thing if need be. Doing so beats wrecking the vehicle you are in plus others.

That was taught in my behind-the-wheel driver's education course in high school.

He'll claim he didn't see the turn-out or was so task saturated driving that he didn't realize what it was until he was past it.

There are so many very professional , talented truckers out there running hundreds of thousands, even millions of miles without issues.

Sadly this guy probably wasn't one of them.

Once had a guy coming down a long, steep grade at 103 mph in NEUTRAL. We passed and my radar caused his detector to beep. I had to go a mile futher to hit a cut across to pursue him.

He hit the brakes and 2 miles later by the bottom of the hill one of the rears (IIRC?) was on FIRE. I saw smoke and smelled brakes a mile before I saw the truck!

I didn't park behind him, went to the front, afraid a tire may blow from the heat of the brakes. They were just cooked.

This guy was a new driver, LATE to deliver and felt he could make up time. He was at 80K weight.

Bozeman Hill on I-/90 regularly saw 80-90+ mph speeders, letting it run down the long grade. Thankfully only the occasional disastrous crash.

850 KOA news radio had an interesting news report this morning. . Correction: 850 KOA replayed a portion of a CBS 4 report.

CBS 4 sent one of their reporters on a ride-along with the director of the U.S. Truck Driving School and they followed a portion of the same route that the driver of the runaway truck followed. He demonstrated the correct way to drive this downgrade and the various road signs that the driver should have been following, pointing out the runway truck ramp with sand at the end that the driver should have taken.

At one point the academy driver made a statement that even after the runaway truck driver missed the ramp he still had opportunities to stop the vehicle and said something along the lines of "he could have started to shut the truck down".

Also, according to the 850 KOA news report, charges have yet to be filed against the driver, as the DA is investigating whether negligence can be proven which is what is necessary for a Vehicular Manslaughter charge. Normally reserved for drunk driving charges, investigators are checking to see whether they can prove that the driver failed to inspect his truck.

[Video and pics at the linked report]

Truck Driving School Director On Semi Flying Down I-70: ‘Should Have Exited’

April 29, 2019
WHEAT RIDGE, Colo. (CBS4) – Questions about how a semi-truck driver could lose control of their vehicle after a man, originally from Cuba, caused a 28 vehicle crash. Witnesses reported seeing Rogel Aguilera-Mederos speeding down Interstate 70 before the wreck.

Aguilera-Mederos told investigators the truck’s brakes failed.

If anyone knows how to drive an 18 wheeler, it’s Harold Trent. He is director of the United States Truck Driving School in Wheat Ridge.

He took CBS4’s Rick Sallinger on Lookout Mountain to show how the stretch of Interstate 70 is supposed to be driven. First, he said those not familiar with it should take extra caution by checking the adjustment on their brakes.

The numerous yellow signs warn steep grade and sharp curves ahead.

“Meaning be in a gear low enough that will keep you in control,” Trent said.

He noted low gear will make it less necessary to use brakes. On the ride, there were uphill stretches and a runaway truck ramp where the runaway driver could have slowed.

The suspect truck barreled on past it, instead moving to the left and forcing a pick up off the road.

“He should have exited right here and followed that runaway truck ramp,” Trent said while driving past it.

By now, the chance to move into a lower gear appears to have passed.

“It’s near to impossible for a driver to make a downshift at that rate of speed,” said Trent.

He pointed out how truck brakes get hot when repeatedly stepped on, making the gap between the drum and shoe too great.

“It’s too big it can’t make contact with the brake drum any longer,” he said.

But even after passing the runaway truck ramp, filled with sand, gravel and barrels at the end, there were other opportunities to stop. There were empty spots along the right side of the highway.

“Could have pulled off here?” Sallinger asked.

“Yes, he could have absolutely pulled the truck off here,” he answered. But Trent acknowledged it was very likely the flatbed carrying a load of lumber could have flipped over.

Instead the truck continued to Denver West. Four people died in the crash.

This message has been edited. Last edited by: Modern Day Savage,

Here's a ride along of the route with some decent narration. The escape ramp is at the 11:30 mark. The narrator and comments make a big deal out of the fact that the driver didn't speak english and couldn't read the escape ramp signs. No excuse. You don't need a sign to tell you that a sand trap and impact barrels are your best option for a run-away.

I still think it was a poorly maintained truck, with a driver who didn't want the expense of a wrecker pull from the sand trap, and tried to ride it to the flats. Look at all the uphill climbs prior to the final hill.

quote:

Originally posted by sigcrazy7:
Here's a ride along of the route with some decent narration.

The driver makes some great points for anyone who drives the interstates. I'll sure be more left-lane proactive on my next road trip.

I'm bumping this old thread with an update as the driver was found guilty and has received a harsh sentence.

[Note: hyperlinks found at linked website article.]

=========================

Man convicted in deadly I-70 truck crash gets 110 years

By: Robert GarrisonPosted at 4:10 PM, Dec 13, 2021 and last updated 10:32 AM, Dec 15, 2021


Photo by: KMGH

DENVER — The semi-truck driver convicted on several charges in connection with the April 2019 crash on Interstate 70 that killed four people was sentenced in a Jefferson County courtroom Monday.

Rogel Aguilera-Mederos was sentenced to 110 years in prison. Judge A. Bruce Jones said his hands were tied when it came to sentencing because of mandatory minimum laws in the state. He sentenced Aguilera-Mederos to the minimum in the range available to him on all counts, which must be served consecutively.

On Oct. 15, a jury convicted Aguilera-Mederos, 26, on 42 counts, including vehicular homicide, first-degree assault, attempted first-degree assault, reckless driving and careless driving. He was also convicted on multiple counts of careless driving, reckless driving, and vehicular assault, though the jury found he was not guilty on several counts of attempted first-degree assault.

On April 25, 2019, he was driving a semi-truck carrying lumber on eastbound I-70 down from the mountains into Lakewood. He told police he had lost control of his brakes, and when he encountered traffic that was stopped because of another crash on I-70, he drove on the shoulder before crashing into traffic at the Colorado Mills Parkway overpass.

Twenty-eight vehicles, including four semi-trucks, were damaged or caught on fire in the wake of the fiery crash. Investigators estimated he was going at least 85 miles an hour just before the crash.

Four people died in the crash from different vehicles and at least six others were injured, and the eastbound lanes of I-70 were closed in the area for more than a day.

All four victims were Coloradans:

• Doyle Harrison, 61, of Hudson

• William Bailey, 67, of Arvada

• Miguel Angel Lamas Arrellano, 24, of Denver

• Stanley Politano, 69, of Arvada

Aguilera-Mederos was working for a Houston-based trucking company at the time.

During the trial, prosecutors argued that Aguilera-Mederos could have taken steps to prevent the deadly crash, including using a runaway truck ramp miles before the crash, and that he “made a bunch of bad decisions” instead. His defense attorneys claimed he did not know the truck’s brakes were smoking or that he would not be able to stop his truck, though others testified at the trial that they had seen them smoking.

Before Judge Jones handed down his sentence, family and friends of Aguilera-Mederos spoke in support of the 26-year-old. His attorney argued that his actions were a series of negligent decisions, and he was overwhelmed with the situation. He contended that the judge was not bound by the mandatory-minimum sentences laws, citing previous court cases, and urged the judge to consider a lighter sentence. However, the judge did not agree.

Aguilera-Mederos also took to the podium in a tearful plea for leniency.

"I'm dying. It is hard to live with this trauma. I can't sleep. I'm thinking all [the time] about the victims. This was a terrible accident, I know. I take responsibility. But it was not intentional. I am not a criminal," Aguilera-Mederos said.

The judge also heard from the victims and family members of the victims, some through victim-impact statements read by the prosecution. Many of them said Aguilera-Mederos should have used the runaway truck ramp or veered off and away from the line of cars he crashed into.

Restitution will be determined at a later time.

110 years.

How many drunks that committed homicide have been sentenced to far less? Repeat offenders, even.

Sorry, but I don't think 110 years fits the crime here.

^^^^
I had the same thought when I heard the sentence announced.

I'm a tough on crime supporter, and there is no doubt that this man is guilty and was negligent and serious punishment is called for.. but when I think of other incidents involving death and destruction that were committed willfully and intentionally that resulted in either lighter sentences or probation, and considering the examples you give, it seems this man's sentence is excessive.

We had another recent sentence in which a BLM activist shot a motorist in the back of the head, the man survived but with serious permanent impairment. The shooter is a defense attorney and received a plea deal in which all charges related to the shooting were dropped, and instead agreed to plead guilty to tampering with a dead body, and received an 11 year sentence that will likely be reduced by half.

I believe there is a real disparity in how similar crimes are treated in various parts of this country.

I think the widespread media coverage of the crash fanned the flames of public outrage, although apparently sentencing minimums played a part as well.

There is a petition being circulated calling for this truck driver's sentence to be reduced.

quote:

Originally posted by fwbulldog:
110 years.

How many drunks that committed homicide have been sentenced to far less?

Vehicular manslaughter which the drunk did not remember or a kid which could have dumped his truck over a guard rail but chose to use occupied vehicles as his crash barrier?

110 years. That's quite a sentence. I'm sorry but that doesn't sound like a just, reasonable punishment. Wow.

That's only 27 and a half years per needless death.

I find the sentence very lenient.

110 years for negligence? Wow. If this guy is such a danger to society that he must be locked up for 30 years longer than a human lifespan, wouldn't it be more reasonable to execute him?

This guy panics under pressure and makes a series of errors and that's worse than a gang banger killing multiple people or a pedophile raping a child?

I haven't read the whole thread, can someone explain what he did that was so heinous, evil, wicked, and depraved that it warrants this kind of sentence?