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Descending steep grades - 808allstarr - 08-14-2017
Anyone have any experience descending 18% grades or steeper with heavy loads on very loose gravel? Maybe any tips on how to? Ive heard that too low of a gear and too slow can cause tires to lock up and start sliding also when jaking tires seem to back peddle if jakes too strong. Any stories or tips on a simalar situation would be greatly appreciated.
RE: Descending steep grades - Hammerhead - 08-14-2017
(08-14-2017 )808allstarr Wrote: Anyone have any experience descending 18% grades or steeper with heavy loads on very loose gravel? Maybe any tips on how to? Ive heard that too low of a gear and too slow can cause tires to lock up and start sliding also when jaking tires seem to back peddle if jakes too strong. Any stories or tips on a simalar situation would be greatly appreciated.
Yee haw, it's called "tobogganing" and it's great fun!
Ok, not really. Yes, I've slid down too many mountains, and will probably end up doing it again...
Tips:
Jakes on medium, not high
Slow, very slow, like crawl. Grades of that pitch on gravel, the gravel rolls under the tires like marbles and You ARE going to pick up more speed than you want to, so use the reliefs to scrub off speed because if you don't, you will get out of control very quickly.
Turns and curves, make them smooth or you're front end will push and there isn't anything you can do about it. Depending on speed, you may have to start them earlier than you think and you'll "drift" outwards in them. Marbles don't just roll straight, they'll go in the direction of least resistance or momentum. This includes backwards!
Tire chains are your friend, no I'm not kidding. I carry tire chains all year round. If you've got an extra set of singles, think about putting them on the steering, again I'm not kidding.
Consider putting a set or two of singles on the trailer tires as drag chains to help assist in braking.
NEVER get out of the truck. You can be parked and the truck will start sliding without notice or warning, so make sure it has a nut behind the wheel at all times. If you exit the cab on a grade like this, it is ONLY because it's out of control and you are bailing for safety.
Do not play with this, $h!t can go sideways in the blink of an eye.
This is where the advise develops too many variables to answer and leads to a few questions that will help give more specific info:
1)How heavy is "heavier"? Everybody has a different threshold for "heavier", and gravity and mass have a correlation.
2)Location? Is this a public road, or in a mine or on a forestry road?
3)OS/OW? Do you have a pilot car to help control traffic if a public road? Might not be a bad idea just for traffic control.
4)Conditions? Is there an alternative? If not, is there equipment that can help you down?
5)Distance of the grade? Are we talking 1/2 mile or several miles? Momentum is cumulative.
Oh, and I won't tell certain stories publicly in print. There are some things that are unwise to put into print and post on the Internet that may be used against you...
RE: Descending steep grades - Brock - 08-14-2017
Cost of running off-road.
Old Chinese proverb: wore out tire better than wore out truck.
RE: Descending steep grades - Brock - 08-14-2017
Make sure your rumning a appropriate tire. If your running highway rubber on crazy grades on gravel then of course your gonna slide. If your on so much gravel that you can keep tires, run the cheap Chinese ones.
There isn't alot you can do, go slow and skid tires or go fast and wear brakes.
RE: Descending steep grades - Magard - 08-14-2017
Slow. Use brakes more. Very little engine brake power. The key is slow and distribute the braking force over all axles. Brakes won't over heat if you go super slow. Steady light continuous brake application to hold speed is what your after.
RE: Descending steep grades - Rawze - 08-14-2017
Something not mentioned that is just as important. Weight distribution. Make sure your wieght is distributed evenly on all axles. too much in the back, it will jack-knife, too much in the front, you will be starring at your tail lights. -- Same thing goes for roads and mountains with snow and ice. I can't tell you how many times that when driving in ice conditions this has saved my bacon because I took the time to scale the load and ensure the weight was distributed evenly on loads that would not normally have to be scale when running in adverse condition.
I would think gravel would be very similar, steep grade or not.
RE: Descending steep grades - the missing link - 08-30-2017
I am going to get my pee-pee slapped for saying this , maybe.
I have ran 5 axel and super bs in the bush and passes in not nice conditions.
When you can't hold it or jake stall , it's a whole new meaning of holy shi#t .
My preference is ( not saying I am right , most probably disagree with me and that ok)
I never have my jakes on high especially with these newer engines
I run on the lower rpm , because if I start to jake stall , or slid I still have rpm to work with and your jakes aren't as strong
I won't use my foot brake while on the jake . The reason is you can only put so much traction or force on a tire before it loses it . So if your jaking and hit the brakes your drives have the most amount of back presser on them .there the first to brake lose ,and the last ones you want to.what I do is use my spike (chicken wing ) for a couple of reasons, it will provide drag on trailer to keep it behind you , and your drives straight especially in corners . Just be very careful you don't overheat the trailer brakes by doing so.also power divider in is a most for me .
Also all the advice here is top notch , not just mine
RE: Descending steep grades - the missing link - 08-30-2017
One other thing I feel must be addressed :
If it takes off because of any reason and you can't hold it , depend how from the bottom . Which isn't very far
you must stop it now
not later , not maybe I can run it out.innocent people die every year because of this . If I can't hold my truck in a bad place ,it is because me not anybody else royal f&cked up.
If that means hurt myself or wreaking my truck so be it . I made the screw up nobody deserves the outcome but me.its way easier to stop a truck at low speeds, every second counts, put in the ditch , it really doesn't matter , stop it . I wil promise that with a mile or two of x amount of grade won't turn out with you walking away at that point.[/size]