I have a 2015 Chev Silverado pickup. We live in the flatlands. We are planning a trip West to the mountains. I have been doing a little reading in the pickup manual. This pickup apparently has features and systems that I did not know about and never paid attention to. I have pulled trailers for years, although not too heavy. I just put the pickup in "drive" and went. In reading the manual, one thing I am confused about and maybe you folks can help, is going downhill. Apparently I have "Hill Descent Control" which can be activated and will help hold you back going downhill. Then I also have "Manual" shift transmission mode where you can downshift to hold you back. However, as I read the hill descent control is deactivated if you are in manual shift mode. So apparently you cannot use them together. So, which would be better to use going downhill?
Going downhill in mountains
- Thread starter gps42
- Start date
The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
xrated
Well-known member
I'm not familiar with the Chevy system, as I have a F350 Dually Diesel. One of the best pieces of advice I can give you, set your speed BEFORE you start the descent. I live close to the Smoky mountain (I know, not as big or high as the ones out west) and I try to abide by the speed limits that are posted for semi trucks. I'm right at 22,000 lbs, truck and trailer, and that is one of if not the most important thing you can do. My truck has an exhaust brake and of course cruise control. I activate the ex. brake and move the cruise control setting to a lower speed. Between the two of them (the truck will downshift if it needs to) I've gone down some pretty long (for our area) and steep roads and never touched the brake pedal. Maybe someone else on here can give you some more info about your particular system in your truck. Have fun and stay safe.
Gizmo
Well-known member
Not familiar with Chevy's options, but it makes sense you cannot use hill descent when in the manual mode as they both are doing the same thing. When you travel in mountainous roads often times on steep grades you will see signs posted "trucks use lower gear". That is what you will do in manual mode, select a lower gear to help control your speed. Sounds like the hill descent does it for you. I would try the hill descent and see how it works for you and use it if does. If however when hill descent is engaged and if you find you are not slowing down to a comfortable speed, then deactivate it and use the manual gear function and select a lower gear. There will likely be some trial and error before you find the sweet spot.
AStravelers
Well-known member
I have a major concern with the Hill Decent Control from what I read in the the 2 links below. Both say the feature uses the vehicle brakes to control the speed! Neither mentions anything about downshifting to use engine braking to keep your speed down.
While that may work just fine with a lightly loaded vehicle. When pulling a trailer and you are running at 60%-100% of your GCVR just using your brakes and not downshifting to use engine braking can lead to brake fading because the brakes get to hot. It is pretty easy with heavy loads and improper driving, to completely loose your braking ability.
https://en.wikipedia.org/wiki/Hill_Descent_Control_system
https://chevroletforum.com/articles/chevy-silverado-hill-descent-control/
In fairness the second link, the video shows the vehicle going down a steep off road incline. Not on a highway going down a mountain with a load.
Bottom line, I would not use the feature on a hwy under load, until I understood exactly how it works. Use the manual transmission shift to control your speed so you don't have to use your brakes more than every 60-90 seconds or more (the longer the better). When you do use your brakes, press them hard for about 10 seconds to bring your speed down 15-20mph.
While that may work just fine with a lightly loaded vehicle. When pulling a trailer and you are running at 60%-100% of your GCVR just using your brakes and not downshifting to use engine braking can lead to brake fading because the brakes get to hot. It is pretty easy with heavy loads and improper driving, to completely loose your braking ability.
https://en.wikipedia.org/wiki/Hill_Descent_Control_system
https://chevroletforum.com/articles/chevy-silverado-hill-descent-control/
In fairness the second link, the video shows the vehicle going down a steep off road incline. Not on a highway going down a mountain with a load.
Bottom line, I would not use the feature on a hwy under load, until I understood exactly how it works. Use the manual transmission shift to control your speed so you don't have to use your brakes more than every 60-90 seconds or more (the longer the better). When you do use your brakes, press them hard for about 10 seconds to bring your speed down 15-20mph.
What drive train? Makes a huge difference.
The D/A system tells you to when speed increases, tap the brakes. The computer will upshift to aid in braking. Gas motor trucks work differently. No matter what, DO NOT ride the brakes. Brake hard to reduce speed. GET OFF the brakes and let it coast until speed increases too much. Repeat as necessary.
The D/A system tells you to when speed increases, tap the brakes. The computer will upshift to aid in braking. Gas motor trucks work differently. No matter what, DO NOT ride the brakes. Brake hard to reduce speed. GET OFF the brakes and let it coast until speed increases too much. Repeat as necessary.
H
Hammster
Guest
Do you have the diesel in your Silverado? If so, use the exhaust brake to help with long descents. We have a 2016 GMC Sierra with the diesel and that exhaust brake is the best thing ever.
The hill descent control is only for very steep, like 10% gradients and for keeping speed around 30mph. Not best to use it.
Use the exhaust brake if you have diesel.
The hill descent control is only for very steep, like 10% gradients and for keeping speed around 30mph. Not best to use it.
Use the exhaust brake if you have diesel.
Larry N.
Well-known member
I believe you mean downshift...
Put your truck in tow/haul mode, leave the transmission in drive. The hill decent feature is for kids crawling around in rock quarries, not for highway use. The brake hard, leave off and repeat is nonsense, you drive in a fashion that minimizes brake use.
AStravelers
Well-known member
lynnmor said:
So what do you recommend when you need to apply the brakes? Press just enough to keep your speed about the same (riding the brakes) or perhaps apply the brakes for a minute or three to slow you down????
Personally I try my hardest to go slow enough and in a low enough gear to only need to apply my brakes every 2-4 minutes. Sometimes coming down a grade for 5-8 miles and only apply the brakes 2-3 times. When I have to brake, I press hard enough to drop my speed 15-20mph in about 10 seconds of braking. If I have to apply my brakes more often than every 60-90 seconds, I am going to fast and in too high a gear, so I slow down and get into a lower gear.
grashley
Well-known member
AStravelers said:
This is the best method. Well stated!
bailer6334
Well-known member
Is your truck gas or diesel? If gas do as others have suggested, pump brakes, down shift. If diesel "Engage Exhaust Brake" a lever on the dash, have in tow haul mode "button on the end of shift column" and when you want to slow down tap the brakes once and the Exhaust Brake will engage, tap brakes again and the Exhaust brake will down shift again.
Hope this helps
Hope this helps
S
SkateBoard
Guest
The Federal Motor Carrier Safety Administration (FMCSA) recommends the same for everyone. Let yourself go about 10mph more then your intended speed then brake until you're 5mph below. Old school called it the stab method. They still teach this today in truck driving school. Keep an eye out for smoke. You have a short time while your brakes work to pull over and let them cool down.
I'm like a few of the others, no GM experience, but in the F-250 I had, the manual feature was fantastic! It essentially was a clutchless 6 speed tranny. It beat the snot of the tow/haul mode. It worked great not only downhill, but uphill as well. I also used the manual feature on flatlands so I could control my shift points. It seemed like that Ford would hold second and third forever in automatic, both with tow/haul and without.
AStravelers describes the best braking method to the tee.
AStravelers describes the best braking method to the tee.
lynnmor said:
You don't"jerk" on the brakes and no one is suggesting breaking the laws of physics. When your speed gets to the point of needing to use the brakes, get on the brakes fairly hard, get your speed down below the speed you want quickly, then get off the brakes and let them cool. If you just keep tapping the brakes, they will just get hot and then fade away. That will happen even quicker if you ride the brakes.
touchracing
Well-known member
I have a 2015 1500 Silverado. GM in there infinite wisdom have two different features with the same name. On Z71 trucks hill decent control is a manually activated feature intended for off roading. The switch will be located lower center dash below the hvac controls. The other hill decent control is activated anytime you are in tow/haul mode and acts as grade braking by down shifting.
AStravelers said:
I call this jerking on the brakes. Why would anyone suggest heating the brakes that much while descending a mountain with a heavy load is beyond me. Again, drive in a fashion that requires a minimum use of the brakes. This old air brake tractor-trailer wives tale is parroted whenever someone asks for intelligent help.
S
SkateBoard
Guest
Follow a large truck down a steep grade and you'll see them doing it. Brake lights will come on maybe every 10 seconds for maybe 3 seconds and they slow down, then speed up and repeat. I'm not sure what they call it now but it use to be referred to as the Stab or Snub method.
Check out this video. Brakes on non stop.
https://www.youtube.com/watch?v=EWcqNTVo8RY
Check out this video. Brakes on non stop.
https://www.youtube.com/watch?v=EWcqNTVo8RY
