Coming down a mountain for first time - Page 2 - Montana Owners Club

beeje · 06-06-2021, 02:39 PM

I have an 18 Duramax Diesel and I do exactly as d q dick stated. Leave the cruise on the exhaust brake on and tow haul on the truck will handle the grades up and down just fine.

Whatever Gets tricky is if you have to break because of traffic in front of you the cruise will go off.

Sheet · 06-06-2021, 02:54 PM

I always use my exhaust brake and keep it in manual shift. Pick a gear low enough and take your time. It will be all good.

Rich Lazz · 06-06-2021, 03:07 PM

my rule ....whatever gear I go up the hill, I go down one lower

bcrvman · 06-06-2021, 03:40 PM

Quote:

Originally Posted by Cindy and Ray's Grand Tour

Hi all, I got myself up to a campground in Groveland, CA near Yosemite on CA120. I did not realize the grade or number of tight turns until I got here. Now I have to get back down without killing us. The grade is about 6% with tight 15MPH curves for about 8 miles. Has anyone else pulled a Monty down this stretch of road or similar drops? Any suggestions for what gear to use on the RAM 3500 or gain to use on the trailer brakes? There are other large 5th wheels and Motorhomes up here so there is no prohibitions on this stretch of road but I don't want to be the first to crash out. Thanks for any info.

On my Ford, I put it in cruise, auto-exhaust brake and put both feet flat on the floor. I use the cruise +- buttons to increase/decrease speed if it is warranted. As a techie computer guy I trust all the computers in the truck to do the job they were designed to. I do the same thing if uphill or downhill, engine never strains and it eats hills at fairly low RPM's. Just don't ask me about fuel consumption, 7 tons pulling 8 tons in a headwind will get you up to 30L/100Km or 7.8mpg real quick. It does better in the mountains if no headwind, the prairies on a windy day are the worst.

Small edit, on the Ford it's Automatic Engine Brake. 2 pushes of the button. It works with cruise. Not sure if tow/haul does much going down, it's for going up but I never turn it off or the AEB when I am towing and generally am using cruise so I may be misinformed as to the tow/haul feature. I do know it does NOT work the same as the old versions of tow/haul.

twindman · 06-06-2021, 04:52 PM

To bcrvman, I think on my Chevy all that tow/haul does is adjust the shift points. Don't know if that is the 'old' or new truck.
Also, I agree about the plains and head winds. I had $2000 of computer boards put in while in Iowa because the regen was happening haphazardly. Start of afterwards on the highway and the computer was re-learning stuff. I think I was only getting about 10mpg on I80 and not much wind. Then got off on I 70 in Kansas and a slight head wind and starting to drop mpg. Finally got to 40 mph winds and I was getting 5 or 6 mpg!!! I thought the computer was really messed up. The next day the winds were mostly gone and back up to 10 or 11 mpg. Then on a stretch from Gallup NM to Holbrook AZ I got something crazy like 14 or 16. When I turned off onto a state highway and a little hilly I was back to 11 or so and has stayed there.

bcrvman · 06-06-2021, 05:02 PM

Quote:

Originally Posted by twindman

To bcrvman, I think on my Chevy all that tow/haul does is adjust the shift points. Don't know if that is the 'old' or new truck.
Also, I agree about the plains and head winds. I had $2000 of computer boards put in while in Iowa because the regen was happening haphazardly. Start of afterwards on the highway and the computer was re-learning stuff. I think I was only getting about 10mpg on I80 and not much wind. Then got off on I 70 in Kansas and a slight head wind and starting to drop mpg. Finally got to 40 mph winds and I was getting 5 or 6 mpg!!! I thought the computer was really messed up. The next day the winds were mostly gone and back up to 10 or 11 mpg. Then on a stretch from Gallup NM to Holbrook AZ I got something crazy like 14 or 16. When I turned off onto a state highway and a little hilly I was back to 11 or so and has stayed there.

Yes, on my 2017 F450 the tow/haul simply adjusts the shift points and it shifts slower, making sure (in uphill direction) it will stay up a gear and not immediately need to downshift again. I do not think it does anything for going downhill, the cruise already handles downshifting and the AEB handles exhaust braking. I have very rarely had to touch the brakes and that was before I was confident that the AEB and intelligent cruise worked.

bcrvman · 06-06-2021, 05:05 PM

Quote:

Originally Posted by bcrvman

Yes, on my 2017 F450 the tow/haul simply adjusts the shift points and it shifts slower, making sure (in uphill direction) it will stay up a gear and not immediately need to downshift again. I do not think it does anything for going downhill, the cruise already handles downshifting and the AEB handles exhaust braking. I have very rarely had to touch the brakes and that was before I was confident that the AEB and intelligent cruise worked.

With regards to regen. On my 2017 F450 I have no dash controls or readouts for that. I have no idea if that is good or bad. I do now have the appropriate OBD connector and software to allow me to reprogram all the missing features on my truck. Maybe regen will show up there when I get around to this job.

dfb · 06-06-2021, 07:23 PM

Could go out the otherwise to 395.. north to Gardnerville. Down to Jackson..

dfb · 06-06-2021, 07:25 PM

Always tow with e brake and tow mode on...

DaveK · 06-06-2021, 08:26 PM

I've towed that road with a gas F-250. Because of low speeds, you'll probably gear lower. I came down in 2nd gear . As some say, go down the same gear you went up. Above all, don't cook your brakes.

I'll admit that I was also surprised.

DaveK · 06-07-2021, 08:48 AM

By the way, I run my trailer brake gain at setting of 10.

TomandMarilyn · 06-07-2021, 08:52 AM

Be very very careful trying manually use your trailer brakes. In my case it caused one of the wheels to lock up just for a couple seconds .. but caused a flat spot on a very expensive tire.

Pace & JoAnn Mimms · 06-07-2021, 09:32 AM

That's great advise - tow haul and exhaust brakes, and very slow - as far as the speed demons behind you - fell free to use my sign on the rear of the 5th wheel - "I MAY BE SLOW, BUT I AM AHEAD OF YOU"!!

Bad Moon · 06-07-2021, 09:08 PM

One of my favorite things about my 2020 Silverado is the 10 speed "Allison". When heading downhill in T/H, it holds your speed on almost any grade. Those rare occasions when the grade is really steep. and it starts picking up speed, I will toggle on the exhaust brake until the speed gets back to where I want it, and then turn it off. My rule of thumb is, if I have to use my brakes, I am probably going too fast.

Livinrdream · 06-07-2021, 11:07 PM

We are in Bryce Cannon, UT. Some of the mountain roads have 8-10% decline. All switchbacks. Our truck is a 2020 F350 diesel with an engine brake. No problems going down or up. We have a 2021 MHC 331RL

Eagleback · 06-08-2021, 11:38 AM

I have a 2017 ram drw. press the exhaust brake button twice until you get a green dash light. start your descent. Then tap the brake peddle once to program the exhaust brake at a certain speed. So if you do not want faster than a 45MPH decent speed, then tap the brake peddle at that speed and the exhaust brake will hold it to that speed. Try it unloaded first then you will get the idea before you go with the trailer.

You may also like: