best practice descending on steep slope

pawntan · 12-28-2018, 04:53 PM

When driving down a steep slope from Colorado peaks, I've always been advised to use engine brake, and not using the tow vehicle and RV brake to prevent burn out.

However, my thinking is, by not using the RV brake means that the weight of the trailer is pushes down the back of the vehicle at full force.

Coming down from leadville towards Denver, there are many steep down hill and sharp turns at the same time.

My concern is the weight of the RV will push the back of the towing vehicle hard enough causing the rear tire to loose the grip on the road surface.

What is the best practice ?

RogerR · 12-28-2018, 05:12 PM

I personally use my engine to brake in order to have the maximum capacity of my brakes available. Saying this engine braking is probably not the best way going around tight turns. I have never felt that engine braking has harmed my steering ability. But I don't rely 100% on either one.

jimp · 12-28-2018, 05:18 PM

Using the tow/haul mode will help, how much I can't say as I've never done any towing in the big mountains out west. Depending on the vehicle, you can manually select a lower gear which will induce compression braking which will leave your brakes a bit cooler, and keep the tranny in a lower gear which should help with slower speeds. GL

Vasquez Kid · 12-28-2018, 06:44 PM

Pawntan, Give us a bit of info on your rig. Which trailer and tow vehicle do you have? Also which engine and transmission?

I'd love to go explore Colorado!

Grumpy · 12-28-2018, 06:55 PM

Traveled many mountainous roads, used the engine brake and trany as much as possible. Never once had the rear axle break traction. With that said, there will be times you have to apply the brakes too.

Jagiven · 12-28-2018, 07:51 PM

You do not mention what your tv is. If you have a diesel with a true engine break capability, that would be my 1st choice. Depending on the road, speeds, overall conditions, would help decide how to slow down. I have a gas engine, so commonly down shift, and let the tranny help slow me down. Lastly, I make sure the tt brakes are doing most of the work. You absolutely do not want to boil your brake fluid, or you'll lose your tv brakes.

RAurand · 12-28-2018, 08:40 PM

Quote:

Originally Posted by Jagiven

You do not mention what your tv is. If you have a diesel with a true engine break capability, that would be my 1st choice. Depending on the road, speeds, overall conditions, would help decide how to slow down. I have a gas engine, so commonly down shift, and let the tranny help slow me down. Lastly, I make sure the tt brakes are doing most of the work. You absolutely do not want to boil your brake fluid, or you'll lose your tv brakes.

and, watch THOSE RPM's. You don't want to push the RPM,s too high when downshifting the transmission. When I get up to about 4000 RPM's, I start applying breaks.

jbrnigan · 12-28-2018, 09:03 PM

"My concern is the weight of the RV will push the back of the towing vehicle hard enough causing the rear tire to loose the grip on the road surface."

The trailer or 5th wheel is applying "LOTS" of tongue weight to the rear of the truck. The "push" you are concerned about, is being exerted on the rear axle, inhibiting a traction loss. A weight distributing hitch will also aid in truck traction. Also, properly adjusted trailer brakes / brake controller are essential.

nighthawk87 · 12-28-2018, 09:28 PM

Just go slow. Speed is your enemy. Brake and let go then brake again. Drop your speed 10 mph at least then let it build back up and drop it again. NEVER hold the brakes. That heats it up the most. Run in 1st gear.

If that still doesn’t work then you need a bigger truck.

farnik78 · 12-28-2018, 10:07 PM

The key is to keep your speed down. If you get going too fast you have to really use the brakes hard to slow down and can overheat your brakes.If you stay in a lower gear and use the engine brake before you get too fast then you don’t have to jam on the brakes to make the curve at the bottom of the hill. You can just use your brakes lightly.

Bassdogs · 12-29-2018, 08:30 AM

Ditto what several have already said, Keep your Speed down. To add to that, slow down before you begin the downhill run. Think of it like this. add with each push of the gas peddle and minus each mash of the brake. Dropping from 65 to 35 before reaching the drop and there is 30miles per hour your brakes won't have to face on the downhill.

Assuming you are on at least a maintained paved 2 lane, you are probably not going to have any real problem. Look around you and you will see many others doing what you are concerned about. Did I mention that I love the engine brake on my Duramax.

CampNow · 12-29-2018, 10:13 AM

Not sure because the OP hasn't chimed back in yet, but it's possible an unspoken part of the his/her situation may be the trial and tribulation of learning a comfortable braking technique . . . while at the same time feeling pressure to stay with the general flow of traffic. That's tough to do sometimes. For some, it's not easy to ignore 20 cars backed up behind them, and put safety first---especially when they're on a long, narrow 2-lane road with no shoulder.

Also, for others, it's not easy listening to a gas engine pull 4-5k in a low gear while going downhill. Contrary to what some say, it does zero harm to the engine or the tranny---if nothing else, it's certainly a lot easier on the engine and tranny than pulling 4-5k going up a hill.

If one drives regularly in the mountains and wants to ease some of these braking concerns, they may want to consider a diesel (equipped with a good exhaust brake).

brettt · 12-29-2018, 01:22 PM

On steeps grades we set the cruse at 50 mph,and activate the engine brake.The trany may downshift once, but need very little camper brakes!

CampNow · 12-29-2018, 02:46 PM

Quote:

Originally Posted by brettt

On steeps grades we set the cruse at 50 mph,and activate the engine brake.The trany may downshift once, but need very little camper brakes!

Is this a pic of Lake Pleasant, north of Phoenix???

Duke4857 · 12-29-2018, 03:20 PM

I have always used lower gears to keep a safe speed on a downhill. I have always had a gas engine to use for towing. I have towed with 2 Suburbans, one was a half ton the other was a 3/4 ton. I now use a 1500 2015 RAM. The travel trailers were all about the same size 25 foot living space.
The half ton burb was a 4 speed auto transmission I shifted into L2 and used a little brake to keep things slow (1988) The 3/4 ton was a 3 speed auto trans (1990) I also put that into L2 to go down the hill and used a little brake also. The RAM we have now (2014) I set the cruse control for 45 on a two lane 5 or 6% downgrade and use a little brake if I need to slow even more. I guess the computer on the RAM chooses the correct gear to keep the load under control. I feel the transmission shift when needed. The only time I would worry about the back tires loosing traction is in a over speed condition or on icy and packed snow roads. Snowy and icy roads you should be using chains on the tow vehicle and trailer. The best idea on slick roads is to stay off them. Towing on slick roads will make you want to change your underwear when you get parked.

pawntan · 12-29-2018, 03:48 PM

Thank you all for the valuable advice. My setup is Jeep GC V8 with tow/haul button, and Jay Flight 26BH.
Make sense, yes, always keep engine at low gear as baseline, and press the brake as needed, sparingly, to slow down further, if needed.

SkyBound · 12-31-2018, 08:22 AM

Go into the descent with reduced speed. It's easier to maintain a safe speed than it is to slow down to one. Have your transmission set to a lower gear to utilize the engine braking - keep your RPMs moderate but not too high. Use the brake pedal in applications, not riding them. Slow down a bit below your target speed, then release. On any sort of significant hill, I always keep my right hand on the trailer brake control gain. If ever you get into a situation where the tow vehicle begins to lose traction, slide sideways, trailer starts to sway, or tow vehicle brakes are not able to provide adequate braking, apply manual gain. This technique will help slow you down and straighten you out. Again I say, the #1 and best thing to do is start slow and then, using the above techniques, avoid getting into a bad speed/control situation that's more difficult to correct!

RogerR · 12-31-2018, 08:56 AM

SkyBound above wrote he keeps one hand on the brake controller in case he needs it.

I tried that then recruited (asked politely) by wife to put her hand on it and then I give her verbal prompts is I need it. That keeps my hands on the wheel and avoids that nearly automatic look at the controller when I need some help.

**Midnightmoon** · 12-31-2018, 09:09 AM

Stop at the top. I do at any of the steep grades that require the commercial trucks to stop and check brakes before starting down. I've been in the practice from driving commercially over the years and I do the same with an RV trailer. Stop, gear down and then start down slow.

shvanhorn · 01-05-2019, 01:13 PM

From a big rig driving standpoint. Whatever gear it takes to climb the hill, is the one you want to use going down. Allow the rig to accelerate only enough to allow 30 seconds on the brakes to bring your speed back down and no less than 45 seconds for it to increase back up. This timing of using the brakes allows for enough cooling of the brakes, between uses. Never just use the trailer brakes or truck brakes alone. Always use the in coordination with each other. Remember, speed is not you friend on the big hills of I-70, 80, or 90. Senior drivers know the rules I explained earlier and follow it. This also will limit your brake wear considerably. I have driven those roads with my F-250, pulling a Jayco 338RETS and have not seen any increased brake wear, due to it. I also use to drive those roads, multiple times a week and the mechanics were always surprised and the lack of brake wear, they were seeing.

Be safe!! Don't be an I-70 statistic!! Slow and steady will get you up and over the big hill!!

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