Towing down a steep grade without burning up the brakes

[PSU1981]

I have a 2015 Tundra pulling a 2015 27FB FC & we are considering making a trip through the Rockies. I have never pulled up & down a big incline/decline yet. How do I best tackle this with auto transmission gears + brakes so I don't end up in one of those run away ramps?

Thanks,

Glenn
Spring, Tx

[SpletKay06]

Just Slow down use tow haul mode and down shift as needed to keep your rpms up. Dont be afraid to go slow amd dont ride the brakes.

[Moflash]

As mentioned above travel at a comfortable and safe speed.Use the transmission as your brake down shifting to reduce speed.Stay in the slow lane.Your engine will make some noise but do not panic as long as you do not go into the redline on your tach you will be fine.Keep a eye on the traffic behind you as Semi's have been known to loose their brakes on steep grades.50-55mph should be your target speed in most cases.Use just your trailer brakes if needed by squeezing the two levers together on your brake controller a brief couple of intermittent light squeezes will slow you down on steep grades.Just keep calm and you will do fine.

[wulfraat]

I live here in Colorado - pull through the mountains all the time - just came through Eisenhower tunnel to Denver a couple days ago - 12 miles or so total at 5-6% downhill grade... no big deal.

Just use 2nd & 3rd gear to keep your speed under 60mph on the straight aways and under 50/45 or less if the road / highway curves a bunch. Brake intermittently when needed. On long relatively straight stretches I like to brake firmly to take 5-10pmh off my speed... then use the gears... slowly coast back up to speed... then brake again, etc..

You'll be fine enjoy the views of beautiful CO!

[Rocinante]

Everything folks have said before about down-shifting (even with an automatic transmission) is right on target. However, I'd add that the right time to start downshifting and getting ready for the fun is when you see that first hill warning sign that says something like "7% grade ahead."

Honestly, our most hair-raising experience so far (including crossing the Rockies) was in California, on Route 62 heading downhill from Yucca Valley to I-10. We didn't downshift quite as soon as we should have, so it got more exciting than we wanted it to be. No bad outcome or anything, just a little scary until we got downshifted and were running at a more comfortable speed. As long as you downshift early and let the transmission do it's work for you, you won't need the brakes too much. Keep those brakes nice & cool so they are ready for you if you need them.

So, don't let it get away from you. If the curve speed limit warning sign says "35MPH," we slow down to 35 MPH, no question about it. We'd rather be going too sloooow, feeling like Jed Clampett driving his truck in Beverly Hills, than like Speed Racer blasting down the mountain and looking for a gravel truck ramp to save us from ourselves.

[AnnArborBob]

All the advice given here is good. My best advice is not to let the speed get away from you in the first place. It's not always easy to slow down from 65 to 55 or even less unless you have a big diesel truck with an engine brake so just keep it as slow as you feel is comfortable from the very beginning. Do not expect to be able to slow down from your initial speed by very much (so pick a conservative speed at the beginning of the hill) and you will be fine. Remember, thousands of other RV's have already made it down that hill!

[Foiled Again]

Originally Posted by AnnArborBob

All the advice given here is good. My best advice is not to let the speed get away from you in the first place. It's not always easy to slow down from 65 to 55 or even less unless you have a big diesel truck with an engine brake so just keep it as slow as you feel is comfortable from the very beginning. Do not expect to be able to slow down from your initial speed by very much (so pick a conservative speed at the beginning of the hill) and you will be fine. Remember, thousands of other RV's have already made it down that hill!

Do not expect to be able to slow down from your initial speed....

TRUE! As what everyone said above. If you are even starting to get nervous - using your trailer's brake controller for a few quick squeezes is a very good tactic. AND so is testing it before you need it. Having your muscle memory know where it is rather than having to look away from the road to find it is a "must have" skill in an emergency - so use it briefly at the start of each day's tow (you might discover your umbilical isn't in tightly too!). If you're really nervous - turn on your flashers - better to have a testosterone poisoned truck driver KNOW you're a born coward than to have him/her crowding your bumper trying to get you to speed up. ALWAYS let an aggressive driver pass you if there is any way to do so!

Paula

[Sbb]

We have not really driven very much on those grades, I have dumb question, I drive a 2103 2500 Suburban with brake controller part of the dashboard, not an add on. Where do I squeeze or how do I squeeze the brakes to test? Do I use the plus minus push buttons by it? I have it set at 3.5, not even sure that is correct. I drive fully loaded TV, a normal loaded Bambi 19' 2006. Thanks for help.

[bel73]

If you are new to towing or just don't have much experience, pick up a CDL study guide from your local DMV. There is a lot of very good info on driving techniques in all conditions.

Or click on this link to the Illinois guide. https://www.cyberdriveillinois.com/p.../dsd_cdl10.pdf

I would be very cautious using the trailer brakes to slow your vehicle down a mountain pass. Trailer brakes are not designed to slow both trailer and the tow vehicle. Say you start to use just the trailer brakes to slow down, it's now slowing you enough and your still gaining speed, so you grab a little more brake and it's still not enough. Now you decide to use the foot pedal to activate all the brakes. Your trailer brakes are already quite warm and now you just increased the chance to over heat them. That's all just my 2 cents though.

[Moflash]

With trailer hooked up increase gain until you can feel the trailer braking when brake pedal is depressed lightly while driving.You also should have two knobs that you can squeeze together with your thumb and forefinger to activate the trailer brakes and you use these when adjusting your gain.Dont be afraid to experiment with the gain to get it set just right.Your ideal gain setting is when the trailer brakes are activated just before your vehicle brakes engage.It is hard to get the trailer brakes to lock up so no worries when experimenting.My 2015 F350 is set at 7.5 but all vehicles are different.


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[Moflash]

Originally Posted by bel73

If you are new to towing or just don't have much experience, pick up a CDL study guide from your local DMV. There is a lot of very good info on driving techniques in all conditions.



Or click on this link to the Illinois guide. https://www.cyberdriveillinois.com/p.../dsd_cdl10.pdf



I would be very cautious using the trailer brakes to slow your vehicle down a mountain pass. Trailer brakes are not designed to slow both trailer and the tow vehicle. Say you start to use just the trailer brakes to slow down, it's now slowing you enough and your still gaining speed, so you grab a little more brake and it's still not enough. Now you decide to use the foot pedal to activate all the brakes. Your trailer brakes are already quite warm and now you just increased the chance to over heat them. That's all just my 2 cents though.

You are correct but a few brief intermittent pulses will not over heat the trailer brakes.That is why those activation knobs are there.The trailer will slow the combination down an save the tv brakes if used properly.

Common sense goes along way.



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[Rich Jenkins]

Good advice in this thread.

I forgot who told me this, but Interstate Highways are designed for a 6% grade apparently.

https://en.m.wikipedia.org/wiki/Inte...hway_standards

Point being, 'stay on interstates' might be advice worth following, since once you complete that initial descent without a change of underwear, you know it won't get any worse.

PS avoid crossing Death Valley in CA; we did this last month. We saw signs showing 9 1/2% grades. Yikes. It was No Fun.

[bel73]

Originally Posted by Moflash

You are correct but a few brief intermittent pulses will not over heat the trailer brakes.That is why those activation knobs are there.Common sense goes along way.



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A few quick pulses might not over heat the brakes, I agree. It will warm them up more than the tow vehicle and when things go wrong the trailer brakes will die first.

The knob on the controller should really only be used to test and adjust the brakes. Again, just my 2.

[Mrjkq]

Originally Posted by wulfraat

I live here in Colorado - pull through the mountains all the time - just came through Eisenhower tunnel to Denver a couple days ago - 12 miles or so total at 5-6% downhill grade... no big deal.

Just use 2nd & 3rd gear to keep your speed under 60mph on the straight aways and under 50/45 or less if the road / highway curves a bunch. Brake intermittently when needed. On long relatively straight stretches I like to brake firmly to take 5-10pmh off my speed... then use the gears... slowly coast back up to speed... then brake again, etc..

You'll be fine enjoy the views of beautiful CO!

I came through the "Ike" tunnels just last week on my was to Vegas. Kept my speed in check using the down hill assist & downshifting as needed. My 1500 RAM has an 8 speed tranny & I never had to get below 4th gear. I found that slowing it down at the top of the grade was the key to a safe decent.

[Moflash]

Originally Posted by bel73

A few quick pulses might not over heat the brakes, I agree. It will warm them up more than the tow vehicle and when things go wrong the trailer brakes will die first.



The knob on the controller should really only be used to test and adjust the brakes. Again, just my 2.

Do a little reading on the subject and you will find that the knobs are not there just for gain adjustment.These are designed for manual electric brake over ride and are used for controlling a swaying trailer and to reduce speed on a either slight or a steep hill.They are not designed for continuous usage and are only to be used as a temporary aid in these situations.Just another arrow in your quiver of trailer equipment.Learn to use them and you and you will be more comfortable in these situations.


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[TG Twinkie]

I would not use the brake controller to slow the whole rig down.
On grades steeper than 5% I shift my Tundra down to assist in slowing the rig.
I never tow over 60 mph and rarely drive in 5th or 6th. 4th is my preferred tow gear because it is the highest gear that is not overdrive.
I pay close attention to the yellow sign indicating recommended speed along with the standard speed limit signs. I will stay 5-10mph below those posted speeds.
I brake periodically to keep from exceeding my comfort zone.
If your Tundra is like mine and you are going too fast and attempt to shift into any gear lower than 4th you will hear a beep and it will not shift down.
The trick is to never allow the rig to get to the higher speeds. If the transmission and engine will hold you back let them do the work. If you find yourself pushing on the brakes for more than 5 seconds out of every 30 seconds you need to slow down and shift to the next lower gear.
Your Tundras brakes will dissipate the heat much faster than the trailer brakes. But if you overheat the trailer brakes to the point of failure then it's up to the truck brakes to slow or stop. Not a good position to be in.
Before descending any grade you should operate the brake controller manually for a second or two to make certain you can feel the trailer brakes engage.

[PKI]

Brakes on an appropriate TV will stop both trailer and TV. Most are disk and will provide more stopping force than the trailer drum brakes.

There was a time when brakes were poor and engine braking was needed to help slow a tow. There may even be an emergency loss of brakes that needs engine braking. However, unless the downgrade is 7-10%, you can maintain a 50-60 mph rate with steady soft pumping of the brakes. Slow down and coast in gear. When speed gets back up, slow again.

The TV engine brake apples force on the TV rear axle or the front and rear if 4x4. That lets the trailer run free and is not ideal. You need a properly proportioned brake controller that apples braking on the trailer with the TV to maintain alignment. The balance here is to not over use the drums on the trailer.

The brake controller application is needed to manually straighten out sway or align the trailer if it is over running the TV. Not usually the case.

A lower gear reduces the coast speed build up. A big diesel will maintain a steady down grade speed with minimal braking to settle the rig. A big gasser will slow some, but require more brake. A smaller engine will likely need more braking or a slower target speed on the down grade. The size of the rig, brakes, and available engine braking are all a balance.

We hardly use the engine to slow much. We start slow, coast up 5-10mph and gently brake back to our starting speed.

USA Interstates are about 5or6%. Western Canada has 6-7% grades.

A short down grade is not much to wory about unless there are significant turns as you go down. But long 7-10 mile grades, which are not usual, but do exist and therefore deserve a bit more care.

Suggest you discuss the techniques with veteran tow RVers and adjust for what your rig requires.

If you are not comfortable with the braking on your rig, aftermarket performance pads can offer improved performance. Disk brakes can be added to your trailer, but with reasonable care the drums should do the job.

A quick warning - be able to come to a complete stop on the down grade. It is not enough to just slow. If a vehicle pulls out or stops dead, you must avoid a collision. Be conservative, especially if there are blind turns.
Travel safe. Pat

[dkottum]

Be sure your trailer brakes are adjusted with enough gain on the controller to engage when stepping on truck brakes, then they will work together.

Start descent slow and stay slow, especially until you gain experience and confidence. Shift way down at the top of the grade, the engine will need to rev over 3500 rpm to get enough engine compression braking, that's what it's supposed to do. Add truck brakes which should also add trailer brakes together to maintain the chosen slow speed, do not let it speed above your chosen slow speed.

Stay in control of speed all the way; with experience you will be comfortable. The combination of engine compression braking, truck brakes, and trailer brakes will work well for you.

One note of caution. If the road becomes wet and slippery or icy, do not use engine compression (or exhaust) braking, especially without truck and trailer brakes at the same time. The trailer will always try to overtake the truck using only engine compression or exhaust braking, only the truck's rear tire traction is holding the truck and trailer. The trailer may push the truck into a jackknife condition if rear tire traction is lost.

[Blevi]

You're getting some great advice. I might also suggest the ordering a copy of that part of the country's Mountain Directory. We have the printed book versions and spend a lot of time in the mountains and canyons in Southern Utah and this is a must have to be able to know what you will be facing and when in terms of grades as well as roads to avoid.
http://www.mountaindirectory.com

[Seabloom]

Originally Posted by Sbb

We have not really driven very much on those grades, I have dumb question, I drive a 2103 2500 Suburban with brake controller part of the dashboard, not an add on. Where do I squeeze or how do I squeeze the brakes to test? Do I use the plus minus push buttons by it? I have it set at 3.5, not even sure that is correct. I drive fully loaded TV, a normal loaded Bambi 19' 2006. Thanks for help.

SBB

On your dash usually just above the +/- buttons there are two prongs that you can squeeze to manually check your brakes are functioning on the trailer only.

For me personally with my 2500HD GMC pick up and factory controller with my 1976 Overlander (27 ft) I have the gain typically set in the range of 6-7 depending on how much load I have in the trailer. I set my trailer brakes so that I can just barely feel them tug me when I tap the normal brake pedal. Setting them up prior to a trip is key. Your setting of 3.5 might be correct with the lighter trailer.

With all the above said if you have a Suburban 2500 and a 19ft trailer you should be in good shape. TV heavier than trailer is a safe thing. My truck and trailer are about equal. Truck might be a tad heavier.

Safe travels.

Kristien