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Topic: Steep Grades for towing TT

Posted By: grittyoctopi on 06/29/12 03:05pm

What are the steepest grades that you routinely have to climb towing your TT in mountainous areas?(and come down)
Thanks,

cliff


Posted By: ScottG on 06/29/12 03:08pm

6% ~ we like to camp on the other "dry" side of the state but there's a mountain range between us. This is the main reason we have a diesel. Power to climb and an exhaust brake for coming down.


Scott, Grace and Wesly
2003 Dodge 3500 4x4, 6 speed Cummins (lightly bombed),
2004 Forest River 25RKS many, many mods.
POS H0NDA eu2000i


Posted By: opnspaces on 06/29/12 03:17pm

6% is the steepest I've pulled my TT. Probably a lot steeper pulling the PU.


1996 Suburban 4x4. 350, 4.10 3/4 ton
2005 Jayco Jay Flight 27BH
1986 Coleman Columbia Popup.


Posted By: smkettner on 06/29/12 03:14pm

Routine would be 6%. Have gone 10%.


2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675 watts solar
Send a PM if I missed something


Posted By: dbbls on 06/29/12 03:24pm

Very rare to find a grade over 6%, but they are long.


2011 F-350 CC Lariat 4X4 Dually Diesel
2012 Big Country 3450TS 5th Wheel


Posted By: Bonefish on 06/29/12 03:30pm

Towed up and over Wolf Creek Pass.....I think the max was 8% grade.






Posted By: djgarcia on 06/29/12 05:34pm

What are the steepest grades that you routinely have to climb towing your TT in mountainous areas?(and come down)
Thanks,

cliff

If you have a diesel engine, be sure you have an exhaust brake installed!!! Saves your brakes and white knuckles


Dick
djgarcia1939@gmail.com




Posted By: Gdetrailer on 06/29/12 03:40pm

dbbls writes "Very rare to find a grade over 6%, but they are long."

Depends on where you are in the country and the terrain of that area, some states are more like rolling hills and some are more like pure mountains and anything in between.

In PA, I have one nearly in my backyard at 9% for 1/2 mile.

In W VA and VA have found several at 6%-7% up to 7 miles in length.

In VT I have run into quite a few 10%-11% grades for as short as one mile to as long as 5 miles.


Posted By: the bear II on 06/29/12 03:52pm

Cliff,

I'm going to read between the lines on your post and guess that you may be concerned about towing up and down a steep grade. I looked back at some of your previous posts and most of your questions are the type someone new to RVing or towing would ask.

Maybe this will put your mind at ease. The rule of thumb when towing uphill is to drop down a gear when your engine is lugging. You may have to go all the way down to first gear on a really steep grade. I've gone up some 10% grades in first gear doing 15MPH in my old truck. The goal is to use the transmission gears to keep you engine from having to work too hard.

Rule of thumb for going downhill is to use the same gear you had to go uphill in. So on that 10% percent grade, I went down it in first gear at about 20MPH.

There is a braking technique used by truckers when going down a steep hill. It's known as the Aggressive Braking Technique. You determine what maximum speed you feel is safe. As your RV builds up speed going downhill you wait until it gets 5 - 10MPH above your safe speed and then apply the trailer brakes and tow vehicle brakes hard until the speed drops to 5-10 MPH below your safe speed. You let off the brakes and then watch for the speed to get above your safe speed and apply the brakes hard again, not skidding hard but enough to slow down quickly to get to 5-10 MPH below your safe speed. You repeat as needed. This helps give time for your brakes to cool in between applying them.

If you get to your 5-10 MPH over the safe speed too quickly and are having to use the brakes too often you may need to go to a lower gear.

I often travel a mountain road where it goes from near 6000 feet down to 1000feet in a series of 6 to 10% grade switchbacks. I do it in first gear and only have to use the aggressive braking about 5 times. It takes me nearly an hour to get down the hill. But I have strong brakes, not overheated brakes when I get to the bottom. It's great for enjoying the scenery along the way.


Posted By: korbe on 06/29/12 03:58pm

I will easily pull up a local 10% grade, but I could not hold compression on the way down. Needed to use my brakes more than I wanted.


2004 F250 SD PSD
2004 Crossroads Cruiser CF25RS



Posted By: dahkota on 06/29/12 04:19pm

We've done the road into Ricketts Glen State Park in PA - 18% grade. The one into Ohiopyle in PA is around 12%. We did that last weekend. It is worse coming down than going up if only because of the banked curve right up against a mountain.

those are the two most notable we recently traveled. But there are quite a few in the MD/PA/WV area of the Appalachians.


2008 Ford F250 diesel
2014 Fleetwood Bounder 33C
States camped, 2014: 22


Posted By: Searching_Ut on 06/29/12 04:58pm

Routine for freeways very rarely exceeds 6 percent for any significant distance, but there are a few exceptions of course. Steep pulls on highways out west often run 8 percent, with some of the shorter sections getting up to 12 percent on occasion. The steepest grade signs I recall seeing were 25 percent on a few off the beaten path roads, and they were for short little distances where the road traversed ravines or canyons.

If you're wondering about the affects on the vehicle, my experience with an underpowered vehicle is that around 8 percent or so you might drop down into first gear, by 12 percent you'll be possibly running out of rpm and may have to use 4 low to turn around. With my diesel towing 7 or 8 thousand pounds I generally can maintain posted speed limits at up to 8 percent then start slowing down fairly fast after that.

Max you can drive in a vehicle on slickroack in a place like moab, in excess of 100 percent. I used to have a little tilt gauge on the dash of my polaris RZR, and you could exceed 45 degrees (100 percent for grade) if the traction was right. You might want to use straps though as thats right around the tip over angle sideways and within 10 degrees or so front or back. With a little popup modified for off roading and a modified truck I've probably exceeded 50 percent but I never had the means to measure.


Posted By: gmw photos on 06/29/12 03:35pm

I was up and down a couple of 7% grades last week in Colorado and Wyoming. Pulling a 19' Funfinder ( 3800 pounds ) with a Nissan Frontier, 4.0 gasser, six speed manual. Was able to climb in third or fourth, and came down in third. Coming down in third, the engine held it to between 40 and 45 mph without using the brakes.


Posted By: beckid on 06/29/12 03:30pm

Just went over ALOT of 7% grades in SD and Wyo. Knuckle biting I tell ya...and the wind did not enhance the experience in a positive way whatsoever.


Me '54
Him '58
Maggie the wonderdog
2008 Fleetwood Fiesta LX 34N



Posted By: smkettner on 06/30/12 08:16pm

My wimpy 1/2 ton rotors have 177,000 miles on them.
I have been down plenty of 8 to 10%+ hills, braking is never an issue, no white knuckles what ever that is.


Posted By: atreis on 06/29/12 05:47pm

Routinely: 6 and 6.5% (I-68 through Maryland - never below 45mph). I've gone as steep as 9%, but not far enough to know how the setup would do on a long pull at that grade.

I imagine there's a point where having front wheel drive would start to cause problems with the backward lean, but I've not hit it yet (and would naturally avoid the roads that are known to be especially difficult).


2009 Trail-Sport TS21RBH
2008 Toyota Sienna



Posted By: old guy on 06/29/12 05:50pm

Ask any OTR truck driver about Cabbage Hill in eastern Oregon. It is one of the notorious hills in the nation. It is even worse than the grapevine in Cailf. Most recently they made it three lanes up and three down. Makes it a lot easier to get up the hill, since many truckers like to pass on up hill grades. Most be a quantification to being a true OTR driver. always pass on a hill only. never pass on the level


Posted By: Bull Rider on 06/29/12 10:23pm



McNeil Canyon, just outside of Chelan WA


If you receive help from other members, don't forget to update your topic with the results.



Posted By: HappyTrails2U2 on 06/30/12 05:12pm

Here's a white knuckle road with a 26% grade.





30% would be suicide!



* This post was edited 06/30/12 05:19pm by HappyTrails2U2 *


2010 Rockwood Signature Ultra Lite 8315BSS
2003 Chevy Silverado 1/2 Ton Extended Cab



Posted By: E&J push'n wind on 06/30/12 06:09pm

Searching_Ut wrote:

No flames, except maybe coming off the brakes. My point isn't that you can't do it without the diesel, it's just that the diesel makes it a sunday drive in the park vs possible white knuckle. 10 mile decent in my old gasser on 8 percent grade required close watch of tach to keep engine from exceeding 6k rpm, many hard brake applications, possibly pulling over to let things cool if I had to get on them too much, and on that truck I ended up replacing the brakes, and generally front rotors every 40k or so as I play in the mountains a lot and I would eat up pads, and tended to warp the rotors. Same road with the diesel, Control speed with engine, maybe a little braking going into tight curves, but no where near having to apply them hard enough to worry about heat, virtually never pushing the truck hard enough to worry about over reving the engine. You end up enjoying the scenery, and only have to focus on keeping everything on the road, same as motoring down the freeway.


I'd agree with you Seaching, a bigger truck can make for a more enjoyable drive. I just don't want folks to make the mistake and think that a bigger truck can't get away from them because it has an exhaust brake or bigger brakes on it. My only point is knowing your limitations and driving accordingly.

I'm one of those driving with a 1/2 ton and I'm probably pushing the limits of my TV. In fact, the brake controller I had previously didn't work worth a squat so most of the braking I was doing was occuring on the TV. I never once felt I was out of control because I always kept my speed in check using the transmission to keep my speed down and brakes to keep it where I wanted it. My last trip before changing controllers was in the Big Bear, CA area and there was lots of climbing and descending between 6% and 8% and even mistakenly took a wrong turn and put my self on a 10%er. Had to turn around and go back down it with that sorry brake controller.

I think most folks just want to drive their TV's like any Sunday drive while towing. Just put it in "D" and go but you know and I know that there is much more to it than that. You have to learn to select the gear you should be in, more so when descending than climbing. More often than not the tranny will down shift when climbing but rarely will the tranny down shift when descending. That's when you gotta think for the ECU because they haven't been programed for towing down hill. This is not in all cases but I'd say in the vast majority of gassers. I understand that some if not all the diesels will maintain the speed you set them at when descending, even that can be dangerous though.

So, for those new to towing. Know your limitations and keep your speed in check when mountain driving.


Wisdom is the right use of knowledge. To know is not to be wise. Many men know much, and are all the greater fools for it. There is no fool so great a fool as a knowing fool. But to know how to use knowledge is to have wisdom.

Charles Haddon Spurgeon



Posted By: E&J push'n wind on 06/30/12 03:13pm

Searching_Ut wrote:

Lowsuv wrote:

Best argument for diesel over gas is right here.
Braking.
2500HD Duramax has huge disk brakes all around.
Go to your tire store and check out the wimpy brakes on the half ton pickups.
Obviously, diesel compression works great to save your brakes for when you are surprised and actually need them because the drum brakes on your trailer have overheated and lost 50 % of their capacity.


That is so true, other than maybe the compression part as it's the exhaust brake on my 2011 Dodge that makes all the difference in the world. The Engine compression braking is not particularly great. I drive regularly on many of the roads I keep seening folks considering to "dangerous" to take an RV on, and find most of the time decending on grades of 8 percent or less or my primary means of controlling my speed is the gas pedal rather than the brake, even on the roads with the constant cautionary speed limits well below 35mph. On freeways, and most highways which tend to be less steep and straighter, you can use cruise control even on the decents. I've become quite the diesel fan in the 10 months and 7 thousand towing miles I've owned mine.


I'm gonna be the odd man out on this one!

I disagree with both of you on this. Sure the 3/4 and 1 ton trucks are gonna have bigger brakes, they should as they have a higher load rating capacity as does a semi with drum brakes mind you.

So before anyone starts in on me and tries to flame me, I've got an unrestricted CDL, air brake certified and have a passenger and tanker endorsement. Have an MC endorsement too FWIW! Anyway, braking is really just being smart about what you are doing and not letting your speed get away from you whether you are in a semi, motor coach, 1 ton, 3/4 ton or 1/2 ton. Keep your speed under control by using your gears, exhaust brake or not, and when you do need to scrub off speed. Use all brakes simultaniously, not just trailer brakes.

Last trip out we saw a semi with trailer brakes on fire and smoke pouring off of them because the driver was riding just trailer brakes. Other semi's going down that same grade were having no problems.


Posted By: anaro on 06/30/12 07:00pm

HappyTrails2U2 wrote:

Here's a white knuckle road with a 26% grade.





30% would be suicide!



No thanks. Not even with the diesel would I ever think to try these.


2014 Silverado 3500 Duramax, SRW, Crew Cab, 4WD
2014 Palomino Sabre 34REQS
2011 Crossroads Zinger ZT26BL - sold after 3 1/2 yrs and 76 nights camped in it!


Posted By: anaro on 06/29/12 08:19pm

Have come across a couple of 7% grades in NC/VA. Follow The Bear II's advice on how to handle the hill... or are you worried about your TV/TT combo on the steeper grades? If that is the case, don't even try it. I have been pushed down a 7% grade by a poorly matched combo. That was way to scary and risky. Never again will that happen to me.


Posted By: Desert Captain on 06/29/12 08:37pm

Just returned from another trip up to the White Mountains. The 180 mile trip (one way), includes multiple 6, 7 and 8 percent grades. Several are 8 to 12 miles long. Coming south from Globe on Highway 77 there is a 12 mile grade that starts out as 7 percent, five miles down the grade there is a run away truck ramp. The grade increases to 8 percent and one mile from the first is a second run away ramp. Taking 177 out of Winkelman you will encounter three ten percent grades, one of which is several miles long. Not sure i can remember what flat road looks like.


Posted By: Searching_Ut on 06/30/12 04:12pm

E&J push'n wind wrote:

Searching_Ut wrote:

Lowsuv wrote:

Best argument for diesel over gas is right here.
Braking.
2500HD Duramax has huge disk brakes all around.
Go to your tire store and check out the wimpy brakes on the half ton pickups.
Obviously, diesel compression works great to save your brakes for when you are surprised and actually need them because the drum brakes on your trailer have overheated and lost 50 % of their capacity.


That is so true, other than maybe the compression part as it's the exhaust brake on my 2011 Dodge that makes all the difference in the world. The Engine compression braking is not particularly great. I drive regularly on many of the roads I keep seening folks considering to "dangerous" to take an RV on, and find most of the time decending on grades of 8 percent or less or my primary means of controlling my speed is the gas pedal rather than the brake, even on the roads with the constant cautionary speed limits well below 35mph. On freeways, and most highways which tend to be less steep and straighter, you can use cruise control even on the decents. I've become quite the diesel fan in the 10 months and 7 thousand towing miles I've owned mine.


I'm gonna be the odd man out on this one!

I disagree with both of you on this. Sure the 3/4 and 1 ton trucks are gonna have bigger brakes, they should as they have a higher load rating capacity as does a semi with drum brakes mind you.

So before anyone starts in on me and tries to flame me, I've got an unrestricted CDL, air brake certified and have a passenger and tanker endorsement. Have an MC endorsement too FWIW! Anyway, braking is really just being smart about what you are doing and not letting your speed get away from you whether you are in a semi, motor coach, 1 ton, 3/4 ton or 1/2 ton. Keep your speed under control by using your gears, exhaust brake or not, and when you do need to scrub off speed. Use all brakes simultaniously, not just trailer brakes.

Last trip out we saw a semi with trailer brakes on fire and smoke pouring off of them because the driver was riding just trailer brakes. Other semi's going down that same grade were having no problems.


No flames, except maybe coming off the brakes. My point isn't that you can't do it without the diesel, it's just that the diesel makes it a sunday drive in the park vs possible white knuckle. 10 mile decent in my old gasser on 8 percent grade required close watch of tach to keep engine from exceeding 6k rpm, many hard brake applications, possibly pulling over to let things cool if I had to get on them too much, and on that truck I ended up replacing the brakes, and generally front rotors every 40k or so as I play in the mountains a lot and I would eat up pads, and tended to warp the rotors. Same road with the diesel, Control speed with engine, maybe a little braking going into tight curves, but no where near having to apply them hard enough to worry about heat, virtually never pushing the truck hard enough to worry about over reving the engine. You end up enjoying the scenery, and only have to focus on keeping everything on the road, same as motoring down the freeway.


Posted By: Searching_Ut on 06/30/12 10:45am

Lowsuv wrote:

Best argument for diesel over gas is right here.
Braking.
2500HD Duramax has huge disk brakes all around.
Go to your tire store and check out the wimpy brakes on the half ton pickups.
Obviously, diesel compression works great to save your brakes for when you are surprised and actually need them because the drum brakes on your trailer have overheated and lost 50 % of their capacity.


That is so true, other than maybe the compression part as it's the exhaust brake on my 2011 Dodge that makes all the difference in the world. The Engine compression braking is not particularly great. I drive regularly on many of the roads I keep seening folks considering to "dangerous" to take an RV on, and find most of the time decending on grades of 8 percent or less or my primary means of controlling my speed is the gas pedal rather than the brake, even on the roads with the constant cautionary speed limits well below 35mph. On freeways, and most highways which tend to be less steep and straighter, you can use cruise control even on the decents. I've become quite the diesel fan in the 10 months and 7 thousand towing miles I've owned mine.


Posted By: parkersdad on 06/30/12 06:10am

My Hemi coming down the mountain from Blowing Rock NC geared down and kept me slow. I was shocked I didn't have to use my brakes much.


Posted By: WyoTraveler on 06/30/12 06:33am

the bear II wrote:

Cliff,

I'm going to read between the lines on your post and guess that you may be concerned about towing up and down a steep grade. I looked back at some of your previous posts and most of your questions are the type someone new to RVing or towing would ask.

Maybe this will put your mind at ease. The rule of thumb when towing uphill is to drop down a gear when your engine is lugging. You may have to go all the way down to first gear on a really steep grade. I've gone up some 10% grades in first gear doing 15MPH in my old truck. The goal is to use the transmission gears to keep you engine from having to work too hard.

Rule of thumb for going downhill is to use the same gear you had to go uphill in. So on that 10% percent grade, I went down it in first gear at about 20MPH.

There is a braking technique used by truckers when going down a steep hill. It's known as the Aggressive Braking Technique. You determine what maximum speed you feel is safe. As your RV builds up speed going downhill you wait until it gets 5 - 10MPH above your safe speed and then apply the trailer brakes and tow vehicle brakes hard until the speed drops to 5-10 MPH below your safe speed. You let off the brakes and then watch for the speed to get above your safe speed and apply the brakes hard again, not skidding hard but enough to slow down quickly to get to 5-10 MPH below your safe speed. You repeat as needed. This helps give time for your brakes to cool in between applying them.

If you get to your 5-10 MPH over the safe speed too quickly and are having to use the brakes too often you may need to go to a lower gear.

I often travel a mountain road where it goes from near 6000 feet down to 1000feet in a series of 6 to 10% grade switchbacks. I do it in first gear and only have to use the aggressive braking about 5 times. It takes me nearly an hour to get down the hill. But I have strong brakes, not overheated brakes when I get to the bottom. It's great for enjoying the scenery along the way.


Excellent advise for those not familiar with towing on steep grades. The only thing I would add is when you are in a gear going very slow use your 4 way flashers so other vehicles know you are much slower than the traffic flow.


2013 Monaco Monarch
2012 Jeep Wrangler
AC6CV, ex-WN8RUR, ex-W8RUR, ex-K7RIO, ex-WB6GBR since 1954
Commercial 1st class Radio Telephone, & Telegraph certificate
ARRL 35 WPM Certificate.



Posted By: Lowsuv on 06/30/12 12:33am

Best argument for diesel over gas is right here.
Braking.
2500HD Duramax has huge disk brakes all around.
Go to your tire store and check out the wimpy brakes on the half ton pickups.
Obviously, diesel compression works great to save your brakes for when you are surprised and actually need them because the drum brakes on your trailer have overheated and lost 50 % of their capacity.


Posted By: relliott75 on 06/30/12 11:16am

Worst % I've seen was 19% grade in Branson Missouri, and by far the worst hill was a 15% grade over 4 miles on a washed out dirt road without guard rails and only 17 feet wide (people were coming up and going down!) it was a forced evac route due to closed highways to get out of Colorade Springs this past week because of their fire problems. 4WD was required, it was terrifying!


2007 Jayco 29FBS / GVWR 8800
2010 Dodge Ram 2500 6.7 CTD MEGACab 4x4 Laramie
Kansas City, Kansas
DW, 2 Kids & 100 pound GSD!


Posted By: Fabguy on 07/01/12 04:59pm

Lowsuv wrote:

Best argument for diesel over gas is right here.
Braking.
2500HD Duramax has huge disk brakes all around.
Go to your tire store and check out the wimpy brakes on the half ton pickups.
Obviously, diesel compression works great to save your brakes for when you are surprised and actually need them because the drum brakes on your trailer have overheated and lost 50 % of their capacity.


My 2500HD has the same disc brakes as the Duramax version, and the 8.1L does a very acceptable job at pulling my 9200 GVWR trailer both up and down the passes around here.


Jeff


2002 GMC Sierra 2500HD 8.1/Allison/4:10/Prodigy brake controler/Dual Cam HP

Pulling a 2004 Sprinter 274 RLS






Posted By: canoe on top on 07/01/12 03:49pm

Living in CO, we get plenty of, "experience", towing in the mountains. Also, on the Dempster Highway in the Yukon and Northweswt Territories, (450 miles of unpaved road into the arctic), there are 12% grades that can be exciting when it is raining as they turn to mud.

I agree with pretty much everything that has been said but, would add a couple of things. The easiest place to control your speed going down hill is at the top of the hill. Start down going very slow, (you can always speed up). If you come off the top of a hill at 60mph, you can reach 70 very quickly. Start down at 30-35 and you have a nice margin of control. I have, descending on snow,shifted into 4WD low range to keep my speed at 20mph or less.

Much easier to start at a slow speed and maintain it than to get going to fast and try to bring it back down.


Posted By: E&J push'n wind on 07/01/12 07:04pm

canoe on top wrote:

Living in CO, we get plenty of, "experience", towing in the mountains. Also, on the Dempster Highway in the Yukon and Northweswt Territories, (450 miles of unpaved road into the arctic), there are 12% grades that can be exciting when it is raining as they turn to mud.

I agree with pretty much everything that has been said but, would add a couple of things. The easiest place to control your speed going down hill is at the top of the hill. Start down going very slow, (you can always speed up). If you come off the top of a hill at 60mph, you can reach 70 very quickly. Start down at 30-35 and you have a nice margin of control. I have, descending on snow,shifted into 4WD low range to keep my speed at 20mph or less.

Much easier to start at a slow speed and maintain it than to get going to fast and try to bring it back down.


Bingo, that's it right there! You hit the nail on the head!

Again, knowing your limitations for the conditions you have to work with. Raining on a 12% muddy hill, whoah!! I'm not sure I'd want to take just my TV alone down that! Just kidding..,

Some conditions may start you out slower and some may allow a bit faster. There are a lot of variables each will have to consider when towing their trailer and only you will know what is safe based on your load and those variables.


Posted By: Downwindtracker2 on 07/02/12 11:04pm

Canoe On Top got it right. When you do 12% on gravel with no barriers,you come down real slow. On mud,I would wait until it dries.


Adventure before dementia


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