Mountain Towing

[bogie514]

I am planning on taking an extended trip that will include time in Leadville, Colorado at 10,000 ft, and other western states. I am looking for advice from those who have done mountain and high altitude towing with a similar set up to what I have (see below). Will this be safe and dowable? I will be will under my max payload and tow rating by a wide margin. I did tow my old pop-up with a minivan through the mountains years ago - a case of ignorance is bliss.

Using the formula below, I understand that by the time I hit 7000 feet I will have lost 68 hp.

% HP LOSS = (ALT x 0.03 x 1) / 1000

Tow vehicle: 2008 Silverado 1500, Crew Cab, 5.3 L, Z71, 3.73 gear, Prodigy Brake controller (about 10 years old - can't remember the model number)

Camper: 2016 Freedom Express 231RBDS, 26'10", 5100lbs unloaded, 6100lbs estimated loaded.

My old camper was about 900 lbs less than my current camper. I was surprised how much of a difference that 900 lbs made when going uphill. On the flat I can't tell any difference.

Tom

[atwowheelguy]

My only experience was towing this 2800 lb. 6x14 in Colorado with a 3.5 Ecoboost with 3.55 axle. No sweat whatsoever pulling it all over the San Juan Mountains. 16 mpg too! 4600 mile round trip from Georgia, including 1400 miles in the CO mountains.

The hp loss at altitude is the reason I and most other high elevation dirt bike riders prefer 450cc and larger engines. We ride over some 13,000 ft. elevation passes. There the power is down 39% from sea level. My bike is 510cc, so it performs as a 311cc engine would at sea level. Too bad there are no Ecoboost dirt bikes.

Moderator edit to re-size pictures to forum recommended limit of 640px maximum width

[atwowheelguy]

GordonThree wrote:
I never noticed HP loss at altitude... my tiny trailer is far too light for the hemi to notice it by weight alone.

what it does notice is a head wind. I forget what highway it was, coming out of Vegas toward death valley, a really long moderate grade climb to only about 5000-6000ft? STRONG wind from the West, as I was heading west. This was the only time I've taken pitty on the hemi and backed off from the speed limit as I watched the oil and trans temps climb into the upper 25 (percent) of the gauge.

I don't have a manual transmission, I don't pretend to have one either, playing with the gears. I occasionally downshift on steep downhill grades when tow-haul doesn't for some reason (usually it does automatically)

just my 5cents

oops, forgot good sam inc. doesnt like percent signs

Enter the forum through https://www.woodalls.com

It will allow the % sign. See, it worked!

[Hybridhunter]

I towed all over Colorado, including Eisenhower pass with my previous 3.7 4X4 SCAB F150. Similar horsepower, but 3.73 gears and a 6 speed. We were towing a trailer that was around 4K lbs, very tall, boxy (lifted for off-roading and not an easy tow) and an ATV in the bed of the truck. On the Interstate, we were always able to go 65 mph, sometimes it was a 6500rpm, but I'm not one who worries about such things, put the hammer down and let the truck work. We were pretty much maxed out, but it didn't get hot, and it did the job.
My only concern with the Chevy would be the transmission, as I really don't trust the GM 4L60, but that's a whole 'nother discussion.

[COnative]

I think you'll be fine with your set up. On I-70, without a diesel, I think you have to keep your momentum up and look for safe opportunities to get around the big rigs as the climbs approach. Those being the Gennesee area which is just west of Denver as you hit the foothills. The Georgetown area has a nice steep grade on the west end. Also just before the Eisenhower tunnel it gets steep and then Fremont pass (91) up to Leadville has some nice grades.

Years ago when I towed with a dodge 5.9, 3.92 gears, I'd try to do my towing in the mornings and sometimes chart my course up the river valleys instead of hitting I-70. That truck would climb these passes in 2nd gear, sometimes dropping to 1st and I'd be lucky to hit 25-30 mph. You could hit 50 west out of Pueblo to 285 to 24 and on up to Leadville. Alot longer trip but less strenuous. Love the Arkansas river valley and Salida area which you'd pass through going this way. Like everyone has said, new fluids and good tires and you will be good to go on any route you choose.

[time2roll]

Happy Prospector wrote:
Lots of half ton trucks being towed in from going up or down the long Colorado passes. Make sure your towing insurance is up to date and bring a credit card for the repairs. Good luck and besides what could possibly go wrong?

Any real statistics that half-ton vehicles towing in CO are less reliable than anything else?
My FUD meter is off the scale.

[Happy_Prospecto]

Lots of half ton trucks being towed in from going up or down the long Colorado passes. Make sure your towing insurance is up to date and bring a credit card for the repairs. Good luck and besides what could possibly go wrong?

[Lynnmor]

dave17352 wrote:
Totally agree with engine braking. When going down the mountain grades I use the gear that will keep at or below my desired speed. I have the chevy exhaust brake or what ever it is now and it helps a ton. But when I didn't I kept total control with the gear down tactic. I learned it the hard way when we just about completely lost our brakes in a 1988 27 foot jamboree class C, going down some real steep mountain grades, I think by Yellowstone. I was seriously considering turning into the mountain because my brakes were about completely gone and we were on never ending desending switchbacks. I thought I was being careful and not riding the brakes. The local mechanic came out and bled my brakes up on the mountain. He said he was up there all the time. For just that reason. He is the one who told me you should really use your brakes hardly at all while descending with a heavy load. He also said if you are going fast down a mountain with a heavy load and more less have to make a panic stop. The second time you try you may not have brakes. I continued on our trip and used his advice and really barely touched the brakes on steep descents, I let the tranny do all the work. Worked great. Nothing like the feeling of you brakes going to the floor with the whole family in a RV going down a winding mountain grade. YIKES

I think the "stab" braking folks should read and re-read what you wrote. Brakes are a heat device that turns the kinetic energy into heat that must be transfer to the air. No matter how one plays with the brake pedal, the fact is that you should use the brakes as little as possible on mountain roads.

[dave17352]

Totally agree with engine braking. When going down the mountain grades I use the gear that will keep at or below my desired speed. I have the chevy exhaust brake or what ever it is now and it helps a ton. But when I didn't I kept total control with the gear down tactic. I learned it the hard way when we just about completely lost our brakes in a 1988 27 foot jamboree class C, going down some real steep mountain grades, I think by Yellowstone. I was seriously considering turning into the mountain because my brakes were about completely gone and we were on never ending desending switchbacks. I thought I was being careful and not riding the brakes. The local mechanic came out and bled my brakes up on the mountain. He said he was up there all the time. For just that reason. He is the one who told me you should really use your brakes hardly at all while descending with a heavy load. He also said if you are going fast down a mountain with a heavy load and more less have to make a panic stop. The second time you try you may not have brakes. I continued on our trip and used his advice and really barely touched the brakes on steep descents, I let the tranny do all the work. Worked great. Nothing like the feeling of you brakes going to the floor with the whole family in a RV going down a winding mountain grade. YIKES

[270wsmhunter]

When we went through the Big Horn mountains we had a stock 2008 GMC 1500 crew cab 4x4 with 5.3 and 3.73 rearend pulling a Jayco 26BH. It did the job but wasn't very happy about it at times. We were often around 15-25 mph going up with transmission temps as high as 240F with the reduced air flow over the cooler. I left my transmission temp on the DIC displayed all through the trip. Before going on that trip I spoke with my local GMC dealership and was told 240-250F was ok for moderate periods of time. He had told me that transmission overtemp/warning was at 270F. We upgraded to a HD after that but if I had kept that truck I would've put LT tires on it and an electric fan to push air across transmission cooler in low speed pulling.

Just make sure everything is in order and maintained. Don't be afraid to let your truck pull some RPMs and do downshift on the down grade to save on brakes.

[dodge_guy]

You'll do just fine. I was towing a 6500lb loaded TT with a 97 Dodge conv. Van. It had the 5.9L and 3.90 gearing.

Enjoy your trip.

[IdaD]

The real key in mountains is going down them. Downshift and use engine braking, and if you need to supplement with brakes do so in intervals and don't ride them continuously or they'll overhead and won't work very well.

Going up hills will be slow at times. Use the right lane if there is one, and use pull-outs to let others pass periodically if you're on a narrow mountain road. People get agitated following a slow RV going 25 MPH up a long grade when they don't utilize pullouts, and that often prompts some stupid decisions in terms of trying to pass where it isn't safe.

[JIMNLIN]

op wrote:
I am planning on taking an extended trip that will include time in Leadville, Colorado at 10,000 ft, and other western states. I am looking for advice from those who have done mountain and high altitude towing with a similar set up to what I have (see below). Will this be safe and dowable?

You'll be fine.
I pulled a 26' 5th wheel trailer all over the mountains in CO and northern NM with a '90 chevy 5.7 TB engine with a whoppin' 205hp/300 ft lbs torque. We made Wolf Creek pass/Monarch Pass/Red Mountain Pass/Independence Pass/Ike tunnel all in the 10000'-12000' range.
Your '08 FI 5.3 engine has around 300 hp and your towing a 6k trailer. I wouldn't add a thing to the truck other than fresh oil & filter/air filter/replace old rad hoses and new thermostat.
Just take your time and don't worry about staying up with the new gen diesels or the fast track lanes.

[Lynnmor]

bogie514 wrote:
I will be adding a cold air intake,

Save your money, and your engine. Skip that piece of junk intake.

[pitch]

In 1958 my granparents towed a TT across the Rockies with a Buick . That car had probably less than 100 hp. They made it!