Towing capacity

[pearlygate]

I am pulling a 2008 Keystone Cougar 244RLS (26') with a dry weight of 6,600 lbs., payload capacity of 3,390 and a hitch weight of 1,220.  My TV is a 2007 GMC Sierra LTZ with the 5.3 V8 and 3.73 axle.  It is rated at GVRW of 7,000 lbs., towing capacity of 7,500 lbs. and GCWR of 13,000 lbs. 
I weighed today at a Flying J and the front two axles (TV with RV attached was) 7,240 lbs. (full of gas) and the RV two axles were 6,080 lbs.  That was a total Gross Weight of 13,320 lbs. for the rig.

I still have several hundred lbs. to add to the camper weight.  I suspect when we are ready to leave I will be around 1,000 lbs. over what this Sierra is rated.

I'm curious to what some of you experts think is the risk as I start out on a 6,000 mile trip that takes me through the Rockies.

 

[silveradomike]

It is going to be slow going over the Rockies and if you push it you are going to fry your trans. I would try to shed a few hundred pounds. I would hate to see you cook the trans. Are you going with a full tank of water? Another issue is going to be your brakes. If you do pull this full load allow a substantial distance for stopping. The fact is your TV is too small for this trailer.

 

[edjunior]

Yup, I'm afraid you're a little out of your league with that truck.  Especially going through the Rockies.  In addition to risking the tranny, you may also have trouble with the brakes coming down.  You really need a bigger truck.

 

[Gary RV_Wizard]

We usually suggest staying 20% under the max tow rating when traveling in the western mountains, but you are going to be over weight before you even start.

The risks: overstressed and broken down transmission and drive train, smoking brakes in the downhills or unplanned stops, and poor emergency maneuvering. Even if you don't have a failure now, you are taking years of future life out of your truck by overloading it.

 

[longhaul]

Agree with the above replies.
IMO your imediate overweight issue is your most likely over the rear P tire capacity on those small semi float rear axles.
  P tires on a truck are required by fed law to be derated 10 percent weight capacity.
  If your going to keep and mod the truck I would recommend a LT load range C  @ 50 psi as a minimum or a LT D @ 65 psi if your wheels are rated for those pressures. 

A 1500 truck isn't a good canidate for carrying weights over the axle/tire limits.

 

[Blue Road Blogger]

As a person who ONCE hauled 8K pounds with a 5.7 auto trans 3:73 gears in a Sliverado down I-77, all I can say is OUCH.
If you are going over the Rockies, that would be rough.  Going through the Rockies?  I would have the trans upgraded and a BHTC (Big Honkin Trans Cooler) installed with an auxillary fan.

We currently haul 13K pounds with a diesel.  After coming down I-77 we swore we would never again haul that much with our 5.7 Silverado.  We are going to Yellowstone next year and have decided the diesel needs a few upgrades before we even think about the Rockies..

 

[Carl L]

In the West, that truck is going to be hurting.  A gasoline engine loses 3% of its rated horsepower for each 1000 feet of altitude that it is operating at.  If you take 1-70 over the Rockies for a horrible example you will top 11,300 feet at the Eisenhower Tunnels and 33% of your HP will be missing in action.  Even mooching around the Colorado Plateau at 7000 feet  will cost you 20% -- say at the Rim of the Grand Canyon or in the town of Flagstaff.

And then you need to go down the other side of the passes where you will encounter miles-long 6-7% grades -- on the freeways!  Lookout Pass in Idaho on I-90 is fixed in my memory forever. 

As a guy who has towed out here in the West for some 15 years, I would not take that rig into the mountains and plateaus of the West.

 

[Mopar1973Man]

And then you need to go down the other side of the passes where you will encounter miles-long 6-7% grades -- on the freeways!  Lookout Pass in Idaho on I-90 is fixed in my memory forever.

Ah that's easy stuff... Out here in Idaho I'm used to the 6% and 7% stuff... How about 16% Grade??? (Grin!)

http://i53.tinypic.com/ne9jq9.jpg

I'm use to hauling my utility trailer back and forth from 1,800ft to nearly 8,000ft for firewood... As for the travel trailer yeah getting up and down some of the roads out here with tight turns and 6-7% grade can be a real chour for even a modified Dodge Cummins diesel.

 

[raytronx]

Also consider wind, I've had some of the most problems towing against the wind on a long slow grade, that's where the heat can really build and the truck works hard. I recently came across the western  states on I90 with my F350 pulling 9000 lbs , the truck is rated to pull 13,500 lbs and I wished I had more truck. Had to pull off near the top of Lookout Pass and let her cool down before finishing the climb. Times it's windy, hot out and long slow grades I really have to pay attention to the heat, I would definitely not want to go out west with less truck.

 

[VallAndMo]

Hi,

[...]with my F350 pulling 9000 lbs , the truck is rated to pull 13,500 lbs and I wished I had more truck. Had to pull off near the top of Lookout Pass and let her cool down before finishing the climb.

That really got us worried, as this is almost exactly the combination we were looking for (5thWheel on the 9000-11000lbs range pulled by a 3/4 or 1-ton PU diesel truck). We thought we would have more than enough truck for any situation, but your post shows otherwise...

We've been doing some research, and we see (from your signature line) that you drive a 1994 F-350 with the 7.3 IDI Turbo Diesel... can you please tell us whether it's the powerstroke engine (525lb/ft peak torque) , or the pre-powerstroke one (360lb/ft)?

Thanks in advance,
--
  Vall & Mo.

 

[raytronx]

It's the pre power stroke 360 ftlbs international motor, so anything more modern should have a lot more juice and be plenty, everything else about the truck is great, braking is no problem, and it tows really stable, no sway even when big semis pass by on the interstate. Coming down the steep grades I just take it out of overdrive and and I only have to tap the brakes once in a while. the motor is bone stock and I have read about a few mods that can give it more power, for example the turbos down pipe was squished to get it by the firewall and a lot a people replace it with an aftermarket and also bigger exhaust and get more ummmph out of her. I've read theories that ford detuned this motor so it's new power stroke that was coming out would not be less horsepower than the international it was replacing. Anyway I never did overheat it just was careful, It made it through the Rockies just didn't fly up those passes like some of the newer trucks passing me, 

 

[VallAndMo]

It's the pre power stroke 360 ftlbs international motor, so anything more modern should have a lot more juice and be plenty

We checked and saw that the newest Powerstrokes  (2005+ 6.7/) sport 800ftlbs of torque, so we presume we should be alright! 

everything else about the truck is great, braking is no problem, and it tows really stable, no sway even when big semis pass by on the interstate. Coming down the steep grades I just take it out of overdrive and and I only have to tap the brakes once in a while. the motor is bone stock and I have read about a few mods that can give it more power, for example the turbos down pipe was squished to get it by the firewall and a lot a people replace it with an aftermarket and also bigger exhaust and get more ummmph out of her. I've read theories that ford detuned this motor so it's new power stroke that was coming out would not be less horsepower than the international it was replacing. Anyway I never did overheat it just was careful, It made it through the Rockies just didn't fly up those passes like some of the newer trucks passing me,

Thanks for all the info.

Cheers,
--
  Vall & Mo.

 

[R. J. Barton]

We checked and saw that the newest Powerstrokes  (2005+ 6.7/) sport 800ftlbs of torque, so we presume we should be alright! 

Thanks for all the info.

Cheers,
--
  Vall & Mo.

Just so you're clear, the 6.7 PSD just came out. Up until the 2008 model year Ford used the 6.0, then switched to the 6.4, then in 2011 came out with the 6.7.

I tow with a 2006 F250 CC FX4 with the 6.0. So far it's been great, but before I attempt the Rockies I'm going to have the Bullet Proof Diesel oil and EGR coolers installed.