Thinking on a new truck... thinking on gas vs diesel...etc.At the moment we need tow capacities in the 13,000 - 15,000lbs trailer weight range with 13ft high frontal area...We live just above 2000ft elevation (lots of windy days too) and most of our TC hauling and 5th wheel towing happens from 2000ft - 7000ft and we haven't travelled Colorado yet...Watching the manifold pressure (sorry "Turbo Boost" sounds more powerful doesn't it?) on the diesel engine I see it "normalizes" at various altitudes (stays the same) which means the engine maintains it's power output. Plugging in some advertised numbers and altitudes to this calculator I see the 6.4 Hemi I like (410HP at 5600rpm) would be 50HP down at 2200ft and over 100HP down above 8000ft...HP at altitude calculator clickyProlly have to wait for F150's turbocharged, direct injected, Vsomething MegaEcoBoost bigger brother to enjoy spark plugs...

If you want to pull that kind of weight at that attatude there is only one answer and it doesn't have spark plugs!It if you chose correctly it won't even have glow plugs (sorry personal opinion on Cummins)! Get yourself anyone of the new diesels and enjoy the tow!

I'd suggest a turbo diesel for that kind of weight at altitude.

Towing relatively heavy and in the monuntains, diesel is the way to go. Ford's towing guide on line website has excellent information about the loss of power and towing capacities for gas engines by altitude. A travel trailer and certainly a fifth wheel has frontal area considerations as well and those are also addressed on their website. The Ford guide specifies a two percent reduction for each 1000 feet altitude gained for normally aspired (non turbocharged) gas engines and no reduction for turbocharged diesels.

06Fargo wrote:Thinking on a new truck... thinking on gas vs diesel...etc.At the moment we need tow capacities in the 13,000 - 15,000lbs trailer weight range with 13ft high frontal area...Keep it simple and think Diesel.

It's not gas vs. diesel that is the difference. A turbocharged gasser will maintain higher % of power at higher altitudes too. There just have not been many turbocharged gas engines in thee history of pickups. F-150 Ecoboost does very well at altitude.

HP vs altitude & gas vs diesel | Good Sam Community

Targa
Explorer
Apr 25, 2014
I would go diesel in your situation.
Denny___Jami
Explorer
Apr 25, 2014
Dave H M wrote:
Denny & Jami wrote:
The trailer we are pulling last time I weighed it was 15901lbs and yes I pulling it with a gasser and just like all motors it has power lose at altitude. Newer gas motors adjust to the higher elevations on the fly unlike older models. But you can't run diesel gears in them, you have to gear them so they run in their power band when pulling grades, but when we are running down the interstate I can still run in 6th gear at 2K rpm at 65 mph. My not sure about the other brands but Fords 6.2 with the 6 speed and 4.30 gears is a very capable pulling platform.

If you want to give your truck a test take hwy 191 south of 80 in Wyoming to Flaming Gorge Lake in Utah. On our last trip we were from sea level to 10K feet and it was a pleasure to drive.

Denny

You are preaching to the choir Denny - in my opinion.

I am running the 6.2 with 4.30's in an F 250 towing 11.5K fifth wheel. I switched to gas.

You just have to relax when you see another diesel thread spooling up. :W

I'm just letting others know that there's other options out there :B

Denny
Dave_H_M
Explorer II
Apr 25, 2014
Denny & Jami wrote:
The trailer we are pulling last time I weighed it was 15901lbs and yes I pulling it with a gasser and just like all motors it has power lose at altitude. Newer gas motors adjust to the higher elevations on the fly unlike older models. But you can't run diesel gears in them, you have to gear them so they run in their power band when pulling grades, but when we are running down the interstate I can still run in 6th gear at 2K rpm at 65 mph. My not sure about the other brands but Fords 6.2 with the 6 speed and 4.30 gears is a very capable pulling platform.

If you want to give your truck a test take hwy 191 south of 80 in Wyoming to Flaming Gorge Lake in Utah. On our last trip we were from sea level to 10K feet and it was a pleasure to drive.

Denny

You are preaching to the choir Denny - in my opinion.

I am running the 6.2 with 4.30's in an F 250 towing 11.5K fifth wheel. I switched to gas.

You just have to relax when you see another diesel thread spooling up. :W
Denny___Jami
Explorer
Apr 25, 2014
rhagfo wrote:
Denny & Jami wrote:
The trailer we are pulling last time I weighed it was 15901lbs and yes I pulling it with a gasser and just like all motors it has power lose at altitude. Newer gas motors adjust to the higher elevations on the fly unlike older models. But you can't run diesel gears in them, you have to gear them so they run in their power band when pulling grades, but when we are running down the interstate I can still run in 6th gear at 2K rpm at 65 mph. My not sure about the other brands but Fords 6.2 with the 6 speed and 4.30 gears is a very capable pulling platform.

If you want to give your truck a test take hwy 191 south of 80 in Wyoming to Flaming Gorge Lake in Utah. On our last trip we were from sea level to 10K feet and it was a pleasure to drive.
The onlyh
Denny

So what gear and what speed are you running at say 5,000" pulling a hill with that rig.
Just wondering what the mileage is at, with those pulls.

Some just don't like the engine revving to 4,500 rpm, time to start pulling the feet back from the bell-housing.

I normally run it between 3200 and 4500 rpm on grades that need it, it will do 55 mph in 3rd no problem (and higher) on heavy grades. When we left our home base in Nebraska and headed west to Nevada by way of Utah to meet up with some rving friends before heading to Yuma by way of the North Rim of the Grand Canyon the truck averaged 8 but it was also still breaking in. After we came out of Mexico and headed to Texas and out of the big grades but still in the wind and rolling hills it averaged 9 by the time we got to the hill country. It took a while to figure out the power band and the manual shift mode on the transmission but after that it was fun to drive.

Denny
Colorado71
Explorer
Apr 25, 2014
I live at 10,000ft. Even though I'm only towing around 5,000lb I went with a turbo diesel. I hate driving NA engines up here, unless they are way, way over powered to begin with.
Blackcell
Explorer
Apr 25, 2014
Based on the weight & altitude you're in diesel country.
rhagfo
Explorer III
Apr 25, 2014
Denny & Jami wrote:
The trailer we are pulling last time I weighed it was 15901lbs and yes I pulling it with a gasser and just like all motors it has power lose at altitude. Newer gas motors adjust to the higher elevations on the fly unlike older models. But you can't run diesel gears in them, you have to gear them so they run in their power band when pulling grades, but when we are running down the interstate I can still run in 6th gear at 2K rpm at 65 mph. My not sure about the other brands but Fords 6.2 with the 6 speed and 4.30 gears is a very capable pulling platform.

If you want to give your truck a test take hwy 191 south of 80 in Wyoming to Flaming Gorge Lake in Utah. On our last trip we were from sea level to 10K feet and it was a pleasure to drive.

Denny

So what gear and what speed are you running at say 5,000" pulling a hill with that rig.
Just wondering what the mileage is at, with those pulls.

Some just don't like the engine revving to 4,500 rpm, time to start pulling the feet back from the bell-housing.
Denny___Jami
Explorer
Apr 25, 2014
The trailer we are pulling last time I weighed it was 15901lbs and yes I pulling it with a gasser and just like all motors it has power lose at altitude. Newer gas motors adjust to the higher elevations on the fly unlike older models. But you can't run diesel gears in them, you have to gear them so they run in their power band when pulling grades, but when we are running down the interstate I can still run in 6th gear at 2K rpm at 65 mph. My not sure about the other brands but Fords 6.2 with the 6 speed and 4.30 gears is a very capable pulling platform.

If you want to give your truck a test take hwy 191 south of 80 in Wyoming to Flaming Gorge Lake in Utah. On our last trip we were from sea level to 10K feet and it was a pleasure to drive.

Denny
Wiley75
Explorer
Apr 25, 2014
Agreed. It's all about air density. Turbocharging with aftercooling reverses some of the air density issues caused by altitude and high ambient temperatures. Problem is I'm not familiar with a 1 ton truck that features a turbocharged gasoline engine (yet). So for now I think a diesel would be the best choice for the OP.
wcjeep
Explorer
Apr 25, 2014
Look for a diesel with an exhaust brake and/or transmission brake assist. This keeps the vehicle service brakes cold for an emergency.

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