I presently own a 4000 pound 18 foot RV and pull it with a gasoline fueled, normally aspirated, truck rated to pull a 6000 pound trailer. However, when towing at 10,000 feet altitude, up a mountain, the truck will only make 30 MPH. I consider the truck grossly under powered and would purchase a more powerful tow vehicle if I was to replace the present truck. I would buy a gasoline, normally aspirated truck with a tow rating of TWICE my planned trailer GVWR to get good uphill, high altitude performance. Lesson is: The gasoline, normally aspirated tow vehicle's posted tow rating is not useful at high altitudes.I am planning to buy a new larger trailer, GVWR of 15,450 pounds. I am planning to buy a Dodge Ram 2500 Cummins turbo diesel truck to pull the trailer. What should be the published maximum towing capacity of the turbo diesel truck to get good performance at say 10,000 feet, uphill, or into a head wind at altitude?Does anyone out there have personal experience with a 2014 Dodge RAM 2500 Cummins diesel with a I am proposing a 2014 Ram 2500 Cummins with Exhaust Engine Brake, 6 speed auto transmission, 3.42 differential with rated tow capacity of 17,100 lbs. My trailer weight is 15,400 pounds. What is your opinion of the capability of the truck to pull at say 10,000 ft in the mountains?Does anyone out there have personal experience with a 2014 Dodge RAM 2500 Cummins diesel with a stock 3.42 differential pulling a 16,000 lbs. +/- trailer over 10,000ft. mountain passes?

Turbo engines, gas or diesel, barely lose power at elevation. The do generate more heat in the turbo at elevation, but the struck will be fine stock.

The type of fuel being burned has nothing to do with performance at elevation- it's the normal aspiration that causes the loss of performance. A Ford Ecoboost gas V6 will perform great at 10,000 feet while an older normally aspirated diesel will produce lots of black smoke and no power at that elevation.As to your question, it depends on what you consider good performance. 15,000 pounds up a steep grade at 10,000 feet elevation is not exactly easy criteria. Having said that, any of the new big 3 diesels will do just that with almost shocking performance levels- 19000 pounds in tow up a 7% grade at 60 mph. You also don't mention what year Dodge you plan to get. An old 12-valve at stock performance settings would be miserably slow, (although these are relatively cheap and easy to modify for more power) but a new truck would have all the power you need.

If your going to buy a 15K trailer, you need a one ton or your going to run out of payload.

Towing a 4k trailer in the mountains, you will be better off with a Ford Ecoboost or a Ram Truck 1500 Diesel. But, if you are looking at Ram Trucks (Or Older Dodges) for a 15k+ trailer, you should be looking at 3500 series of Ram Trucks.

ScottG wrote:If your going to buy a 15K trailer, you need a one ton or your going to run out of payload.What he said. The 2500 is only good for maybe 10 to 11k

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Colorado71
Explorer
Jul 04, 2014
I live at 10,000ft and have a 03' Cummins HO to tow a small trailer (3800lb unloaded and 5700 GVWR).

It will hold the speed limit over all the CO passes with smarty programmer on level 3.

Turbo's are like cheating at high elevation, I wouldn't own anything else. Unless it's grossly over powered to begin with (like my two stroke dirt bike).
powderman426
Explorer
Jul 04, 2014
rhagfo wrote:
ib516 wrote:
powderman426 wrote:
ScottG wrote:
If your going to buy a 15K trailer, you need a one ton or your going to run out of payload.

What he said. The 2500 is only good for maybe 10 to 11k

True, but also depends on the year. My 2500 has over 3000# payload, 5500# front GAWR, 6500# rear GAWR, and a 15,350# max tow rating. All of these capacities are higher than my previous Ram 3500 SRW.

With a 15,000 GVWR 5er you will still be out of payload with a 2500!!! Tow capacity is not PAYLOAD capacity!!

15,000 GVWR = 3,000# pin at 20% which is about average!

Exactly. Some people don't distinguish the difference between a fiver and a trailer.
Cummins12V98
Explorer III
Jul 04, 2014
gmw photos wrote:
I routinely pull 12K to 14K pounds ( horse trailer ) with our F350 dually. I am glad I got 4.10 gears.
My "personal opinion" ( so all you SRW fans, don't jump down my throat here ! ) is when going to a one ton, you might as well get Duals. If I need the capacity of a one ton, I might as well have the added stability of the DRW. There really is no other downside to it, other than a few more $$ to replace tires.

It won't fit in our garage, drive thru, car wash, can't park it, the list goes on for miles!
rhagfo
Explorer III
Jul 04, 2014
jfritz_drfritz wrote:
naturist wrote:

at 10,000 feet, non turbo engines will be down 20% or more in power, and that 20% comes off the top. That is, it takes the same toll on your power to run the alternator, pump the water, overcome engine friction; the power loss comes entirely off the part that moves you up the road, so is a great deal more noticeable than a MERE 20% might otherwise be

.

I guess I don't understand.
the alternator, water pump, internal engine friction are all parasitic losses and are the same at 0 ft elevation as they are at 10,000 ft elevation. As such they are constant in absolute terms i.e if they draw 40 hp at one elevation they do also draw 40 hp at another elevation. They do make up a larger percentage of the power the engine actually produces as the power drops off due to elevation rise, but since their draw is constant, they can be discounted in any discussion of engine power production related to elevation change. Manufacturer hp ratings are net ratings i.e. taken at the flywheel with a functioning water pump, power steering pump and alternator. So there is no "top" there is just your net hp and as you correctly state it drops off less with a turbocharged engine because the boost level stays constant at altitude (to a point).

You got part of it;
The parasitic HP requirements remain constant so if the parasitic draw on a 100 hp engine is 20 hp., you have 80 hp to move the load, or 100% of the remaining HP.
now at 10,000 ft. you loose 20% of HP (100 hp), so now you have 80 hp total for the parasitic draw and moving the load. 80-20=60, now you have 80/60=.75, so you have really lost 25 % of the power to move the load.
gmw_photos
Explorer
Jul 04, 2014
I routinely pull 12K to 14K pounds ( horse trailer ) with our F350 dually. I am glad I got 4.10 gears.
My "personal opinion" ( so all you SRW fans, don't jump down my throat here ! ) is when going to a one ton, you might as well get Duals. If I need the capacity of a one ton, I might as well have the added stability of the DRW. There really is no other downside to it, other than a few more $$ to replace tires.
blt2ski
Moderator
Jul 04, 2014
To me if you have say 100hp, you are at 10K ft. You will be down 2-3% or about 20-30%/HP. ie 70-80 vs 100 that you have at sealevel. That is the best way I can describe the % is off the top!

As far as the other items go.....not sure in my brain if they will take more hp per say to run or not....either way, a non turbo/super charged motor is down at elevation. THen comes the, how often are you up that high etc as to if you truly need to operate with a forced induction motor.

Marty
jfritz_drfritz
Explorer
Jul 04, 2014
naturist wrote:

at 10,000 feet, non turbo engines will be down 20% or more in power, and that 20% comes off the top. That is, it takes the same toll on your power to run the alternator, pump the water, overcome engine friction; the power loss comes entirely off the part that moves you up the road, so is a great deal more noticeable than a MERE 20% might otherwise be

.

I guess I don't understand.
the alternator, water pump, internal engine friction are all parasitic losses and are the same at 0 ft elevation as they are at 10,000 ft elevation. As such they are constant in absolute terms i.e if they draw 40 hp at one elevation they do also draw 40 hp at another elevation. They do make up a larger percentage of the power the engine actually produces as the power drops off due to elevation rise, but since their draw is constant, they can be discounted in any discussion of engine power production related to elevation change. Manufacturer hp ratings are net ratings i.e. taken at the flywheel with a functioning water pump, power steering pump and alternator. So there is no "top" there is just your net hp and as you correctly state it drops off less with a turbocharged engine because the boost level stays constant at altitude (to a point).
rhagfo
Explorer III
Jul 03, 2014
ib516 wrote:
powderman426 wrote:
ScottG wrote:
If your going to buy a 15K trailer, you need a one ton or your going to run out of payload.

What he said. The 2500 is only good for maybe 10 to 11k

True, but also depends on the year. My 2500 has over 3000# payload, 5500# front GAWR, 6500# rear GAWR, and a 15,350# max tow rating. All of these capacities are higher than my previous Ram 3500 SRW.

With a 15,000 GVWR 5er you will still be out of payload with a 2500!!! Tow capacity is not PAYLOAD capacity!!

15,000 GVWR = 3,000# pin at 20% which is about average!
valhalla360
Navigator
Jul 03, 2014
Out of curiosity, what are you towing with?

Unless you are up at 10k regularly, it's probably just fine if it's rated as you suggest and the vehicle is in good running condition.

If you will be up above 6k regularly, a forced induction (turbo) engine can be a nice addition to compensate for altitude.
ib516
Explorer II
Jul 03, 2014
Redsky wrote:
Going with the 3.42 gears will be a big mistake. Get the 3.73 gears and the engine will be better able to operate at its peak torque portion of the power band. No sense in getting a diesel engine and then handicapping it for towing with tall gears.

Check the towing specs for the truck with the different gear ratios. 3.73 provide a 25% increase over 3.42 gears for the same truck with the same engine. When towing the taller gears are more likely to hurt than help fuel economy.

All you can get without dual rear wheels is 3.42 in the new diesel Rams (2014+). If you get the Hemi, you get a choice of 3.73 or 4.10.

A 2500 Ram/Cummins 3.42 is rated for over 17,000# max trailer.