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Discussion Starter #1
I'm considering a PM to use as a toyhauler (seating for 5 + bikes in the back) and to tow our 3500# camper (probably close to 4000# on the road). I realize this is likely close to the max capacity of a 2500 (say 2000# IN the PM with bikes and passengers + gear). The diesel would be the smart choice, but with fuel prices and the $4000 tax, I think I'd rather have the gas engine.

Has anyone towed anything substantial with their PM with also a load in the van? I'm curious how it felt and how the mileage played out. I suspect the towing MPG is lousy on the gasser (~10 MPG I'd guess).

Any experience yet? 3000 or so of these vans have now been sold. Someone must have towed with it by now.
 

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I hooked up to our 5400 lb trailer and had 1800 lbs of salt on a pallet through the side door. Went through lots of heavy wet snow with no problem at all. Even pulled into a parking lot that hadn't been plowed. Stopped, accelerated, braked, turned all with no problem in about 6 inches of the slippery white stuff.
It did seem to rev pretty high before shifting, though. At part throttle, it wouldn't shift until over 6,000 rpm. It didn't feel like it was struggling at all, just seemed like it should've shifted sooner.
 

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I hooked up to our 5400 lb trailer and had 1800 lbs of salt on a pallet through the side door. Went through lots of heavy wet snow with no problem at all. Even pulled into a parking lot that hadn't been plowed. Stopped, accelerated, braked, turned all with no problem in about 6 inches of the slippery white stuff.
It did seem to rev pretty high before shifting, though. At part throttle, it wouldn't shift until over 6,000 rpm. It didn't feel like it was struggling at all, just seemed like it should've shifted sooner.
Impressive! You were probably loaded above gross combined weight rating.

As to high RPM before shifting up, it's probably needed due to engine's high-RPM nature and transmission wide ratio steps. 6000 RPM is near engine maximum power, and when it shifts up the RPMs would drop to "around" 4000 RPMs, which is close to maximum torque. This decreases chance engine would bog down after shifting up.

If it shifted up at 4000 RPM (near max torque) and RPM dropped to around 2500, the engine may not be able to pull the load and could bog down, causing it to downshift back to the gear it was in previously. And if it did this repeatedly, the "gear hunting" would drive the driver nuts.

Fortunately, if power train is programmed properly, the computer knows in advance if the next gear is viable or not. The computer can estimate how much power is being produced and whether the engine can produce it at the lower RPM associated with the next shift. If the van was less loaded it would be able to shift up at lower RPM because the next gear would not bog down the engine.
 

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Discussion Starter #4
MChrist - Thanks for the response. Did you do any highway driving? What about going up hills on the highway at 65-70 mph? I'm really curious how that engine performs with a load.

I'll also be very curious to hear MPG reports for people towing.
 

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I hooked up to our 5400 lb trailer and had 1800 lbs of salt on a pallet through the side door. Went through lots of heavy wet snow with no problem at all. Even pulled into a parking lot that hadn't been plowed. Stopped, accelerated, braked, turned all with no problem in about 6 inches of the slippery white stuff.
It did seem to rev pretty high before shifting, though. At part throttle, it wouldn't shift until over 6,000 rpm. It didn't feel like it was struggling at all, just seemed like it should've shifted sooner.
My guess is they might have it set to shift at 6k for overall better performance?
 

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Don't have my van yet but I've been on a trip to Florida and back in a Ford Expedition with a big box trailer full of motorcycles in tow. It wouldn't pull overdrive and it used 22 - 23 L/100 km at 100 km/h ... Fuel consumption is never going to be good with a big parachute behind. I would imagine that the Pentastar + 6-speed auto will beat the Ford 5.4 + 4-speed auto, though ...
 

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.....cut......
I suspect the towing MPG is lousy on the gasser (~10 MPG I'd guess).
Results should largely depend on what size trailer you will be towing, and whether you are talking city or highway MPG. Based on my experience (with various tow vehicles not a PM) dropping to 10 MPG or even lower is very possible depending on trailer size and weight. And also on how fast you drive on highway since wind drag goes up quickly with speed.

I highly recommend that when you receive feedback that you consider trailer size and not just weight. Also, it may sound counterintuitive, but in my opinion starting out with a fuel-efficient tow vehicle like a ProMaster will lead to a greater drop in fuel economy when towing (if measured as a percent). I’ve towed many trailers with different size tow vehicles (from a V10 motorhome to 4-cylinder pickups) on long road trips over the years and the data is fairly predictable. They were not for a PM but if interested I can share examples to show general trends.
 

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Discussion Starter #8
Certainly good points. I'm thinking about highway mpg. I have a 21ft travel trailer (7ft wide and 9 ft tall). With my 06 E350 5.4 I get a consistent 15.5 mpg with the van loaded but no trailer, and right around 10.5 mpg on the highway at 70 mph.

I'd be willing to bet that the same setup with the PM would yield about the same MPG in my case. However, the experience might be less desirable. The 5.4 never really even groans. I'm thinking on the big hills (I live out west) the PM gasser will be screaming :)
 

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fuzzy, that's consistent with my expiriences as well. I towed a small camper trailer of equal size from Texas to Florida and back with an F-150 pickup with small 4.6L V8 and only got 11 MPG by driving between 60 and 65 MPH. It was light at around 2500 pounds but like Brian P stated above it acted like a parachute.

On the plus side a PM is wider and taller than most pickups and US vans, so it should serve as a little better fairing to reduce wind drag on trailer. When I towed a small 4000 pound trailer behind an RV I owned the mileage only dropped from 8 MPG to something over 7 MPG. There wasn't much difference in fuel consumption because the trailer was smaller than the RV, so wind drag wasn't too bad. On the other hand the same size trailer behind a 4-cylinder truck dropped my mileage from 25 MPG hightway to just under 15 MPG, and it was that good only because I had to drive slowly.

I'm interested in a PM for a Class B RV, and would also tow a small camping trailer (about same size as yours) occassionally for longer trips and or when camping with family. Since Class Bs can be heavy, my biggest concern based on specs is whether the van can safely handle the extra weight.

By the way, one thing I haven't found on PM specs yet is whether there is a trailer size limit. Many smaller vehicles are often limited to 50 square feet of trailer frontal area and sometimes even less.
 

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The Promaster has an awesome CX of 0,31. This is an important value when you are towing. Also the shape and the distance of the trailer is fundamental.
I think it will do better than many other vehicles, especially in the high roof configuration.
 

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By the way, one thing I haven't found on PM specs yet is whether there is a trailer size limit. Many smaller vehicles are often limited to 50 square feet of trailer frontal area and sometimes even less.
Per the owner's manual (Pg. 261, version 3):

Low Roof trailer frontal limit = 45.3 Sg. ft.

High Roof trailer frontal limit = 51.7 sq. ft.
 

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Per the owner's manual (Pg. 261, version 3):

Low Roof trailer frontal limit = 45.3 Sg. ft.

High Roof trailer frontal limit = 51.7 sq. ft.
Thanks much; that's very important data. And unfortunately very disappointing as well.

Sounds like trailer frontal area must be very close to PM's frontal area (an estimate on my part). That pretty much eliminates all camping trailers except those that fold down.
 

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Thanks much; that's very important data. And unfortunately very disappointing as well.

Sounds like trailer frontal area must be very close to PM's frontal area (an estimate on my part). That pretty much eliminates all camping trailers except those that fold down.
I sometimes tow a cargo trailer (6' X 8.75' = 52.5 sq. ft.) with an F-150 Pickup. It is rated for 60 sq. ft. frontal area if equipped with the trailer tow package (includes upgraded transmission cooler) and rated at the frontal area of the truck without the trailer tow package.

I believe that the Promaster Tow Package is currently unavailable. If it becomes available, I was hoping that the frontal area rating would also increase if equipped with the tow package. From what I can tell, the PM tow package only includes the hitch and wiring and no transmission cooling upgrades. So there will probably be no increase to the frontal area rating and my cargo trailer is slightly over the limit for a tall roof PM.
 

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tgblake, does the owner's manual differentiate between gasoline and diesel engines as far as towing goes? Does the OM even address the diesel?
 

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tgblake, does the owner's manual differentiate between gasoline and diesel engines as far as towing goes? Does the OM even address the diesel?
The chart I was using on page 261 of the OM referred to the gas engine. It did not address the diesel. However there is a supplemental OM for the diesel. There is a similar towing chart on page 73 of the diesel supplement and the frontal area limits are the same.

Here are links to version 3 of the owners manual and for the diesel supplement OM.


Owners Manual:
http://www.ramtrucks.com/download/pdf/manuals/2014-RAM_ProMaster-OM-3rd.pdf

Diesel Supplement to owners manual:
http://www.ramtrucks.com/download/pd...sel-SU-1st.pdf
 

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Can you explain what this means?
Thanks.
It means that with this Cd and van's frontal area, we can estimate how much power it takes to drive the van at any given speed and air temperature with fairly good accuracy.

The only significant guess we would need to make is for the coefficient of rolling resistance, and fortunately that's a relatively small contributor at highway speeds. So even if we guessed slightly off it wouldn't make a big difference.
 

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Discussion Starter #19
The manual shows the MAX tongue weight to be 220 pounds! Even though they recommend the tongue weight be 10% of the trailer weight and the max trailer weight is 5100 pounds. This doesn't really make any sense. Anyone reading this information differently?

Max.
Tongue
Weight
220 lbs
(100 kg)
Van
510 lbs
(231 kg)
Chassis
Cab /
Cut
Away
 

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The manual shows the MAX tongue weight to be 220 pounds! Even though they recommend the tongue weight be 10% of the trailer weight and the max trailer weight is 5100 pounds. This doesn't really make any sense. Anyone reading this information differently?

Max.
Tongue
Weight
220 lbs
(100 kg)
Van
510 lbs
(231 kg)
Chassis
Cab /
Cut
Away
I have seen other sources that say Max Tongue Wt is 510# with a dead weight hitch and 765# with a Weight Distributing hitch (10% and 15%, respectively, of the max trailer weight of 5100#) 510# is listed for the Chassis Cab/Cut Away in the owners manual. I am not sure why the Van would be that much lower. I am guessing that the 220# is not correct, but that should be confirmed.
 
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