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So how is the fuel consumption for those of you driving heavily loaded Promasters? I have a 7x12 enclosed trailer that typically weighs in around 3000lbs and will be carrying around 1000 additional pounds of gear in my van. My driving is a 50/50 mix of highway and city and I'm rarely in a hurry. Any idea on what type of MPG's I can expect with a high roof 159" Promaster with this load? Gas? Diesel?

I'm currently driving a gas Ford E-350 and consistently get 13 mpg without the trailer and about 11 with it. Power is no problem with the Ford, but I'd be ok with sacrificing a little power with the smaller displacement V6 if it means smaller fuel bills. I'm still leery about the diesel with the engine light and limp mode horror stories, but those seem to have died down a bit so maybe FCA is finally on the ball.
 

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Adrian an owner from earlier (since bought a truck to get higher towing limits) had that sort of setup and reported about 23mpg IIRC on trips to his son's racing venues with his 159 Diesel all highway I believe. I always marveled at his mileage and would have been expecting 20.

Here are some of his quotes:
"Trailer loaded and connected to Van. Total weight 8,800lbs Van and trailer checked on scales. Will be leaving in about 5 hours at Noon Chicago time, 890 mile trip to Dublin Georgia."

"The van is awesome! Leaving Chicago , first 35 miles light traffic leaving Chicago. Afterwards it rained the entire time until I stopped for fuel. Heavy rain at times and lots of wind , side and head wind. Very hilly. This van is amazing on highway, 8,800 lbs with the additional drag of the trailer. The van never downshifted, not even once. You can even accelerate going up hill. I left it in drive on the highway the entire time.
473 miles / 22.35 gallons of diesel = 21.16mpg. Not ideal scenario for good mpg in those conditions. This van will better that mileage in better conditions easily. Very happy !!!"

"Early stop bathroom break.
227 miles 9.53 gallons equals 23.1 mpg
Diesel cost in Tennessee $ 3.16 per gallon."

"Final fill up netted an average of 21.8 mpg for the last tank of diesel! For the entire trip the van averaged 22.1 mpg.

Some of the things I've learned from having the gas PM and now the Diesel.

The Diesel is a highway king! Unless you are looking at the Instant mpg display you can not tell if there is a direct head wind or a hill. The van felt absolutely effortless towing. Thru Chattanooga Mountains I slowed to 55mph, I could have maintained a higher speed easily but with mpg's in mind I slowed. In Drive the trans was holding sixth and pulling it easily. If I didnt know the power rating of this diesel and had to guess i would think it has over 400 lbs ft of torque. The guys and gals that currently have the diesel PM understand. The van does not feel a load. I purposely stepped on the gas pedal harder during the mountain climb to get the down shift to 5th. I just felt like i didnt need to put so much load on the bottom end of a new motor when a few extra rpms will make it easier for the bottom end to go up the mountain. Also, 5th gear seems closer spaced to 6th gear compared to the gas PM. The new diesel 159 van is 700 lbs heavier than the gas 136 I replaced. I am very happy with the van.

With the gas PM towing the same trailer I would average 16-18 mpg. Creatively i can keep the downshifts to a minnimum by avoiding the cruise control and only using the cruise to rest my foot every now and than. I would speed up going down hill and slow going up hill. This would minimize the downshifts drastically while towing. The only thing i couldn't avoid in the gas PM was when there was a headwind and at that point it typically just stayed in 5th gear. With the diesel non of that, cruise the whole time and speed never fluctuated. That made it easier to drive and less fatiguing.

In todays difference in Diesel to Gasoline prices during this 2000 mile round trip, it would have cost less in the Gas PM. Most everywhere the difference in gas to diesel was $1.00 per gallon.

Gas fuel cost - 2000 miles / 17mpg =117.64 gallons x $2.45 =$288.23
Diesel fuel cost -2000miles/ 22mpg = 90.90 gallons x $3.45 = $313.63

To tow a trailer and get this type of fuel mileage is absolutely amazing! Ask any guy with a pick up truck that tows even a empty enclosed 7 foot tall trailer and due to drag they will get 10-11 mpg. The tall PM is great for towing in eliminating all aero drag except for the additional tires on the ground.

I will predict this diesel engine will be a very high mileage capable engine!"

I hope this helps.
 

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I have a 159 gas and I can honestly say that you won't be happy with the gas. It just doesn't have the torque. I live in FL, and when on the highway and going into a good head wind, it struggles to stay in top gear. That's on flat road and just a little cargo.
 

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136 low top just got 16.2 pulling a 3000 lb bassboat on a hundred mile round trip, about 75% highway. Usually get right around 19 not towing. I am happy with it!
 

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136 low top just got 16.2 pulling a 3000 lb bassboat on a hundred mile round trip, about 75% highway. Usually get right around 19 not towing. I am happy with it!
Gasser??
 

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....cut....

Gas fuel cost - 2000 miles / 17mpg =117.64 gallons x $2.45 =$288.23
Diesel fuel cost -2000miles/ 22mpg = 90.90 gallons x $3.45 = $313.63

....cut.....
His 22 MPG diesel versus 17 MPG gasoline (30% higher) is right in middle of Cummins' rough estimate of 20 to 40 percent better for diesel versus gasoline when performance is close to equal.
 

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So how is the fuel consumption for those of you driving heavily loaded Promasters? I have a 7x12 enclosed trailer that typically weighs in around 3000lbs and will be carrying around 1000 additional pounds of gear in my van. My driving is a 50/50 mix of highway and city and I'm rarely in a hurry. Any idea on what type of MPG's I can expect with a high roof 159" Promaster with this load? Gas? Diesel?

I'm currently driving a gas Ford E-350 and consistently get 13 mpg without the trailer and about 11 with it. Power is no problem with the Ford, but I'd be ok with sacrificing a little power with the smaller displacement V6 if it means smaller fuel bills. I'm still leery about the diesel with the engine light and limp mode horror stories, but those seem to have died down a bit so maybe FCA is finally on the ball.
Do you have the 5.4L V8 or 6.8L V10? Or is it pre-1997? You can extrapolate from your present van's MPG, but knowing engine size and even final drive ratio will help you get closer.
 

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My 136/low roof gas engine used about 14 L/100 km (16.8 mpg US) while towing a 5x10 enclosed trailer with about a tonne of additional load split between the van and the trailer, mostly highway. It does go between 5th and 6th gear a lot. If you are planning to do a lot of towing and you want a bigger configuration of the vehicle, go with the diesel engine. I know there have been a few reports of glitches but these are never as common as internet forums make them seem.

I didn't opt for the diesel because I only tow occasionally and the van isn't a daily driver, so it wasn't worth the extra cost. With nothing in tow mine uses 11-ish L/100 km which I am OK with.
 

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I think the trailers' aerodynamics has to be considered as much if not more than the total weight.

I pulled +/- 4,000-pound trailers a couple of times with 4-cylinder pickup trucks, yet couldn't pull a 2,000-pound travel trailer at all because I couldn't get up to highway speed. The heavier trailers were 6X12 and fairly low, while the camper was 7-feet wide and close to 10-feet tall. I then switched to pickup with small V8 and only got 11 MPG highway even though it only weighed 2,000 pounds. In this case the trailer weight wasn't what required a lot of horsepower.

A gasoline PM no doubt has a lot more power, but not at 2,000 RPMs, so it's possible it may not be able to hold 6th gear very often. Final gear ratio may make a significant difference also.
 

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Yes; the 5x10 trailer was fully within the frontal area of the van, which should help.

On a previous trip we used an open trailer that was about the same size but with two motorcycles tied to it in the open. The consumption was about the same. An open trailer with that kind of load is aerodynamically very dirty.
 

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Yes; the 5x10 trailer was fully within the frontal area of the van, which should help.

On a previous trip we used an open trailer that was about the same size but with two motorcycles tied to it in the open. The consumption was about the same. An open trailer with that kind of load is aerodynamically very dirty.
True, but define "dirty".

An open trailer with two motorcycles would have a high coefficient of drag if tested alone in a wind tunnel, but when it's tucked behind a larger van it mostly drafts the van. In that case what matters most is how much does it add to the combined van-plus-trailer drag force. My guess is that when small trailers are behind a large van, their shape or individual Cd (as tested alone) would make much less difference. An example is that when I towed my 3,500-pound Ranger behind my E-350 van it didn't affect highway mileage hardly at all.

Also the fuel consumption of the van towing the pickup was much less than if both were being driven separately. In my opinion weight during highway driving on level roads has very little impact on required power or fuel economy.
 

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I have a 136 high roof diesel 2500 that got about 27mpg when it was an empty cargo. That was highway with some city. It weighed about 5200lbs. It has been converted to a camper van and now weighs 7400lbs with water, fuel and me. I get about 23.5mpg now. This past week I was in eastern NC towing a motorcycle trailer weighing 1000lbs and my mileage dropped to about 23mpg.
 

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I have a '14 gasser hi roof 136" I bought new last Sept. Just 7600 miles on it now. Lightly loaded on road trips it will get 21-22 mpg at 65-70 mph. I don't drive faster than 70 mph. Just my personal speed limit. I find the van very comfortable. I haven't needed to tow my enclosed single axle 6 x 10' cargo trailer yet, but it always pulled well behind my old van. I doubt the PM will have issues with it.
 

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I have a 2016 159" high roof gas and with my minor camper conversion wife 2 kids and our gear I was getting 23mpg all highway staying 65mph or under if you start getting over 65 it will drop. around town in the hills of southwest PA I see 15-16 but if I'm heavy on the foot it gets down close to 14 mpg. I have a travel trailer and haven't really towed it yet so I cant report on that. with my 400Lb alum. trailer and 1000lbs side by side I get about 17 MPG on 2hr trip to camp which is about 65% highway and I keep it at or below 65mph.


I don't think you will like the towing power of the gas as others have said. For what I got it for and that was a small camper conversion (sleeping for 4 seats, overhead cabinets, floor ,insulation, extra battery and power panel) it has been great and getting better than 20MPG on the highway is all I could hope for. my travel trailer is around 4200Lbs loaded and once I get the stronger hitch put on ill get to tow it this summer and use it local and see how the van does.
 

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I have a 3500, high roof extended gas. Towed VW Jetta on U-Haul tow dolly back from the purchase of said 2015 PM van from Huntsville AL to Knoxville TN. Approximately 3000 LBS towed, nothing in van. Dash said I averaged 14.3 but fuel fill said 13.4mpg. kept the the speedimit of 55 or 65. May have hit 70 on the cew flats. Almost all rolling hills. It accelerated and stopped better than my 97 Suburban 350 vortex towing the same weight. Suburban would get 11-12mpg. Without trailer and lightly loaded it has been getting 16-17mpg. The 3500 does have a lower final drive than the 2500. I never noticed a problem on hills. I did run it in tow mode and tried it with tow mode off a little bit. In tow mode it seemed to stay in 6th a little longer and didn't seem to flair or smooth the shifts so maybe it keeps the torque converter locked a bit more. Not 100% sure. Yes it did seem to down shift to 5th fairly often. It was easier to tell in the suburban when the torque converter came out of lockup and I would then downshift to 3rd to keep heat out of the trans, so the suburban would also downshift to 3rd a bunch.

It would have cost me at least $10k more to get a diesel with the same options. I do prefer driving the torque of a diesel. The 3500 gas definitely does accelerate nice. Call me torn between the 2.
 

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Doesn't anyone lock the gasser transmission in 5th while towing (straight 1.0 ratio)? I have a 97 Dodge Cummins that I use to pull a 29 ft fifth wheel and always pull in 3rd, no OD. I do this to protect the engine and transmission. I am considering a Promaster gas 2500 as the diesel option costs too much. If I was towing, I would use 5th gear.
 
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