Gas or diesel?

As many have mentioned, the difference between the two types of engines as far as longevity is disappearing with the new regs and tech development. Someone else also mentioned a situation nearly identical to ours - IF and I mean IF diesel is available I've seen the prices fluctuate wildly. I've seen it as high as $1.65/gal more expensive than gas. So the diesel vs gas question is important to us.

Floorplans don't vary by much in Bs. There's only so many permutations of layout in that limited space. We like the twin beds because they can do triple duty as passenger seats and banquet seating with a table in between. Most of the time we're outside eating so the twins can be beds or passengers.

Trying to make a buying decision based on the cost of operation between diesel and gas is quite frankly futile. If you can compare the chassis and exact coach with the only variable the engine you may
get pretty close. Seems to me as two others have said the coach is important but so is the driveability and layout in the front since most B owners spend a lot of time driving. Most folks would benefit more by concentrating on their purchase price then worrying about thecost difference between gas and diesel!

FWIW - The new 4 cyl Mercedes Sprinter has essentially the same HP and torque as the old 5 cyl model.

The Sportsmobile website lists the mpg reported by their owners as:

Ford V-8 15 mpg
Ford V-10 12 mpg
Chevy V-8 14 mpg
Sprinter diesel in short body 22 mpg
Sprinter diesel in long body 20 mpg

I completely agree with Davydd's comment that the interior layout of the van is far more important than a couple of bucks +/- in fuel costs. B's have a limited amount of space and it is critical to get a layout that fits your particular needs.

booster wrote:
Here is a chart that shows the energy in the various fuels Diesel has a 13% advantage in energy per gallon. As the technology of direct injection gas gets better, and that the diesels now have to start meeting emissions, I think you will see the thermal efficiency of the gas/diesel question wind up very close together and the mileage difference very close to that 13%. The 25% difference in mileage number has been around a long time, before the recent changes.


Also remember that to be accurate in % better calcs, you have to be using similar power engines. Comparing an I5 Sprinter to a 6.0 Chevy or 6.8 Ford gasser is not a valid comparison as the gassers have much higher power. Plus the I5 Sprinters were generally hauling about 1000# less weight IIRC.

Not saying either is better, just saying be accurate in your comparisons.

Good valid points!

In my defense, not that you were reponding to my comment, I will add that I'm not a gear head, and get a headache when things get too mechanically technical. My comparison is based solely on my actual real life experience as an RVer.

Additionally, I'd like to say that both my 2003 PW Dodge and 2006 PW Sprinter were a both a pleasure to drive. I preferred the width of the 2003 (allowing the convenience of keeping my sideways oriented bed made); the abundant, for a B, amount of storage, utilitarian depth galley drawers and cabinets, the lower exterior height allowing easier access to the roof, its ground clearance, and butterfly side entry doors, inserts in front and rear for the removable support for the table; and the 45 degree turning capability of the driver seat.
But, I still enjoy the mpg of the Sprinter! :B

Here is a chart that shows the energy in the various fuels Diesel has a 13% advantage in energy per gallon. As the technology of direct injection gas gets better, and that the diesels now have to start meeting emissions, I think you will see the thermal efficiency of the gas/diesel question wind up very close together and the mileage difference very close to that 13%. The 25% difference in mileage number has been around a long time, before the recent changes.


Also remember that to be accurate in % better calcs, you have to be using similar power engines. Comparing an I5 Sprinter to a 6.0 Chevy or 6.8 Ford gasser is not a valid comparison as the gassers have much higher power. Plus the I5 Sprinters were generally hauling about 1000# less weight IIRC.

Not saying either is better, just saying be accurate in your comparisons.

We had a Forest River MB Cruiser Sprinter conversion for 8 years. Sold it last year prior to moving. It was not as elegant as most conversions, but served our needs at the time. We are currently looking for our next vehicle and thought we would end up with a gasser but are now leaning toward another Sprinter.

Observations on our first generation Sprinter:
Likes: We liked the mileage, how it drove, the openness inside with the large windows.
Dislikes: Lack of service options, especially trained experienced techs, availability of repair parts, propane generator combined with small propane tank, reliability of vehicle (3 major failures in 70K miles.

From the current crop of Bs we have looked at, the gassers seem more closed in and cramped, especially the Travato. Smaller windows, less headroom, less gas mileage. On the other hand, they were generally more affordable, gas genny, and more service options. Don't want to wait around for the Transit.

The Sprinters seem to have the openness and handling we like and most have larger propane tanks than we previously had. They are also expensive and have the service option problem but they have been out a while now and we are hoping the service tech and parts issues are better.

Before 2007 i would have said diesel is a big winner-after 2007 this answer get a lot murkier-.

Diesel does get better mileage than gas-but with these new emissions controls the difference is shrinking.

If you factor in up front costs-and the costs of having to get the dpf replaced or cleaned if you can about every 125,000 to 150,000 thousand miles this added expense seems to me to negate a diesels longevity advantage.

It's probably an overall break even between diesel/gas.

stan909 wrote:
Don't forget the new Mercedes 4cyl. It is supposed to get higher mpg comparable to the old inline 5's.Powertech makes a diesel genny that fits under the MB but it is costly.

Advanced RV built a 4 cylinder Sprinter B and drove it to Florida and Arizona on two separate trips from Ohio. I believe their real world mileage was 19.4 mpg. I don't know how using the heater and hot water which burned diesel or if they used the engine idle to charge the batteries factored in.

5 cylinder Class B Sprinters should average 22 mpg easy. I averaged 22.5 (actually 22.48) over 61,000 miles of accurately recording every fill. My 6 cylinder B is averaging about 18.4 mpg. I haven't kept as accurate of records with the 6 cylinder since there is a built in scan gauge to give me enough indication.

I go back to what I said earlier. If you have no problems with having either type of engine and you are paying a gazillion dollar premium for a B in the first place over some other type of RV then you should be more concerned about the other factors of design, layout and amenities since you are going to live in it. Besides, if you prefer the Sprinter designed Bs in general, then you have no choice.

Let me throw one more thing on the pile. Since I haven't used my van for almost 3 years, the fuel (diesel) is that old too. Diesel doesn't go bad sitting like that, gas does.

I'm not sure what the premium they are putting on diesels in the vans but with the pickups there is basically no way the fuel savings will ever cover the up front cost of the diesel unless you are driving commercially (ie: massive milage).

With the pickups, you can justify it based on towing a heavy load but with a class B, that is unlikely to be a justification.

It's nothing for modern gas engines to reach 250k miles so the longevity of diesels is no longer an issue.

The spreadsheet has it about right. For 120k miles, you may save $4k in fuel. If that is less it may make sense but diesel repairs are also somewhat higher and again we aren't in the old days. They need repairs about as often.