Is diesel dead?

[gregmchugh]

Originally Posted by Roadtrek Adventuous RS1

https://www.mercedeshoffman.com/abou...inter-history/

Since 2010 Mercedes Benz is again exclusively selling the Sprinter...no more affiliated with Dodge..

Whether it's a Dodge or Mercedes.... there's a lot of history to the commercial vehicle market and the Sprinter is no exception... it's certainly one of the roomiest vehicles out there for conversions.

The diesel application in the vehicle for an 11,000 plus, one ton truck is really amazing.
I tell people to purchase one used... it's crazy to get one new... solid base engine....

Freightliner still sells Sprinters under there own brand and while only a few of the Freightliner dealers handle the Sprinter, they are a very good location for service since they tend to have lower prices for service and genuine parts than you get at the Mercedes dealers. Donuts and coffee in the waiting room instead of pastries and espresso with a less elite set of customers usually fleets or tradesmen...

[Davydd]

My nearest Freightliner dealer has Lay-Z-boy loungers in the waiting room.

[gregmchugh]

Originally Posted by Davydd

My nearest Freightliner dealer has Lay-Z-boy loungers in the waiting room.

You usually find a few truckers sleeping in the waiting room at a Freightliner dealer waiting for their semi trucks to get serviced. I had our Sprinter in the dealer in Tampa last week and got to hear the life stories of a couple of truckers in for service...

Our Freightliner Sprinter dealer in Michigan only sells Sprinters and Thomas School Buses so we don’t get the semi truck drivers in there, only tradesmen and school bus drivers...

[avanti]

Freightliner is probably statistically cheaper than MB on service, but I have encountered significant exceptions, so best to call ahead.

OTOH, one BIG advantage of Freightliner is that they often have a "no appointment/first-come-first-served" model, which can be a big advantage when you have an issue when on the road. Get up early and you can be in-and-out.

[avanti]

Originally Posted by gregmchugh

Our Freightliner Sprinter dealer in Michigan only sells Sprinters and Thomas School Buses so we don’t get the semi truck drivers in there, only tradesmen and school bus drivers...

Does that happen to be Hoekstra’s in Grand Rapids?
They helped us out during a "limp-home" emissions crisis. They are the best.

[gregmchugh]

Originally Posted by avanti

Does that happen to be Hoekstra’s in Grand Rapids?
They helped us out during a "limp-home" emissions crisis. They are the best.

Yes, two Michigan locations in Grand Rapids and in Troy, a northern suburb of Detroit, where we have our RT Freightliner Sprinter serviced. Expert techs with experience from before any other dealers sold Sprinters in the US. Great prices on service and parts. They are the best Sprinter service locations that I ever found.

[Boxster1971]

Originally Posted by gregmchugh

You usually find a few truckers sleeping in the waiting room at a Freightliner dealer waiting for their semi trucks to get serviced. I had our Sprinter in the dealer in Tampa last week and got to hear the life stories of a couple of truckers in for service...



Our Freightliner Sprinter dealer in Michigan only sells Sprinters and Thomas School Buses so we don’t get the semi truck drivers in there, only tradesmen and school bus drivers...

The Freightliner Sprinter dealer in Annapolis, where I get mine serviced is also a bus dealer. I seldom see anyone waiting the few times I've waited. They service a lot of Sprinters from all over the Wash D.C. area. Just bad coffee and a vending machine in the lounge, which is also the employee lounge. But they have a couple of Lazy-Boy recliners and a lunch table with chairs. Freightliner has been selling Sprinters in USA since 2001. A few skilled Sprinter mechanics I've met in the past at a MB dealer came from Freightliner Sprinter dealers.


- - Mike
2012 Sprinter 3500 Extended converted B-Van by Airstream

[mlts22]

The Freightliner dealer in Austin is excellent. So is the Georgetown Mercedes place. Of all places to have a Sprinter, where I live is probably one of the best outside of Germany.

[BBQ]

https://www.youtube.com/watch?v=D6YmAecTolQ

[Mfturner]

Nice video. I know engine designers have been working on #2 for several decades with clever chamber design, but at some level it probably persists. And the bottom and stroke and turbo arguments are really design decisions. But an interesting video.

[booster]

Originally Posted by Mfturner

Nice video. I know engine designers have been working on #2 for several decades with clever chamber design, but at some level it probably persists. And the bottom and stroke and turbo arguments are really design decisions. But an interesting video.

Yep, the cylinder head, piston top designs have changed a lot over the years from the old styles we saw in the 60s and 70s. High turbulence and high intake velocity help a lot with a heavy emphasis on distribution. All you have to do is watch your Scangauge instantaneous timing display to see how different they are. It used to be the regular fuel engines would run into the low 50 degree range of advance under light load and cruise and now it is rare to see them even flash up to 40 degrees for an instant. Our Chevy van at highway speed is normally running in the mid 30s for timing.


The discussion of bore and stroke was a bit incomplete, I think. I can't speak for diesel, but for gas engines there are sweet spots for displacement, bore size, etc that are relatively constant. That is part of the reason you see a lot of around 3.5L six cylinder engines and around 2.6L four cylinders (they have the same liters per cylinder). The 4.6L V8 is also the same per cylinder. Gas engines also have the same general trait of higher torque engines will have longer strokes in relation to their bores than shorter strokes. Short stroke engines will have less torque but be capable of higher rpm so often make more horsepower than long stroke engines. I don't think that this sort of geometry stuff is an advantage for either style engine.


What I don't think was mentioned is that diesel fuel contains more heat energy, so will make more power if you supply enough air to it, per gallon. Diesels are direct injection and run with 100% air charge essentially all the time, so they are more likely to have all the fuel reaching enough oxygen in the chamber. This is an area where the direct injection gas engines have significantly closed the efficiency gap with the diesels.


Another big equalizer is using the turbos on the gas engines, as it levels the playing field in terms of available air. Gas engine turbos are a little tougher to size because they need to cover a wider rpm range with it's much larger airflow variations, but the new designs are getting much better. Turbos also allow the manufacturers to design the same style low rpm, long stroke, high torque, style engines that they do for diesel.

[Roadtrek Adventuous RS1]

Originally Posted by Mfturner

Nice video. I know engine designers have been working on #2 for several decades with clever chamber design, but at some level it probably persists. And the bottom and stroke and turbo arguments are really design decisions. But an interesting video.

This guy is very smart.... knows exactly what he's talking about... very impressive...

Overall, I'm extremely happy I purchased my diesel.... very efficient..18 to 19 MPG consistently...and it's fairly quiet ...

[Mfturner]

Regarding the fuel's energy density, ethanol penalizes gasoline at half it's energy density, which is why it has never taken off as a long distance backpacking cooking fuel in the USA despite needing almost nothing to burn it, you have to carry twice as much of the fuel by weight as you might butane or white gas for a long trip. I wonder if biodiesel has a similar penalty? I have no idea.

[avanti]

He is the same guy who did the video on how we can prove that modern oil can last 20,000 miles. Well worth watching:

https://www.youtube.com/watch?v=l-zDt9FGJi8

I like him a lot. I think I will see what else he has done.

[avanti]

Originally Posted by booster

Another big equalizer is using the turbos on the gas engines, as it levels the playing field in terms of available air. Gas engine turbos are a little tougher to size because they need to cover a wider rpm range with it's much larger airflow variations, but the new designs are getting much better. Turbos also allow the manufacturers to design the same style low rpm, long stroke, high torque, style engines that they do for diesel.

Generally speaking, modern gas engines are being designed much more like diesels, with sophisticated, powerful designed-in turbos, direct injection, etc. Combine that with many-gear transmissions, variable displacement and fancy controls and many of the differences described in the video are becoming much less relevant.

[Roadtrek Adventuous RS1]

Originally Posted by avanti

Generally speaking, modern gas engines are being designed much more like diesels, with sophisticated, powerful designed-in turbos, direct injection, etc. Combine that with many-gear transmissions, variable displacement and fancy controls and many of the differences described in the video are becoming much less relevant.

I agree with you that gasoline engines have come a long way... back in the 60s.. people used to make fun of guys with smaller V8s... and if you had a FOUR or SIX cylinder.. they would laugh.. they're not laughing anymore about FOUR cylinder cars... for example.. the Subaru WRX STI has 305 HP... and 290 foot pounds of torque...

In the world of RVs.. it's all about torque.. these things way a lot... and you don't need to have excessive acceleration, they aren't race cars..

Don't know about you, but, I'm concerned about fuel efficiency.. over the lifetime of vehicle ownership, fuel is the most expensive thing you put in any vehicle...

The main reason I chose a diesel engine and Mercedes Benz has been making and selling diesels continuously since 1936..( although not in the USA)... was that I wanted an engine with great reliability and could easily climb mountains ...

I've been in plenty of gas vehicles that could certainly climb up steep grades, but, the engine RPMs were very high and it had to work a lot harder...

The diesel engine generates peak power at a much lower RPM.... around 2,500 to 3,000...

I'm very pleased with the solid 18 to 19 MPG... and I have a very heavy rig with the dual wheels....

[booster]

Someone on here mentioned, quite a while ago, that their V6 Sprinter climbed at about 3500rpm IIRC. It may have been davydd, but I am sure others would know also. I was surprised at it was that high.

[Davydd]

Originally Posted by booster

Someone on here mentioned, quite a while ago, that their V6 Sprinter climbed at about 3500rpm IIRC. It may have been davydd, but I am sure others would know also. I was surprised at it was that high.

Nah! I’m not that knowledgeable. I did marvel once where I drove a Subaru Turbo gas engine Outback in the Rocky Mountains. That’s when I realized they were popular out there and not solely for AWD.

[Roadtrek Adventuous RS1]

Originally Posted by booster

Someone on here mentioned, quite a while ago, that their V6 Sprinter climbed at about 3500rpm IIRC. It may have been davydd, but I am sure others would know also. I was surprised at it was that high.

https://www.edmunds.com/mercedes-ben...eatures-specs/

OK, my owner's manual says 190 HP and 325 foot pounds of torque... this says 188... I wouldn't quibble with someone over two horsepower.... it's the torque I'm concerned with.

325 foot pounds of torque at 1,400 RPM... remember I said that the lower the RPM, the better..

and maximum horsepower at 3,800 RPM.... redline

I just let the 5g tiptronic transmission shift up automatically, it always knows where it's supposed to be.

This is a turbo diesel double overhead cam, 24 valves engine with 18 to 1 compression.

For such a large and heavy vehicle like the Sprinter, she moves out pretty good. I think the zero to 60 is around 11 or 12 seconds. Again, for a vehicle this size, that's very respectable.

I've never been in any situation where it wouldn't climb up hills easily, normally doesn't even shift down, occasionally it does, when I climbed up the Eisenhower pass at 11,000 feet..

I can assure you that my gasoline Subaru Outback with a redline around 5,500... would not go much faster up hill especially.

Subaru's are extremely fast at top end... I think my 2.5 is rated over 120 MPH, and the 3.6 is supposed to be able to reach over 140 MPH...
WHO on earth needs to go that fast in any vehicle let alone an RV...

Fastest I've been in my RV for a brief period of time was 80....supposed to have a speed governor at 83 or 85..

The Sprinter can easily cruise all day at 75... again, not what I normally do... Normally, I'll drive no faster than 65... gets better mileage that way.

[Mfturner]

I've been on steep enough grades that the v6 diesel rpm was in the mid 3000's to climb, so I can believe someone claiming 3800. The Winnebago Trend (Promaster) we rented was in the mid 5000's on similar hills. Riding in a van for an extended climb in the mid 5000's is unpleasant, not to mention 8 mpg.