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Old 01-24-2021, 07:57 PM   #81 (permalink)
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The small diesels get superior fuel mileage, just as the large diesels do, in their respective categories relative to comparable gasoline vehicles. It's no surprise, given the relative energy content per gallon of the two types of fuel.

The question is, what are the comparative overall, long-term economies, especially after the warranties are gone? These economic factors include not only the comparative cost of fuel and engine fuel-usage rates, but also all the other costs involved in running the machines.

I think the issue is yet to be determined over the long term, given the complexity of environmental rules and the design of diesel engines needed to meet them.

Otherwise, only fools would buy gasoline vehicles if the diesel option proves to be reliable and pays for itself 1.5 years and the owner is ahead by 30 grand over a dozen years at a usage rate of 20 thou miles annually. By the way, that would be remarkable!

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Old 01-24-2021, 08:17 PM   #82 (permalink)
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In Chevy vans it isn't a far fight. The choice is a 2.8L turbo diesel with an 8 speed or a 6.0L NA V8 with a 6 speed.

The Ford Transit has a fairer fight.

3.5L gas DI N/A V6
3.5L gas DI turbo
2.0L turbo diesel

All the engines get a 10 speed auto.

Given the current realities I can't see buying the diesel. Where I live diesel is more expensive than premium gas. Diesels have a particulate filter that will need to be replace somewhere around 120 - 150K miles. Expect to pay $4 - $5,000 for a shop to do it. Also, the fuel economy advantage isn't much between a DI turbo gas engine and a DI turbo diesel engine. It is basically just the extra energy content of the fuel.

My current TDI will be the last diesel I buy.
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Old 01-24-2021, 09:58 PM   #83 (permalink)
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Quote:
Originally Posted by JSH View Post
In Chevy vans it isn't a far fight. The choice is a 2.8L turbo diesel with an 8 speed or a 6.0L NA V8 with a 6 speed.

The Ford Transit has a fairer fight.

3.5L gas DI N/A V6
3.5L gas DI turbo
2.0L turbo diesel

All the engines get a 10 speed auto.

Given the current realities I can't see buying the diesel. Where I live diesel is more expensive than premium gas. Diesels have a particulate filter that will need to be replace somewhere around 120 - 150K miles. Expect to pay $4 - $5,000 for a shop to do it. Also, the fuel economy advantage isn't much between a DI turbo gas engine and a DI turbo diesel engine. It is basically just the extra energy content of the fuel.

My current TDI will be the last diesel I buy.
Thanks I was unaware of the operating costs, all I knew was every time my old friend had to repair any of the diesels trucks he said it cost from 2 to 4 times what a like job was on a gasoline engine.

Rich
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Old 01-24-2021, 10:00 PM   #84 (permalink)
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As for a official MPG I am still looking mean while enjoy all of this:

Personally I would believe the following reports way over any government test.

Rich

https://www.dieselplace.com/threads/...s-vans.950042/

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We are typically running about 7500 lbs GVW in Chicago traffic and also 100 mile runs on the highway. The little motor launches the van quite well, since it has way more bottom end than typical gas v-8's (325 ft lbs @ 1500 rpm, 370 @2000). In the city, it drives about the same as the 5.4 E 250 it replaced. On the highway, no trouble merging and accelerating while loaded. It’s no race car, but it’s fine.


I’ve never driven one of the big diesels, but to attempt to compare this 2.8 to engines over twice its size doesn’t seem to add up. Those big diesel vehicles have about 3 times the torque to weight ratio and about twice the HP to weight ratio of almost all production vehicles in the past 50 years. Yes this van will seem slow compared to those, but it has plenty of power for the typical user. At 180hp, this is more power than most small block V-8’s made until rather recently, and it has way more torque where its counts.


Fuel Economy is exceptional when heavily loaded. We run about 20 to 21 mpg city, and holding a steady 66 mph (at 65 it will downshift to 7th) we just got 33.3 mpg in humid 90 weather with A/C on over 60 miles, while running behind a semi, but not too close. This is probably about the best anyone could get running without any mods, as I had the speed control set at slightly over 65 to keep the tranny in 8th and then added a little extra as needed to maintain driving distance behind the semi. At this speed, the engine is engine running 1600 rpm (about 100 hp). On heavier grades, such as coming out of a river valley, it would downshift to 7th to maintain speed (2100 rpm/ 150 hp), but otherwise would stay in 8th. This is on relatively flat interstate of the Midwest. On open road without trailing a semi, we get a little over 30. At about 55 to 60 mph in heavy highway traffic entering a big city about 31.5 to 32 mpg...the other traffic helps pull and push you along due to drafting etc.


I've been hoping for a small diesel in a full size van for over 15 years. It provides the torque needed to get heavy loads moving, but sips fuel like a compact car.....a perfect combo for tradespeople. The big diesels never made any sense for regular tradesmen, since they don't almost never pull 15000 lb trailers, which I suspect is probably about 98% of the truck and van buyers. For that matter, must truck/van/ suv's are not carrying more than a couple of people, so it's about time a drive train was offered that fits this need quite well.


My only gripes have been the crappy factory shocks (this thing feels like our 2007 Jeep GC with 180,000 miles on it with the original struts) and the fact that the tranny holds low gears way too long. In city traffic this occurs about 35 MPH and it will hold the engine at about 2200 rpm until you accelerate to 37 mph, and on the highway....the trans will not upshift to high gear until 67 mph. On the highway it appears to be about a 10% hit in fuel economy at 65. In the city it’s a little harder to tell, but running 2200 rpm when you only need 1500 rpm or less can't be too good for economy. Again this is running about 7500 lb. GVW.


With the 20,000 miles per year we put on vans, the payback for the diesel upgrade is only about 18 months. If we keep the vehicle for 12 years (my daily driver is a 93), we should save about $30,000.00 on fuel costs over the 6.0 l v-8's that we have in other vans. The mileage is about double of the v-8s, maybe even more than double on the highway.


I do plan to complete some aero mods on the van that should bump the fuel economy up some more, since GM has done very little in this department and there's is a lot of room for improvement. I expect low to mid 30's mileage could be regularly attained with a loaded van, and maybe even better if running lighter.


With the couple exceptions noted above… shocks, trans holding gears too long and poor aero… this is a really good combination. While mileage is still way behind full size service vans sold in Europe (they get about 40 to 45 mpg with 1.4 L turbo diesels), for a heavy full framed vehicle this is exceptional. We will be buying more of these to replace the 6.0l gas equipped vans we have in service.


If put in full size pickups, this drivetrain is going to kill the Ford turbo full size trucks. They are only rated at 24 highway and rumored to get worse mileage than the v-8’s when worked hard.

The van is used for piping work, service and installation of steam boiler....so lots of weight all the time. WE are just under 7500 miles right now. And thank you for pointing out the van forum. I'll repost this initial post over there.

ricnick
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#14 • Mar 17, 2019 (Edited by Moderator)
2017 Chev Express w/ baby Dmax

Thought I'd liven this post up. I bought a new 2017 Chev Express 2500 cargo van short wheel base (or as I call them, the "stumpy") in July 2018. It has the 2.8L Dmax. I put 405 miles hwy service on mine a day on a harsh hwy short haul route in northern BC, Canada - my last point of call is actually 5 minutes from the southeast border of Alaska. I just rolled the van over 105000 kilometers this past week (65625 miles). I have had zero issues so far except for the aux fuel heater hose springing a leak which was fixed under warranty. I absolutely hammer this van hard every day with 2000 - 3000 pounds payload and it continues to deliver 30-35+ hwy MPG. I plan to keep it till it dies and then if the body and frame aren't rusted out, I intend to fix it up and run it some more. It has to go at least as far as my previous Express that had the 6.0L gas... which is now a shed with 972,000 km's on it!

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#19 • 5 mo ago
UPDATE- I now have 300,000 km's (186400 miles) on my 2017 Chevrolet Express 2500 with the 2.8L diesel. Bought this unit new in 2018 with a bit of doubt about how this engine would hold up to the work that I do. Well... I now have had my doubts silenced - this is a phenomenal engine, folks! I work it hard day in and day out and get a consistent 26 - 28MPG on the hwy loaded down even at the higher mileage it has now. So far biggest repairs have been the serpentine belt twice, timing belt at 242k & was getting turbo blow by around 270,000 kms - had to get the turbo gaskets replaced. Other than that... just regular oil changes & fuel filter changes. I love this van so much thinking of getting an extended one next and get built up with 4x4. www.facebook.com/SBEDmax

Last edited by racprops; 01-24-2021 at 10:20 PM..
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Old 01-25-2021, 03:07 PM   #85 (permalink)
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OMG ANOTHER ONE and this one is OFFICIAL...A 29MPG gasoline van:

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