I drive a 2006 Chevy Express 2500 with the Duramax 6.6 liter. I love it and it has been good to me. The power that modern turbodiesels produce is a godsend for those who pull trailers out here in the west.
However, izifaddag is right about these new generation turbodiesels having complicated systems that are more expensive and can produce catastrophic cascading failures of the systems if their (thankfully few) weaknesses are not addressed and kept under watchful eye.
Here is the rub;...older generation diesels are cheaper to buy, cheaper to fix, less likely to have failures of important systems in the first place, and are also amenable to being run on nearly free waste cooking oil/grease when properly configured to do so. But these benefits are at the cost of much lesser performance than when compared to newer generation turbodiesels.
For instance, lets compare my 2006 Duramax 6.6 motor's performance to a 1996 Chevy 6.5 diesel. The 6.5 (which is a version of the 6.2 that powers the military Hummer) in 1996 produced 180 HP at 360 foot pounds of torque. My more modern turbodiesel van produces 250 horsepower at 440 foot pounds of torque. With that increase, I'm able to haul a trailer that the van from 10 years before would struggle with. And my van model of Duramax is REDUCED/DETUNED from what the trucks that same year were set up to do, which was 360 HP at 650 Ft lbs of TQ.
In vans, there are really only 2 options for the diesels, since Dodge never put one in their vans. The most common you will find are Fords, with Chevys being less common.
You will here legendary tales of how Ford diesels are a trap that will undo you at the worst moment and destroy your wallet. That is an over-hyped exaggeration of something that is based on some unfortunately true history, but is not nearly as bad a problem (in the vans, anyway) as has been wailed about.
This stems from the problem-plagued 6.0 liter Powerstroke motor that was produced from 2003-2010. I stress that the problems with the 6.0 were nearly all and entirely a phenomenon with the TRUCKS, NOT THE VANS. The reason is because due to the smaller and confined engine space available in the vans, the Powerstrokes (and Duramaxes in Chevys as well) were DETUNED (reduced in performance output) to prevent issues with heat generation and inadequate airflow in those engine bays to carry that heat away. Heat is the deadliest threat to diesel motors. And if they cannot be appropriately cooled, they will die an early death. Unable to get more airflow through the engine bays of the vans, the solution was to generate less heat by not putting out as much power as those found in the roomier and higher airflow engine bays of the pickups. While disappointing to us power freaks who always want more power,...it nearly eliminated the failures the 6.0 Powerstrokes were having in their trucks.
The 1995-2003 7.3 Ford Powerstroke vans never had the stigma the later 6.0s did and are quite reliable and legendary for it. They are in at least one way slightly better than the 6.0 that came after it, in that they operate at a lower PSI in their injectors and with larger orifices. This makes the 7.3 Powerstroke perhaps the only modern diesel van that can be modified to run on cheap used cooking oil or a blended mix of cooking oil and diesel or various biodiesel blends.
The Chevy 6.6 Duramax wasn't available in the Express series until 2005, even though they had been in the trucks since 2001. There have been no scandals with these of any kind that I am aware of. They have earned a reputation of being exactly as reliable as their pickup truck counterparts. While Ford produced more vans, as well as diesel vans, since 2001, the majority of diesel-powered ambulances you see on the road are Chevys, not Fords.
A used Ford turbodiesel van usually costs less than a Chevy TD of the same year, mostly because of the word on the street about the bad 6.0s that plagued the pickups. But had I not have happened to have found my Chevy at the sweet price I did, I was actually expecting to acquire a Ford, either 7.3 or 6.0, and would have been comfortable with that choice. But as it was, I found my 2006 Express 2500 former locksmithing van with 218,000 miles on it for just $4200. That was about $2000 less than it should have been selling for and in the price range I was looking to spend on a Ford of similar mileage. I've since then had it for a year now and put another 22,000 miles on it without issue. I expect it will go another 100,000 miles.
