Ford diesel vs Chevy diesel vs dodge diesel?

Answer 1

The first Ford diesel was a naturally aspirated 6.9 liter diesel engine. When a turbo is added to it, it can hold its own. After that, they went with a 7.3 Navistar-International V8 diesel engine, which, while reliable, was a bit underpowered, and that's why it got smoked by the 6BT Cummins, in spite of having 7.3 liters displacement vs. the 6BT's 5.9 liters. The 6.0 and 6.4 Powerstroke were also Navistar engines, and incorporated a very faulty high pressure oil system, as well as a cheap knockoff of Caterpillar's HEUI injectors. They were junk. Ford currently has a 6.7 liter diesel engine not made by Navistar, and it seems to hold up pretty well - the downside being that it's an EPA2010 engine, and thus has the DPF, DEF, and SCR nonsense.

Dodge started with a 2.2 liter Mitsubishi diesel in the late 1970s. It was a dog. You do not want this. Their partnership with Cummins made great headway in the light/medium duty truck markets when the 6BT (originally designed for farm and construction equipment) became available as an on-highway diesel engine in 1989. Over the years, some design changes occurred, and most of them weren't for the better - the original 12 valve design was better than the later 24 valve design, and switching from common rail to direct injection wasn't an improvement, by any means. But, the 5.9 gave excellent service throughout its lifespan. It was just unfortunate that it was coupled to a Dodge.

GM originally used the naturally aspirated 5.7 Olds diesel in the late 70s/early 80s. A common misconception is that this engine was a gas engine redesigned to be a diesel engine - this is simply not true. After the 5.7 Olds diesel, GM turned to the Detroit Diesel Corporation, and introduced the 6.2 Detroit Diesel into the lineup in 1984. Although not a highly touted engine, it was more widespread than many people realized, as it powered not only the military Commercial Utility Cargo Vehicles (Chevrolet Blazers and pickups, militarized), but also the first generation of the AM General HMMWV ("Humvee"). While a fairly solid engine, with the added bonus of being able to accept the turbo from a 6.5, cracking in the heads is a common problem with this one. When the 5.9 Cummins 6BT and 7.3 Navistar came into the market, the Detroit no longer could hang, and GM turned to Isuzu. Thus, the 6.5 LB7 diesel came into play, and was later replaced by the 6.6 liter Isuzu diesel.