off topic, but was there still rumours of a Cummins engine being slapped into a Toyota product?
I think that died a long time ago. It was the Cummins 5.0 v8 that ended up in the Nissan Titan for a couple years. But it was both thirsty and unreliable. My guess is Toyota was pursuing it and then rejected it after testing, but that's just pure speculation on my part. Toyota's own new 3.3L v6 Turbo Diesel isn't likely either. It's 304/516. So it's a little less than the Cummins, but probably 50% better on fuel efficiency. USA emissions are too expensive to meet and end up with unreliable engines like every other modern diesel.
Cummins 5.0 was 310/555 and only got about 17mpg combined (no epa rating I could find quickly) - Fuelly says average titan mpg is about 12.5. Tundra hybrid is 437hp/583tq. And I'm guessing about 21mpg. So there's really no reason for Toyota to also have a diesel in addition when its hybrid has better fuel efficiency, costs less, and has more power.
I'm betting in the next few years we'll see a v8 turbo hybrid gasser that'll be a sign of the end for diesels in HD trucks. If you scale up Toyota's 3.4TTv6 hybrid to a 6.0 v8 - just a linear scale up, you end up at 770hp and a bit over 1,000 tq. That would be competitive with any current HD diesel. If it could squeeze out 20 city/20highway unloaded it'd make diesel obsolete. In side by side tests modern diesel HD trucks only beat their gas counterparts by 1 or so mpg. Adding the hybrid would probably cancel that out. And no more EGR systems full of soot to fix, no more $12,000 bills for fuel system replacement, no more $450/ea injectors that need to be replaced periodically, no more glow plug tips gone missing in the cylinders, no more 16 gallon oil changes, no more $250 fuel filters every year, no more fuel gelling in winter, - basically no more diesel bull shit to deal with!
OTOH - the Ford Powerboost on TFL's testing had lower towing mpg than the normal 3.5EB. So I'm really curious to see how the tundra does towing between the normal and hybrid versions. The tundra hybrid is really a bummer - battery is way too small to do what it needs for good towing mpg.
