10 speed, although that is irrelevant to my arguement. Speed is a macho issue, it's not a necessity.

 

I didn't reply back because I was trying to find data, which is tough to do without an SAE membership. Frictional losses in an engine are significant, and much of that has to do with the size of the engine. Found an interesting slideshow on the subject, but didn't have time to go through it in detail:

http://web.mit.edu/2.61/www/Lecture%...0tribology.pdf

Anywho, pumping losses in gasoline engines are huge compared to frictional losses, so undoubtedly there's more to gain with a smaller gasoline engine compared to a diesel. Smaller displacement typically means it runs under higher load at a given engine speed, which means less is wasted sucking air past the throttle plate, and higher efficiency.

Diesel engines don't suffer from that, but smaller displacement would still mean less energy is lost to internal friction. Take that concept to extremes, imagine trying to pull start your 6.0L like you do a Briggs and Stratton. Likewise a 5.0L engine would take less energy to turn than a larger 6.7L. I'm not sure just how much would be saved, but I think it's possible to see a noticeable improvement.

 

I think the 1/2 ton diesels will be or already are financial disasters for ram, gm, and Nissan. One problem being they cost as much as the mainstay 3/4 and one ton big boys already out there. Then they had totally different engines. Then there is the Colorado.... I think ford is smart to stay out of it.
I think a better idea is a little mini truck diesel that gets killer mpg and purrs.

 

I was actually more curious if people were willing to "settle" for only 700 lb ft if it meant noticeable cost savings. It's been a few years now since engine work on diesels meant peeling the cab which made me think we hit crazy, but the power just keeps climbing.

Anyway, I'm learning a lot and really enjoying the discussion.

Show of hands...who honestly needs 925 lb ft in an F250 or F350? Grin factor I totally get, but need?

 

I think it would make more sense to make the current engines because of economies of scale and just detune them like in the larger F-Series. I have never understood the lack of options from the factory to set the power levels to say Economy, Stock, Tow like an aftermarket tuner. I would much prefer the reliability and longevity of a diesel but also actually see the fuel economy also. It doesn't seem like fuel economy has gone up much in the last 20 years, only power levels and I think that needs to change.

 

I realize it's way after the fact, but I found it interesting that Ford designed a V8 instead of an inline 6, which is inherently smoother and trends to develop more torque just by nature of the design.

I would 100% love a fuel miser mode, with whatever makes sense for a turbo diesel, whether that's cylinder deactivation or whatever else. It's immensely frustrating to me that the particulate filter badly hamstrings fuel mileage. Sometimes I wish I had kept the off-road tuner I had and eliminated the DPF. I'd have probably eliminated the EGR as well, but I don't mind the DEF system. It's not expensive or painful to maintain, and if it helps reduce greenhouse gasses (NOx), that's good as far as I'm concerned.

I love my 2011 6.7L with the 400hp/800tq. Ratchet that up and give me 440hp/925tq and I'd love it even more, I'm sure. Makes passing on country roads that much quicker and safer, and when using those abbreviated country on-ramps when hauling or towing heavy there's that much less white knuckling involved in not getting run over by people already on the highway.

But if I had to get rid of this truck (no plans, 67k miles and paid off next year, hoping to keep it for a long time) I'd very seriously consider the 6.2L gasser. Simpler, cheaper, lighter, less maintenance and fewer things to go wrong, fill up at any gas station, walk right by the boxes of DEF, and still does the job better than diesels of yesteryear.

Out of a diesel I expect massive torque, an exhaust brake that pulls you forward against your seatbelt's chest strap, and mileage over 20mpg when running empty. The 6.7L delivers the first but not the second two. I'm still happy with it, but the only thing other than a disaster that would convince me to replace this truck would be something that checks all those boxes.

 

I was looking for a 6.2 or 6.8 when I ended up with a 6.0. I like this 6.0, warts and all. You can plug down $300 to $500 and have an instant 100 horses and torque with the push of a few buttons. That instant horsepower increase comes at a price. If you're not careful you can gernade an engine.

Instead of a smaller displacement engine why not have a factory controlled tuner? Something that will give economy and something engineered to give more power without the risk of screwing up an engine.

The horsepower and torque ratings are in the range of semi trucks from 20 to 30 years ago.

 

The question that needs to asked, How much horsepower/torque can I have and still go to heaven?

 

That should be any time now, right??? Lol

 

I could go for a factory tuner or anything else to get better economy. In my mind, 700 lb ft would be at the low end of overkill for a light duty truck...900 lb ft is crazy. To me more power in the same engine means it's working more efficiently. I hope those same principles could be used to make the same engine more economical. I can understand Ford making a diesel for medium duty and also putting it in the light duty line up to save cost of developing a separate diesel platform. So if a factory tuner is a way to bring sanity and practicality to the light duty world then cool.

 

I think the future of diesels is making them more affordable to buy and own. Right now, they are selling significantly more diesels to folks who do not require the capabilities of the diesel often enough to justify the initial purchase price or the cost of ownership. As these prices continue to climb I think you are going to see diesels only purchased by the few who really can justify those costs.

Until those costs stabilize, which doesn't seem likely anytime soon, their popularity is going to ebb a bit.

To answer the OPs question, I think the answer is no. There is already a diesel in place for the SD. Why would they want to add another with 75% of the one they already have? Do you really want a diesel truck but not the 6.7 or are you just ruminating on diesels a little for fun?

I really don't believe how many diesel trucks the companies sell these days. I am a heavy equipment diesel mechanic and when Tier 4 hit all the construction companies I deal with stopped buying new equipment until they absolutely had to and then they dickered for longer warranties on the engine and associated components when they did finally buy new. I know many folks who feel the same way about the diesel powered light trucks.

I know quite a bit about diesels and they don't intimidate me to work on yet, I bought a gas truck. I knew I could never justify owning a diesel truck so I made the best economical choice for me. I am dismayed at how many others are not.

 

I'm not suggesting add another diesel to the light duty line up...I'm suggesting it would be nice to have a diesel that belongs in the light duty line up instead of transplanting a medium duty engine into a light duty chassis.

I have a 2002 diesel and based on how easily it handles my 10k trailer, I imagine the new 6.7 would be way over powered for the application. To me, a smaller engine would allow more elbow room under the hood and save both purchase money and fuel money.

A light duty truck cannot make use of the 6.7's power. Ford isn't alone in over stuffing this market segment...the other companies are doing it too. The current power race is to get the most power out of 6-7 liters. I'd like to see a race to get 700-ish lb ft out of fewer and fewer liters.

 

What?

Few buying decisions are made on economical bases alone. If it were, few would ever buy a new vehicle. And you wouldn't have bought an oversize truck for your personal enjoyment.

 

Interesting discussion. If you look at cars, there are usually 2 and sometimes 3 engine options available for the same car brand and platform. i.e. VW. Why? Different strokes for different folks (and different reasons).

Example: we bought a 6 cylinder RAV and when SWMBO asked why not go with the 4 cylinder engine like our previous Camry's (3 of them), I said towing capacity (3,500 lbs. vs. 1,500 lbs.) and passing power/safety margin. The mileage penalty is only 1 mpg for the 6 cylinder over the four banger. This past weekend she understood the passing safety margin reason first hand due to a highway driving situation she found herself in.

Diesels have a lower adoption rate in N.A then elsewhere in the world. Perhaps this would change with more diesel engine choices and economies of scale (production volume).

 

I realize it's a chicken-and-egg thing, but in the US diesel is generally viewed as a "dirty" fuel, more so than Europe. So the EPA makes life harder on diesels than Europe (and certain the third world, of course), which ends up defeating the main draw of modern diesels in passenger cars for most: greater power with greater efficiency and million mile reliability and simplicity. The DPF itself drops MPG substantially, which kills most of the draw. The HPFP and so forth contribute to scary what-if scenarios. And with improvements and advancements in gasoline engines via direct injection, forced induction, variable timing, and all the rest, the motivation to pursue diesel is reduced.

Especially in the "heavy duty" (in consumer terms) truck world, where profit margins are high and configuration options are already extensive, having multiple gas and multiple diesel choices isn't particularly alluring to manufacturers--especially when fuel economy numbers are not required and thus don't count against CAFE. In the Ford Super Duty line, we have a very capable and simple 6.2L gasser with 385hp and 430 foot pounds of torque, rivaling the diesels of yesteryear. And the 6.7L monster diesel with 440hp and 925 foot pounds, you can't ask for more.

So for those who want a fuel sipping SD for a daily driver, they're in the wrong market segment to begin with, and they can get an F150 with towing specs that are up there with the 3/4- and 1-ton trucks of not too long ago, and it has lots of different engine options.

So I mean, really, there's not much reason for Ford to put a lot of effort into a small diesel in a truck market dominated by existing powerful options. If anything they would be more incentivized to come up with a hybrid system that uses electric power to supplement acceleration for a smaller forced-induction gas engine. While batteries are heavy, it shouldn't impact GVWR much of any because the weight of the diesel is enough that going with a lightweight gas engine plus batteries shouldn't tip the scales.