Diesel 4Runner?

[philsey]

Very interesting post [MENTION=93267]terminus[/MENTION]. It's good to hear from someone informed on this subject.

.....
Just to give you a bit of background, I've been testing/developing euro diesel engines in the US since the late 90's......

So, that's >15 years. Seems like pretty slow progress to me. Care to expound?

 

[JeremyB]

I thought the largest problem with importing European diesels was the strict US emission requirements. At least that's what I read in my SAE magazines a few years back.

US has very strict NOx requirements compared to Europe. [Light passenger vehicles]
0.070 g/mi - USA (fleet average)
0.289 g/mi - Europe

Europe is dropping to 0.129 g/mi NOx by 09/2014

From what little I've read, NOx is a very difficult emission to reduce.

 

[chmura]

Modern diesels are very very complex and are computer controlled. The days off slapping on a snorkel in a diesel and submerging the entire engine during water crossings and drive away without worrying are long long gone. If you seen camel trophy videos you know what I'm talking about.

There after-treatment systems, DPF's, SCR (selective catalytic reduction) basically ammonia gets injected into the exhaust stream and this reduces NOx down to very low levels. But this is dependent on duty cycle, temperature, etc. SCR will not start dosing ammonia until all conditions are met, temp, back pressure, etc. Than you have a DPF to filter out the soot (PM), which there are many variants of them. They have injectors in the exhaust to dose fuel into the exhaust stream to create high temperature to burn off the soot from the filter walls. Again this is dependent on duty cycle. If you are always on the highway cruising at freeway speeds this creates enough heat to burn the soot off the filter passively. And they play games with EGR to create heat also. Which diesels hate EGR's. Every manufacturer has their own strategy on these systems. In semi tractor world these systems cost around $20k and bring the price of the vehicle up significantly.

This is why we do not see many diesels in the US.

By saying all that I would take a reliable iron block V8 over a modern diesel today. Maybe in 10 years when these systems are more proven and everyone uses the same strategy I would buy a diesel.

 

[apextaco]

I think the main obstacle for Toyota is that their bread and butter diesels are for light industrial applications, ie forklifts. These engines although light-duty are still too heavy (expensive) for automotive part load conditions. The sales volume is not there to support the capex requirements. The tech is already available and very well understood so it really comes down to economics.

By bet is CNG. Although not as efficient the fuel is cheap and conversions are simple. The owning and operating costs will win. We just need the EPA to not make the certification an obstacle like it is today.

 

[terminus]

Very interesting post [MENTION=93267]terminus[/MENTION]. It's good to hear from someone informed on this subject.



So, that's >15 years. Seems like pretty slow progress to me. Care to expound?

Well, I do get paid by the hour...

But seriously, it's all product strategy & risk management. Yes, there are customers who want them but how many will pay the premium for it? What about sourcing? There's a lot of advantages to having a plant in the US to serve that market, and the same goes for other countries. But a new plant is a MAJOR headache. Not to mention new suppliers. So even if you have an existing engine designed for other markets that is on the shelf and ready to go (which is never the case, of course) it's a big pain in the ass. Plus, the subtleties of diesel engine design can require significant R&D to overcome. And the complexity of the emissions system is daunting, but so is the fuel system. I work on a lot of proprietary designs, so I have to be careful what I say. Just to give you an idea, here's some common issues I've seen with just the fuel systems on these engines.

Modern diesels with common rail injection run really high pressures. Think 30,000 psi. That's a non-trivial engineering challenge. The high cyclic pressure fatigues metal fuel lines in short order. And with 30,000 psi there's no such thing as a slow leak. They're all catastrophic. Plus the misfire that occurs after the ruptured fuel line causes a high spike in torsional acceleration, which can fail the clutch or other driveline components.

Another problem with the fuel systems is the high pressure pump uses diesel fuel as a lubricant. This usually works just fine but when it doesn't (often due to dirty or poor quality fuel) things get ugly fast. The rest of the fuel system gets taken out like domino's. Fuel injectors are another challenge. Modern ones are amazing at how precisely they regulate fuel, capable of pilot injection and all that. But they still fail, and they can cause a lot of damage in the process. And I'm not even going to get into the hydraulic resonance issues. You know the water hammer you can get in your house plumbing? Just imagine what could happen at these high pressures and the high frequency opening/closing of the injectors.

OK, last example, just because this blew my mind at the time. I was working on a new engine design for almost two years (still on the computer, at this point). We built the first actual prototype engines are we were all pretty excited & nervous. The company had invested over $2 billion at this point! All the prototypes failed, and failed quickly. Post mortem teardown revealed the pistons had all failed. After a bit of head scratching and a few experiments, we figured it out. The fuel was injected at such a high pressure, that any small amount that was still liquid (not vaporized) hit the pistons so hard it put a hole in it. Yes, diesel fuel put holes in the pistons. That one took me a while to wrap my head around :biggrin2:

Sorry for the long answer, but I figured it was either that or a start a "which tire" thread...

 

[BlackWorksInc]

To add to Terminus's point on the fuel puncturing the pistons. Water Jet Cutting is roughly similar in practice. They literally cut inches thick alloy/ceramic tank armor with pressurized water. These Diesel systems run ridiculous amounts of pressure and they are very dangerous to work on if you don't know how to properly deal with them!

 

[harper7]

I would love to see a diesel 4runner, but I'm a little skeptical that Toyota would do it without a big cost increase. The high compression ratio makes engine block design a real challenge and the fuel system and exhaust systems (including the particulate filter) are crazy expensive, too. To say nothing of all the precious metals that are needed in the catalyst. I'm not saying it won't happen, but I think a 6 or 8 cylinder would be cost prohibitive due to engine costs and the upgrades to the drivetrain that would be required. I'd ballpark it at $5,500 increase, depending on how many markets they could amortize the costs over. Personally, I think the value proposition of a 4runner gets very close to the edge of the cliff with an extra $5k tacked on. A 4 cylinder would be more feasible, but I think the US market would likely reject that. I would probably be the one guy in line with my checkbook , though.

Great post!

They do already have DI 3.0L turbo diesel engines that they sell all over most of the world except North America and have for years. It's the 1KZ-TE Toyota KZ engine and the 1KD-FTV Toyota KD engine that also goes in the 4Runner's brother the LC Prado as an option running right down the same Lexus Tahara assembly line. They also share our dual vvt-i V6 engines using the same updated J150 platform. Toyota Land Cruiser Prado

They had 2 engine options in 2010 for 5th Gens and the 4 banger gasser didn't sell and they lost on that gamble . Big waste of money for Toyota for R&D and to have it certified for the 4Runner and sell so very very few as they are quite rare as not many dealers ordered them at all.

Toyota recently insinuated that there would be a surprise for the 2014 and it very well could be a second engine option and hopes are high that they will take the gamble again, only on the turbo diesel or V8 this time.

 

[Quentin]

I think the 4.6L is more likely than a diesel.

 

[philsey]

NO company does ANYTHING without cost-justification in the form of an ROI.

If we were talking about putting an existing 4 cyl T/C diesel in several high volume sellers, say the Corolla and the RAV and the Camry, then the sales numbers might be there. But the diesel sales volumes for an appropriate I-6 or V-8 diesel, even combining 4R plus Tundra plus Tacoma, just cannot create enough ROI for such a project.

AFAIK, Toyota has no diesel engine in NA. Hence no service training, no parts supply or distribution, no advertising, no sales training, no EPA certification, etc etc. Cost justifying such huge up-front expenses requires profit, in volumes that will never come from the 4R and it's ilk.

It's just not gonna happen.... [edit ... in the 4Runner].

 

[Jayhawk5G]

NO company does ANYTHING without cost-justification in the form of an ROI.

If we were talking about putting an existing 4 cyl T/C diesel in several high volume sellers, say the Corolla and the RAV and the Camry, then the sales numbers might be there. But the diesel sales volumes for an appropriate I-6 or V-8 diesel, even combining 4R plus Tundra plus Tacoma, just cannot create enough ROI for such a project.

AFAIK, Toyota has no diesel engine in NA. Hence no service training, no parts supply or distribution, no advertising, no sales training, no EPA certification, etc etc. Cost justifying such huge up-front expenses requires profit, in volumes that will never come from the 4R and it's ilk.

It's just not gonna happen....

The initial thought behind my post is that for the longest time few diesel options were available in the US. The TDi being the most common, with Mercedes and BMW recently bringing more to market. It seems like we are finally at the peak where in the next two years the number of diesel passenger vehicles is pretty much going to double from whats offered now. If diesel becomes popular and sells well, I don't think it would be crazy to assume that this might make Toyota consider bringing their own diesel to market... The Tundra very well may be the first, and Toyota is missing out on the 2500 and 3500 market, by only offering a gas 1500.

 

[dekeman]

... hopes are high that they will take the gamble again, only on the turbo diesel or V8 this time.

Yes, we soldier on with high hopes, but, alas, this was the most recent spy shot from Toyota testing grounds.....

 

[philsey]

* [MENTION=48776]dekeman[/MENTION] newsflash *

Honda announces a diesel outboard ....

 

[1engineer]

Am I the only one here to not BS?
Holy crap, I would have to be out of my MIND to even want or care about a diesel option in a 4,600 lb SUV. Why? So I can pay the $5,000 or so additional dollars to have it pay for itself in, oh, (doing math) hmm, let's see: 30% better efficiency so say 26 mpg. Gas is $3.60 a gallon and I drive 20K miles a year. Alright, I spend about $3,600.00 now a year on gas so diesel, EVEN if it were the same price as gas would be $2,769.00 a year for a grand total savings of, wait for it, wwwaaaiiittt for it, $831.00 a year. So it will take you SIX years and 120,000 miles JUST TO BREAK EVEN. Knowing diesel is higher priced than gasoline it would really take you around seven years to break even.

So efficiency and saving money is not the answer so what about torque? OK, let's look at that:

30% more torque will certainly help you pull a trailer up a hill but will not be of much use anywhere else. Don't agree with me? Alright, somebody go find a hill that right now the 4Runner will not climb in low range because it absolutely does not have enough horsepower or torque to climb. It just sits there. Yeah, I didn't think you could find that either. So, I will give you that.. it will be helpful pulling a trailer but it will not add anything to the capacity of 5K because unfortunately engine torque is not the limiting factor of trailer weight pulling fellas. Never mind that a 3/4 ton diesel pickup truck is built to pull about 4X the trailer weight as a 4Runner, for not a lot of money more.

How about longevity? Say a Toyota gas engine lasts 300K miles and a Toyota diesel lasts 500K miles. It is going to take you (using 20K/yr) 15 YEARS to go 300K and 25 YEARS to go 500K! A very few of you will keep your vehicle that long, and what is that vehicle worth then? I can answer that: Not much.

So, not really economical, not really adding any capacity, what is it then that 50 or so guys on a Toyota enthusiast forum is making a diesel look so inviting? Coolness factor?


Listen, I wrote this tongue-in-cheek because I am trying to understand why anyone would want a diesel in a bigger SUV. In 2012 about 1.2% of passenger vehicles bought in the US were diesel. Yes, that number is up a whopping 34% from 2011 so a lot more people are buying diesel, unfortunately 98.8% of the public is yawning. I am all for diesels in certain applications where torque and/or efficiency can make a real difference. It makes sense for: 18 wheelers, heavy duty pickups and really small, light cars. A Toyota 4Runner? Not so much. If they could offer a diesel option at the same price as gasoline then it would make sense. Unfortunately that will never happen.

 

[philsey]

:lalala:

Here, let me condense this fer ya:

.... Coolness factor?

Yes.

You're welcome.

 

[dekeman]

Greg's right about it not happening — though the interest is a little wider than many of us suspect, aided also by the need to lower the CAFE. Either way, the crystal ball is clear with six numbers that continue to be visible: 2014=4.6

 

[Jayhawk5G]

I think there is more to a diesel option than the coolness factor... I'm very surprised that the weight of the vehicle was brought up, the added torque of a diesel engine is perfect for a vehicle of this weight because full hp/tq are available at very low rpm and held. It would take care of a number of the complaints people have about how sluggish the 5th gen is at part throttle. It gets much better mileage than the current engine, there are ways to improve hp/tq and mpg as well through mods. I also don't think it would translate to an actual $5k over current prices. Jeep from my understanding is putting the diesel with the more upscale models for the most part.

If diesel was as cost-prohibitive as it's being made out... why on earth are so many manufacturers bringing them to market here?

 

[M1911]

I think the 4.6L is more likely than a diesel.

With higher CAFE standards on the way, that is just not gonna happen.

 

[1engineer]

I think there is more to a diesel option than the coolness factor... I'm very surprised that the weight of the vehicle was brought up, the added torque of a diesel engine is perfect for a vehicle of this weight because full hp/tq are available at very low rpm and held. It would take care of a number of the complaints people have about how sluggish the 5th gen is at part throttle. It gets much better mileage than the current engine, there are ways to improve hp/tq and mpg as well through mods. I also don't think it would translate to an actual $5k over current prices. Jeep from my understanding is putting the diesel with the more upscale models for the most part.

If diesel was as cost-prohibitive as it's being made out... why on earth are so many manufacturers bringing them to market here?

You can justify it in your mind all you like but the real world of fact does not agree. Again, heavy towing vehicles or tiny little cars make the most sense for diesels, nothing else.
You keep bringing up Jeep and Dodge: Do you know why they (and GM to an extent) and the European manufacturers are trying to bring diesel to the table? They have no other option but diesel and they are trying to use what they have to improve their CAFE numbers. Read the whole article Corporate Average Fuel Economy - Wikipedia, the free encyclopedia to fully understand. The Asian manufacturers bet on something different 20 years ago and started developing hybrid drive tech in ADDITION to diesel. Dodge and those guys sat on their a$$ and now they are pushing the only thing they have. At least Ford built a little better turbo and engine management system to augment their fuel economy figures. Oh, the domestic and European guys OFFER hybrid drives but their tech is laughable compared to Prius tech. The Chevy Volt? C'mon, what's it sold so far?

Never forget the only motivation driving the OEM's for fuel economy is our beloved federal government. The consumer as a whole is very fickle: Gas prices go up they want small vehicles. Gas prices go down they want big vehicles, and will buy the least efficient vehicle they can afford to fuel as a collective. Not too many millionaires drive a Toyota Yaris or a Chevy Sonic even though they make sense, yet people on welfare will drive Chevy Tahoes because they somehow can afford the gas.

So the OEM's are motivated by the EPA because they have to pay a penalty if their numbers fall to a certain point. Dodge says "Let's offer a diesel, make it sound like this is the best thing since sliced bread and maybe somebody will fall for the bells and whistles and bullet points and buy the things. If they do, we can meet our CAFE standards." Toyota says "Let's expand our Prius hybrid line that makes sense and still offer vehicles such as the 4Runner to customers and we will still meet the CAFE numbers." Honda says "Let's keep building underpowered but efficient cars and we will be fine." Ford says "Alright! The Ecoboost marketing ploy was a success! Put it in everything!" And my favorite: GM says "We spent so much money on the Volt development to sell just a few vehicles we can't offer anything else at this time. Thank goodness the federal government still is the majority stock holder in our company. They won't do anything to mess that up!"

 

[dekeman]

With higher CAFE standards on the way, that is just not gonna happen.

4.6 will happen if it gets, on paper, better mpg than the 4.0, which is entirely possible with DI and a six speed. Despite the two extra pots, the V8 won't have to work as hard as the six to achieve or maintain the same momentum, a bit like the M3 race against the Prius, where the M3 used less fuel. (absurdly extreme example.)

 

[dekeman]

The Ecoboost marketing ploy was a success!

All my tests with the EcoBoost V6 consistently return the same mpg as the 5.0 V8. Even my time with the 6.7 powerstroke came in close to the turbo V6, though the truck was an F-350 compared to a 150. Gotta say that powerstoke felt good! Was almost able to pull Greenland further south.