80 series diesel or gas

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Has been for twenty years sir!
Used seven days a week and all family holidays.
 
What?
I get 30 without even trying, and it's hilly round here.
UK gallons are bigger than US gallons, as a result your mpg numbers will be higher for the same actual fuel consumption. Is that mileage figure calculated by odometer readings with a topped off tank? I regularly have people tell me their full size American pickup gets upper 20’s or even low 30’s mpg US, but they’ve never actually hand calculated mpg from tank to tank. In reality no full size pickup will get more than about 20-22mpg unless under absolute ideal conditions.

Average speed, altitude and terrain also play a big role; I can get nearly 30 mpg US in the mountains of western Montana with my TDI swapped LC if I take backroads and keep my speed around 50-65mph. On flat ground at sea level I could probably break the 30mpg mark, but I usually don’t have the patience for that kind of driving and usually do 70-77mph on the highways.
 
25 uk imperial gallons converted to US gallons is 30.

I use a mpg calculator. So litres put in the tank compared to odo readings over a period of time.
I'm happy to be corrected.
 
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Maybe. But it would come at a cost of long term reliability, which is completely unacceptable to me personally.

Not necesarily true at all.

Toyota tuned the 80s very conservatively.
More boost gives you a cleaner more efficient burn, and lower combustion temperatures.
Its arguable that a more efficient turbo and a careful tune would imprive the life of the engine.

Push this to extremes, and drive like a peanut, then the longevity is compromised.

The same engines were built as marine engines and produced double to power outoutas a Yanmar marine engine.
 
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I get that there are too many variables at play for any one anecdotal data point to mean much, but FWIW, my FTE/A750F was getting up to 375-390 miles per tank before the fuel light began to blip. Fill-upswere usually right at ~20.5 US/Gal at auto shut off.

This is a '97 LX450 with a 2005 Euro VNT turboed FTE paired to the A750F auto five-speed so I don't know how that compares to the mechanical 24-valve engines or other transmissions. My cruiser also is a very heavily built truck with loaded drawers, fridge, armor, etc. Until recently I was spinning Icon Rebound Pros with 37" KO3s and 4.88 gears as well.

Over the summer, I hopped for a set of Hutchinson beadlocks on 37's and my mileage definitely took a considerable hit. I'm now getting 320-340 miles per tank with mixed use. Those damn Rock Monsters are friggin' heavy bastards.
 
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Would you say the diesel is a good daily driver?
Yes. I’d say that’s what they were built for.

With the exception of the motor and manual transmission pretty much everything is the same as the US spec cars. If you think you’d daily a 25-30 year old US spec 80, with all that entails, then you’d be fine daily driving an import diesel 80 if you want to. That said, if you don’t do your own wrenching you may have a hard time finding a reputable mechanic to service the diesel since those motors were never sold here. OTOH, if you are capable of doing your own service then pretty much anything you’d need is available. Note that as these vehicles age, that may change.

The diesel motors in these trucks are notoriously reliable when properly maintained. Baseline it when you get it, keep up with service, pay attention to any odd noises or behaviors, maybe keep some common service items on hand, and don’t beat on it and the motor will probably outlive you.

And yes, it’s going to cost money.
 
What?
I get 30 without even trying, and it's hilly round here.
As mentioned before, UK gallons are not the same as US gallons.

But even then, i still have a very hard time believing numbers like this. Not only based on my own personal (rather extensive) experience with these trucks/engines, but also Toyota's own numbers.

For 1995-1997 trucks, with 24V TD and MT original claimed highway fuel consumption by Toyota was 11.2L/100KM. Which translates to 21 US MPG.
This claimed number would be under IDEAL test conditions, brand new vehicle, no modifications and running street/highway tires. These conditions are not realistic for 99.99% of 80-series owners out there, and i have NEVER seen a vehicle (ANY vehicle) from that era achieve their manufacturers fuel consumption claimed numbers in real world. So when i see people claiming 20% better fuel economy (25MPG) out of these trucks when they're 30 years old, lifted, overweight and riding on 35" mud terrains, you can see where my skepticism comes from...

And another point i brought up earlier - Toyota's advertised highway MPG numbers for the US 1997 FZJ80 were 15MPG, which makes this a pretty consistent number considering 40% less energy density for gasoline (in lab environment). How often do you see anyone claiming they're getting better than advertised fuel economy with FZJ ? Yep, pretty much never. So, someone please explain to me: how is it possible to get 66% (25mpg vs 15mpg) better fuel economy when diesel fuel only has 40% more potential energy in it (which you will NEVER be able to utilize fully in real world)? The math/physics just don't add up.

Not necesarily true at all.

Toyota tuned the 80s very conservatively.
More boost gives you a cleaner more efficient burn, and lower combustion temperatures.
Its arguable that a more efficient turbo and a careful tune would imprive the life of the engine.

Push this to extremes, and drive like a peanut, then the longevity is compromised.

The same engines were built as marine engines and produced double to power outoutas a Yanmar marine engine.

I agree about the lower combustion temps, but that's only one part of the long term reliability equation. There are other parts to it, such as increased wear on internal engine moving parts as well as drivetrain parts (due to higher power output), and more wear on the turbocharger itself (when pushing stock one). Yanmar marine engines had a number of modifications to help it cope with higher power output.

Another thing to consider about higher boost is that it usually comes with turning up the fuel. And burning more fuel rarely results in better fuel economy (unless the engine was severely underpowered for the vehicle to begin with, which is not the case with the HDJ80)
 
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But even then, i still have a very hard time believing numbers like this. Not only based on my own personal (rather extensive) experience with these trucks/engines, but also Toyota's own numbers.

For 1995-1997 trucks, with 24V TD and MT original claimed highway fuel consumption by Toyota was 11.2L/100KM. Which translates to 21 US MPG.
This claimed number would be under IDEAL test conditions, brand new vehicle, no modifications and running street/highway tires. These conditions are not realistic for 99.99% of 80-series owners out there, and i have NEVER seen a vehicle (ANY vehicle) from that era achieve their manufacturers fuel consumption claimed numbers in real world. So when i see people claiming 20% better fuel economy (25MPG) out of these trucks when they're 30 years old, lifted, overweight and riding on 35" mud terrains, you can see where my skepticism comes from...

And another point i brought up earlier - Toyota's claimed highway MPG numbers for the US 1997 FZJ80 were 15MPG, which makes this a pretty consistent number considering 40% less energy density for gasoline (in lab environment).
with respect, non of this actually means anything though. People get what they get, as long as there doing there sums right.
 

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