Hey there, I've used the forum for quite some time, but am new to posting. Great site, has been a lot of help. I have an 88 FJ62 that I am looking at converting to diesel. I am looking for real world fuel economy for a 12HT engine. I am waffling between the 5-speed or the A440 auto trans. I already have the A440 in my 62 (I know it is a different trans for the diesel) and I like the way it works, and I have heard the diesel version has the same ratios, and it seems a good match to a lower revving diesel. Any real world numbers would be a big help, either from the 5-speed or the auto. Thanks
12HT Fuel Mileage / Economy
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I, too, am looking at this option for when my 3FE craps out. You may get better results on this inquiry over in the diesel section...
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Downey
SILVER Star
I've had my one and only Diesel, and don't need another one, (although I do recognize the popularity of them in recent years). My diesel did not get particularly great milage, and today diesel fuel cost more than gas, so I'm still questioning the wisdom???
On the other hand I never owned a Chevy V8 "Chevota" that didn't get considerably better milage than the Toyota 6 cyl. (yet I have read on this forum where some did not get great milage with their Chevotas??.
We do have a big 8.0 GM V8 gasoline engine in our new GMC stake bed that gets considerably better mpg than the big 460 c.i. Ford engine in our last stake bed.
On the other hand I never owned a Chevy V8 "Chevota" that didn't get considerably better milage than the Toyota 6 cyl. (yet I have read on this forum where some did not get great milage with their Chevotas??.
We do have a big 8.0 GM V8 gasoline engine in our new GMC stake bed that gets considerably better mpg than the big 460 c.i. Ford engine in our last stake bed.
Tapage
Club 4X4 Panamá
In my diesel world you get les km/g in a uto turbo diesel than in a manual turbo diesel .. and it's sure because you can get much from a turbo diesel at lower rpm if you drive it pretty gentle ..
Out of the conversion when my 60 was stock I could get 36 km/g from she ( Tencha )
Out of the conversion when my 60 was stock I could get 36 km/g from she ( Tencha )
I only had a HJ61 for a few weeks, but in that time it seemed to be about 23-24 mpg imperial.
That was a mix of highway and city driving and I almost always had little play in the dirt 3-4 times a week.
It was a 5sp with 300000klms in very good form.
The characteristics of a good 12HT kind of make you forget about the price of diesel.
Having driven one manual 12HT and a couple of autos,I am a fan of the manual
I think the 12HT goes better with some careful gear changing
However they are getting scarce and it would be worth getting the price of a later 1HZ/1HD T.
Its easier to get parts in north america for these and the supply will go on for many years.
Toyota have very few parts left for 12HT except regular maintenance items. Rebuild kits are still available from aftermarket suppliers
That was a mix of highway and city driving and I almost always had little play in the dirt 3-4 times a week.
It was a 5sp with 300000klms in very good form.
The characteristics of a good 12HT kind of make you forget about the price of diesel.
Having driven one manual 12HT and a couple of autos,I am a fan of the manual
I think the 12HT goes better with some careful gear changing
However they are getting scarce and it would be worth getting the price of a later 1HZ/1HD T.
Its easier to get parts in north america for these and the supply will go on for many years.
Toyota have very few parts left for 12HT except regular maintenance items. Rebuild kits are still available from aftermarket suppliers
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I've had my auto HJ61 for a year now. I consistently return 9km/litre in a mixture of city, highway and a bit of offroad driving. That's about 22mpg (US). Fuel consumption in the auto is highly dependent on whether the torque converter is locked up, so highway fuel consumption is very similar between manual and auto. Best consumption was just more than 10km/litre cruising at 105kmph (just after I had injectors redone). Worst I've returned is 6km/litre in 600kms of heavy sand driving. Constant highway driving @ 110kmph (that's fully loaded, with roofrack) also returned 9km/litre.
I've had a 12H-T conversion for close to a year now. Fuel economy is something that I have struggled with. I get about 16-17 MPG US with a 5-speed manual and mixed city/highway. I't doesn't really seem to improve with straight highway driving.
I've had the injectors done. That increased power, but not really economy (for me).
It's fun to drive now. I tend to get my foot in it sometimes. People drive really fast around here. Sometimes I feel like I'll get run over if I don't.
For what it's worth.
I've had the injectors done. That increased power, but not really economy (for me).
It's fun to drive now. I tend to get my foot in it sometimes. People drive really fast around here. Sometimes I feel like I'll get run over if I don't.
For what it's worth.
I've had a 12H-T conversion for close to a year now. Fuel economy is something that I have struggled with. I get about 16-17 MPG US with a 5-speed manual and mixed city/highway. I't doesn't really seem to improve with straight highway driving.
I've had the injectors done. That increased power, but not really economy (for me).
It's fun to drive now. I tend to get my foot in it sometimes. People drive really fast around here. Sometimes I feel like I'll get run over if I don't.
For what it's worth.
Crap. That's not great...I had thought that the 12H-T got better mileage than that.
Still, good to hear that it's a fun drive!!
I've been operating on the assumption that there is still something wrong with my engine. It sounds like most 12H-T owners get low 20's.
Deffinitely fun to drive. 135 diesel HP is way more than 135 gas HP. Still no race car, but respectable for a 5200 lb. metal box.
Does fiddling with the boost on the turbo change anything?
