It has bottom end bearing issues that need to be fixed if it has not.
Which engine? (2 Viewers)
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I'm amazed that chassis handles 10,000 lbs. You must be a very careful driver to avoid suspension and axle problems. The low engine power might just be your saving grace here.
I'm a fan of Cummins engines and while a 5.9 Cummins would handle the job in style I feel it would be a poor fit as your vehicle does not have the cooling capacity and the rest of the drivetrain would become a fuse for the power.
I'm a fan of Cummins engines and while a 5.9 Cummins would handle the job in style I feel it would be a poor fit as your vehicle does not have the cooling capacity and the rest of the drivetrain would become a fuse for the power.
rideglobally
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I am at the research stage so I am considering most options but trying to stay Toyota. I am also looking into H151f transmission. Not sure how much modifications is needed, I am also trying to figure out if my h55 can handle this kind of power.thx
rideglobally
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It is fairly well accepted you can squeeze a little more power out of a 1HZ than 1HDT, but not by much. And at the those power levels the inherent weakness and cooling issues of the fragile and complex 1HZ head will show themselves. Overheating, Cracked heads and cracked pistons are the rule at high power levels and this will be compounded by a heavy load - everything needs a much higher build standard with heavy loads, look at the hp/kg of a semi engine. 1HZ are only reliable NA, and even then a stock 1HD-FTE will have more miles in it due to it always having spotless oil (unlike the instant tar the 1HZ generates). FTE pump and injectors last at least twice the distance as 1HZ too - I’d wager a 1HZ pump will fail before the electronics in an FTE play up. The only advantage a 1HZ has is coping with bad fuel but a decent filter setup goes a fair way to helping
But also the worst option. You can’t fix the BEB issue - only keep replacing them. It’s an inherent design floor from the piston pulses. And it’s most gutless stock with the least power potential
Your decision is really 1HDFT or 1HDFE. Why bother going to all that effort to not put in the best of the options - given that they all fit in the same hole.
Putting aside the questions people have raised already it depends on what your preference is.
a 1HDFT with a tickled turbo, 3 inch exhaust, fresh injectors and maybe intercooled would be a significant upgrade. This also retains a fully mechanical injection system if that's important to you.
A 1HDFTE with the above done to it and maybe Unichip system will give you more power and selectable maps. The slight downside percieved by some is that these run an ECU (it's caveman tech compared to modern vechiles) which could be a failure point.
Also bare in mind that the FT is comparatively rare, only being in production for a few years as the transition from the 1HDT to 1HDFTE. I have no proof but i suspect Toyota used the 1KZTE as the testing ground for its electronic injection and then moved it over to the 1HDFTE when it was ready. The FT and the FTE share a lot of parts but things might get harder to find.
Also if no one has mentioned it the input shaft on a H55F behind a 12HT is coarse - 6 splines (same as an F/2F) and the 1H* engines need a 30 spline input, and obviously a different bellhousing.
Putting aside the questions people have raised already it depends on what your preference is.
a 1HDFT with a tickled turbo, 3 inch exhaust, fresh injectors and maybe intercooled would be a significant upgrade. This also retains a fully mechanical injection system if that's important to you.
A 1HDFTE with the above done to it and maybe Unichip system will give you more power and selectable maps. The slight downside percieved by some is that these run an ECU (it's caveman tech compared to modern vechiles) which could be a failure point.
Also bare in mind that the FT is comparatively rare, only being in production for a few years as the transition from the 1HDT to 1HDFTE. I have no proof but i suspect Toyota used the 1KZTE as the testing ground for its electronic injection and then moved it over to the 1HDFTE when it was ready. The FT and the FTE share a lot of parts but things might get harder to find.
Also if no one has mentioned it the input shaft on a H55F behind a 12HT is coarse - 6 splines (same as an F/2F) and the 1H* engines need a 30 spline input, and obviously a different bellhousing.
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H15* series will handle the power better.
Staying Toyota diesel 1VD-FTV has the most power potential but FTE will be the most reliable
If he's worried about complexity then a 1VD is probably a bridge too far as well.
This is a grouse discussion!
The effort ridge has put into the the body justifies a good long think for a new engine.
Impressive the 12ht could handle it.
The hz output shaft would be a weak spot, heard of folks stripping it, more than once.
Yes , true about the hz head but it would be possible to get another at least in remote Africa. Ecu's would be another story.
But then any of the hd gear boxes would be a nice upgrade.
Also would be difficult to service electronic injectors remote. Kind of assuming money is not the issue here as electronic injectors cost way more to service.
Another point is that cummins really did make Trucks, with a capital T. Whilst we are in a Toyota love site, Cummins is often referred to in reverence by diesel specialist.
Totally understand a preference to toyota tho.
The effort ridge has put into the the body justifies a good long think for a new engine.
Impressive the 12ht could handle it.
The hz output shaft would be a weak spot, heard of folks stripping it, more than once.
Yes , true about the hz head but it would be possible to get another at least in remote Africa. Ecu's would be another story.
But then any of the hd gear boxes would be a nice upgrade.
Also would be difficult to service electronic injectors remote. Kind of assuming money is not the issue here as electronic injectors cost way more to service.
Another point is that cummins really did make Trucks, with a capital T. Whilst we are in a Toyota love site, Cummins is often referred to in reverence by diesel specialist.
Totally understand a preference to toyota tho.
Something else to point out is that there are lots of 1H* motors in 40 series chassis cutting about. It's been done lots of times and its very well documented. There are OEM parts for mating the H55F to all of 1H* engines since the combo came in the 70 series.
Most of the other options are uncharted territory (somewhat). A 1VD is a big old lump - partly why the 70series chassis and body changed with its introduction. I doubt it would fit in a 40 without a body lift and other stuff. Same with a 6BT, sure it's probably been done but not as simple as a 1H* &H55F. That 40 with a 3208 looked like a ton of work.
Given the wheelbase of that truck he's not limited to a H55F though, so the H boxes are an option. 1 type is stronger than the other, can't remember exactly.
Also don't be suckered in by all sorts of nice engines in what appear to be 40s in Australia - lots of them are built on 80 series chassis.
Most of the other options are uncharted territory (somewhat). A 1VD is a big old lump - partly why the 70series chassis and body changed with its introduction. I doubt it would fit in a 40 without a body lift and other stuff. Same with a 6BT, sure it's probably been done but not as simple as a 1H* &H55F. That 40 with a 3208 looked like a ton of work.
Given the wheelbase of that truck he's not limited to a H55F though, so the H boxes are an option. 1 type is stronger than the other, can't remember exactly.
Also don't be suckered in by all sorts of nice engines in what appear to be 40s in Australia - lots of them are built on 80 series chassis.
Yes, easy is good. Bet ridge would not have minded banging another 12ht in there if parts were not hard to find.
Just a side note on the 12ht, last I looked at hj61s on carsales , there actually was quite a few good looking 12ht's on the market., well, at least a dozen. All had a very healthy price for their age and all had at least over 500k kms, not many engines stand out like that. The sellers all knew what they had.
Two of them and you won't have to talk no more!
Two of them and you won't have to talk no more!
All this is way outside my wheelhouse, I am always impressed by the free exchange of information on this forum.
yeah, nothing like mud!
I've been looking for a 1HDFT for several years here in NZ, basically none have turned up. Current rates ($NZD)
1HZ - $2-3K. Most have insanely high km.
1HDT - From about $4.5k. Most look rooted.
1HDFT - North of $6k
1HDFTE - North of $10k.
12HT - Haven't seen one out of a truck, seen a few 60s with them, anywhere from 12K depending on how much rust.
Add about 20% if being sold by a wrecker.
several years! patient fellow , ahh money . My finances simply force me to live in the 2h realm, being slow suits me fine, at least I can pull some weight at least. Your coin is virtually same here.
Or, just be satisfied with what you have and take the slow road. You are over-landing and in no rush. Soak it in as you go. Isn’t that the purpose of overlanding, slowing it down, no deadlines, get there when we get there? You can keep $ in the bank. My take is you’re pissing your money away staying simple Toyota. It’s a 45, I get it but let’s be realistic it’s an RV as well. Get some Barry White playing.
That's the one!!!
