Why diesel swap?

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Nov 10, 2006
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Location
Warsaw, Poland
I see more and more people swapping the 1FZ-FE for a diesel (usually with a manual trans) and I am just wondering why?

I live in a place where probably 80% of vehicles are diesels and the 80-series is no exception. I am sure that even more than 80% are 1hd-t or 1hd-ft. The same with the 100 series with the 1hd-fte.

So here are my observations from a land of diesel (Europe) but I will try to narrow it down to the 80 series.

- the diesel stinks when compared to the 1-fz-fe for obvious reasons.
- there is no gain in performance. The 1FZ has torque of a diesel and this torque is available from low rpms, but an advantage of the 1FZ is power and instant reaction when you press the pedal to the floor.
- you can push the gssoline engine to the redline all day and the truck is happy. Gasoline engines are not afraid of redline.
- gasoline engine has low vibrations and a much nicer sound than the clunk of a diesel
- in many countries. for example Germany, you can drive in the cities if you have a green sticker. Otherwise cameras catch you, check the plate number, check the vehicle model and you get a fine. Gasoline engines get a green sticker hands down and even the 1fz does conform with emissions standards. Most, if not all, old diesels are banned. New diesels have DPF filters and other stuff but they are unreliable as hell, that's another story.
- the 1fz is overbuilt like a diesel and I am sure it will achieve high mileage. An engine as fat as a diesel with a low compression (around 10:1) equals high reliability, high MTBF
- the 1fz is as simple as an engine can get. No turbo, easy access to all the components, chain-driven timing, low pressures everywhere.
- the 1fz parts are cheap and available everywhere round the corner, not the case with diesels.

So that's as far as engine goes, now the tranny.

- an auto is simple and easy to use. Much nicer than a manual
- a few hours behind the steering wheel let you get a feel of the auto tranny so you can shift gears with your foot. You simply learn when the truck will downshift and upshift
- if you are a control freak, you can buy a simple electronic device (I have a source for them, $200) which lets you ovverride the tranny ECU and manually shift gears, lock the torque converter, use some half-automatic shifting patterns etc.
- the auto tranny is easier for the components during off road as there is no 1:1 direct power output so when your spinning wheels suddenly gains traction the impact is dampened by the tranny. On manual transmissions birf and axles break much more often and on rigs with relatively small wheels (33-35").



OK I see some advantages of the diesel+manual swap:

- better mileage. But does the mileage difference (20-30%) justify such an expense?
- better control for control freaks, though IMHO there is no advantage
- owning something special, being proud of being different. Feeling like a guru because all the crowd has gas+auto and I have diesel+manual.


I am aware that subjective preferences and dreams are an important factor and we like when our dreams come true, but are there any realistic, scientific, objective reasons to ditch the 1fz for a diesel? Mileage is one, but hardly justifiable. Am I missing something?
 
1HD-T's rev out just fine all the way to 4200 and idle smoothly and quietly.

For me it isn't about mileage. It's about range and simplicity. A manual pump diesel requires one wire to run and can go a lot farther than a gas engine can on the same amount of fuel. Not to mention it will last longer (there are more than a few 1HD-T 80-Series cruisers around with more than 1 million km).
 
I think his point is in regards to gasser 80s dropping the 1fz for a diesel.

OP - Probably your 3rd reason is why many do the swap. A little, "grass is greener" thing, and "want what I can't have" thing too.
 
For me it isn't about mileage. It's about range and simplicity. A manual pump diesel requires one wire to run and can go a lot farther than a gas engine can on the same amount of fuel. Not to mention it will last longer (there are more than a few 1HD-T 80-Series cruisers around with more than 1 million km).

All you guys flaunting your big mileage numbers when in realty your 1 million kilometers is only like 50 miles or something. :flipoff2:
Yes, I am being snarky because I never had an option to drive a stinky diesel 80.:moon:
 
Seems like at high miles the petrol rigs always need the head gaskets done and the diesels always need the crankshaft bearings done. Seems like a reliability wash there with no advantage to either side. The diesels will run in the water, and the gas jobs will start in the cold, so another wash there. I don't understand the reasoning behind doing the diesel conversions, but there sure are a lot of them done so there must be something to it.

I have been told that the diesels make less horsepower and more torque vs the gassers so maybe that's an advantage? Both are pretty tolerant of crappy fuel, both have decent power with factory tires and gears, both have poor fuel milage. I don't see spending the dough to replace my 1FZ, I'd rather rebuild it and put on some nitrous for any (infrequent) power boost I may want.
 
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Seems like at high miles the petrol rigs always need the head gaskets done and the diesels always need the crankshaft bearings done. Seems like a reliability wash there with no advantage to either side. The diesels will run in the water, and the gas jobs will start in the cold, so another wash there. I don't understand the reasoning behind doing the diesel conversions, but there sure are a lot of them done so there must be something to it.

The big end bearings are a one-time job (that costs <$150 and takes ~4 hours) that doesn't need to be done on the later HD-FT motors. I've started my 1HD-T at -40C not plugged in overnight. With that said the diesel is not ideal in the cold, it takes a looong time to warm up.
 
Not a swap story, but I went with diesel for fuel versitility: Used veggie oil, biodiesel, and hydraulic oil.
I will be swapping a manual transmission in for the accomplishment of the project, and I find automatics extremely boring to drive (I drive 18spds for work).
 
I agree for both sides b"coz I have BOTH 91 3fe and 91 2lte ..;)

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Sorry I uploaded twice.. my bad. first timer though.
 
I love my smokey, stinky diesel. About the only thing I hate about it is its smokey and stinks. :flipoff2:
 
the reasons i want diesel are:

1: range on a single tank
2: miles per dollar
3: turbo can increase #1 and #2 if i keep my foot out of it, unlike a gasser.
4: sense of accomplishment and ownership
5: we don't have the diesels here.
 
Oh look its this thread again.

None of that s*** holds water here so...

Different strokes for different folks.

Really seems like you're just here to tell us how s*** diesels are.
 
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:clap:
 
if I lived in Poland, I would probably think differently about diesel, I don't know

I used to live in Germany, and wasn't a fan of diesel while living there - and haven't been convinced to become more of a fan in >20 years of driving rental diesels when I visited over there :meh:

I won't get a diesel in the US - the fuel is dirtier than in Europe, and it doesn't make economic sense here in the US, either, given that availability is generally low in those unpopulated areas where you might want it for range

did I mention I wheeled behind a diesel 80 on Golden Spike in Moab for an entire day :mad: - it's not a fragrance, it STINKS :bang: (and this was not my only experience wheeling with diesels :rolleyes: by now, I make sure I am ahead of them on the trail :p)
 
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I'd like to & will end up doing a turbo diesel swap:

1) power!

Preferably a 12v cummins which is easily upgradeable to 300hp / 650ft/lb

& Screw a manual shift tranny. Not in Houston traffic.
 
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I drive a modern diesel car and I love it. Why? The power (torque actually). It just puts a nice smile on my face every time I floor it.
Fuel economy is not bad, but when you factor in the cost of diesel fuel (higher than gasoline where I live) and the cost of DEF, there is not much of a difference in dollar/mile ratio.

My wife constantly complains our TLC has no power. She wishes for more passing power on the freeway and even on the streets.
This is where the diesel engine comes in. It's tunable, you can squeeze more power out of it.
None of that can happen to the gasoline engine, unless you turbo charge it.
Low RPM power when off roading is always a good plus.
2-5 mpg on the trail in the middle of nowhere is also a plus.
The black soot and smell is not a big factor with me. They don't all do that, unless you constantly floor it.
I love the "clack, clack, clack" sound the old diesels make.

Would I reposer my TLC with a diesel? NO!
It makes no financial sense to me. I would however buy one that was already converted (or a factory diesel) for decent price. The price of a conversion will always be higher than what you can buy already converted.
 
if I lived in Poland, I would probably think differently about diesel, I don't know

I used to live in Germany, and wasn't a fan of diesel while living there - and haven't been convinced to become more of a fan in >20 years of driving rental diesels when I visited over there :meh:

I won't get a diesel in the US - the fuel is dirtier than in Europe, and it doesn't make economic sense here in the US, either, given that availability is generally low in those unpopulated areas where you might want it for range

did I mention I wheeled behind a diesel 80 on Golden Spike in Moab for an entire day :mad: - it's not a fragrance, it STINKS :bang: (and this was not my only experience wheeling with diesels :rolleyes: by now, I make sure I am ahead of them on the trail :p)

Sometimes out on a trail we have 10-15 1HD-T's crawling along one after the other. ...The only good position is upwind..
 
Isn't diesel generally considered better for towing? My build is eons from power train choices but today I am planning diesel to tow a small camper. That and because @Arya Ebrahimi 's kit isn't finished yet!
 
I'd like to & will end up doing a turbo diesel swap:

1) power!

Preferably a 12v cummins which is easily upgradeable to 300hp / 650ft/lb

& Screw a manual shift tranny. Not in Houston traffic.

Pretty sure that kind of power on an early 6bt is somewhat dependent on the use of a rather large intercooler such as the one on my son's 97 Dodge with this setup. That IC is WAY too big to ever fit in an 80. John
 

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