Thinking of a 4bt or 6bt swap?? help

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I tend to be impulsive, I tend to interrupt.... When i saw this thread, I had been away from MUD for almost 5 years. Gotten into diesels and away from the fold.... I fully understand this stuff about the 6at was what is called in the cyberworld a HIJACK. I want to appologize to the 6bt and 4bt people that I am sorry I busted into their thread and ranted about the 6at. I was out of line and that's what a hijack is. When I want to extol the virtues of something I like from now on, I will start a new thread........
 
Don't forget that though you may get 20mpg diesel is now dang near $1/gal more than gas, at least around here.

Truer words have never been said.

IMO The benefits of a diesel are: range and simplicity (depending on platform)

FWIW, lot of 4bt swapped rigs end up for sale.
 
I tend to be impulsive, I tend to interrupt.... When i saw this thread, I had been away from MUD for almost 5 years. Gotten into diesels and away from the fold.... I fully understand this stuff about the 6at was what is called in the cyberworld a HIJACK. I want to appologize to the 6bt and 4bt people that I am sorry I busted into their thread and ranted about the 6at. I was out of line and that's what a hijack is. When I want to extol the virtues of something I like from now on, I will start a new thread........

Didn't seem out of line to me at all.

The Onan diesels Cummins called the "A series" for a short time after Cummins bought Onan have a poor reputation. You seem really happy with yours, which is great.
 
IMO The benefits of a diesel are: range and simplicity (depending on platform)

FWIW, lot of 4bt swapped rigs end up for sale.

I have thought long and hard about your second point ( before I started my conversion ) and my conclusion was that expectations must not have been set correctly either prior to the conversion or prior to the purchase of an already converted truck. Cummins 4/6B(t) motors tend to be loud, they produce a bunch of vibrations, they require a bunch of lift to make work in the LC platform. If you are thinking about a swap, you need to be prepared to face those downsides. If not, then it will likely be up for sale.

FWIW, I see a lot of V8 conversion trucks for sale as well :rolleyes:

Didn't seem out of line to me at all.

The Onan diesels Cummins called the "A series" for a short time after Cummins bought Onan have a poor reputation. You seem really happy with yours, which is great.

I agree, didn't seem out of line to me. Good info man, thanks!
 
Thanks guys. I still want to start a thread about these engines. All 3 of mine start well and run really smooth. But at 120 hp, they certainly aren't for everyone. Ok, off to work.......
 
I know i will be going with the 6bt. I need to see which tranny and trasfercase. I have a ome 2.5 lift. i ned to lift more, but i i dont want to do a spring over.
 
I know i will be going with the 6bt. I need to see which tranny and trasfercase. I have a ome 2.5 lift. i ned to lift more, but i i dont want to do a spring over.

I have never heard of one of these swaps in a SUA truck but go for it and document it.
If you move your front axle forward it should give you more clearance on the front axle and oil pan.

6BT going to be stock power level?
 
Truer words have never been said.

IMO The benefits of a diesel are: range and simplicity (depending on platform)

FWIW, lot of 4bt swapped rigs end up for sale.

Diesel might be more expensive, but current overpricing doesnt even come close to negating the savings in fuel. To make math easy, if regular is 3.00 / gal and diesel is 4.00 / gal, thats a 33% increase in price over reg. (im currently paying 3.80 and regular is 3.30, so im being very liberal in my numbers) any diesel you stick in there will get > 33% increase in mpg. More realistically, 25 mpg is upward of 100% greater mpg, so until diesel is 2x the cost of regular the "diesel costs more" point is moot.

Im sure some people sell their 4bt builds for being disappointed (I personally have no idea why, but can certainly entertain the possibility of overexpectation leading to disappointment), but a lot of people I know (including myself) sell their builds to build another. Its not that we dont like what we built, but we love the building and apply what we learn to the next one. And/or move on to a different starting platform. If money (funding), space (wish I had a warehouse filled with lifts amd tools but I dont), and time (maintaining, modifying, and fixing problems) werent issues then id have dozens of builds strewn about and my only dilemma would be which one to drive.
 
Diesel might be more expensive, but current overpricing doesnt even come close to negating the savings in fuel. To make math easy, if regular is 3.00 / gal and diesel is 4.00 / gal, thats a 33% increase in price over reg. (im currently paying 3.80 and regular is 3.30, so im being very liberal in my numbers) any diesel you stick in there will get > 33% increase in mpg. More realistically, 25 mpg is upward of 100% greater mpg, so until diesel is 2x the cost of regular the "diesel costs more" point is moot.

But if you are talking about cost savings after a diesel swap, it takes a long time for it to add up. Let's say you drive your cruiser 20k miles a year, which is waaaayyyy more than most 20+yr old cruiser owners do. Not all...but most.

Gasoline 3FE
20,000miles/12mpg=1666.67 gallons of fuel x $3.40=~$5600 a year
Cummins 4BT
20,000miles/20mpg=1000 gal fuel x $4= $4000 a year.

My 3FE on my older 62 was getting 14-15mpg pretty frequently, but most on the road get less. And it seems like most diesel guys are getting about 20mpg on average depending on driving style, terrain, and tires/gearing.

$1600 a year is pretty good! But that will take 5yrs just to recoup the added costs of a $1OK engine swap vs a 2F or 3FE rebuild of a couple thou or so. Most likely it will take longer than that time frame to recoup, purely from fuel savings. The money savings argument is valid, but only over the long term. And it seems like $10k soup to nuts on a Cummins swap is probably the minimum if doing all the work yourself, correct (to those who have done it)?

The quicker, more tangible difference is definitely range. And mechanical diesels are legendary for reliability, ease of repair, etc.
 
Don't do a diesel swap, or any engine swap for that matter, for better mileage alone. Hell, you should forget about it completely; I'd like to put an Isuzu 4BD1T mated to an H55, (or equivalent trans.), into my 60 just to see if I could do it, and to have a unique LandCruiser! The extended range and increased power output are motivators, but in the end, if your crunching numbers to find out how long it will take to pay for its' self, then maybe you don't really need to do a swap at all.

You will not be saving any money by doing an engine swap, its gonna cost a LOT of money, and in the grand scheme of things the only reason I think anyone should consider it is for the novelty of having that given engine. This is not to say that there is anything wrong with finding out how long it would take for fuel cost savings to pay for the swap, just that it shouldn't be your main motivation.

My main motivation to looking into it myself is that I'm looking down the road and deciding how I want to use my truck in the future, and I'm planing out how I should build it. I'm 19 now, and I plan on keeping my 60 until I kick the bucket, and would like to be able to have a capable truck that can get me anywhere I want to go. I don't have any interest in the Rubicon, but I would like to get out into the middle of nowhere and cast a line out where nobody has fly-fished before. Basically, I'm trying to build my idea of the perfect retirement truck before I'm 25; cause the longer you have to enjoy it the better right? :D
 
But if you are talking about cost savings after a diesel swap, it takes a long time for it to add up. Let's say you drive your cruiser 20k miles a year, which is waaaayyyy more than most 20+yr old cruiser owners do. Not all...but most.

Gasoline 3FE
20,000miles/12mpg=1666.67 gallons of fuel x $3.40=~$5600 a year
Cummins 4BT
20,000miles/20mpg=1000 gal fuel x $4= $4000 a year.

My 3FE on my older 62 was getting 14-15mpg pretty frequently, but most on the road get less. And it seems like most diesel guys are getting about 20mpg on average depending on driving style, terrain, and tires/gearing.

$1600 a year is pretty good! But that will take 5yrs just to recoup the added costs of a $1OK engine swap vs a 2F or 3FE rebuild of a couple thou or so. Most likely it will take longer than that time frame to recoup, purely from fuel savings. The money savings argument is valid, but only over the long term. And it seems like $10k soup to nuts on a Cummins swap is probably the minimum if doing all the work yourself, correct (to those who have done it)?

The quicker, more tangible difference is definitely range. And mechanical diesels are legendary for reliability, ease of repair, etc.

i dont want to sound like i'm patronizing in any form, however, everything you said above is in agreement with my first post except for two statistics: - - - (keep in mind i said that diesel swaps have often surpassed ones projected budget/expectations, mostly due to improper/inadequate preparation.)

1) 10k diesel swap. if youre spending 10k on a diesel swap, youre doing it because
a) you want it to remain all toyota
b) you are ill informed/didnt do homework on the options available in the form of swap candidates and their availability/abundance
c) you have copious amounts of money and want to do it your way only
d) all of the above
2) 20 mpg. . . .
a) I average 20 mpg in my 7500 lb pickup truck (its decently setup for mileage, i got 21-23 with small injectors), so 25+ mpg in a 5000 lb landcruiser is not out of the question
b) ive seen first hand an old brick f250 that i built with a 4bt/5 speed achieve 26-27 mpg average with 285's, ported everything, 40 horse injectors, ve pump w/ fuel pin and timing bump, and hx30. that truck weighs 5800#, and is noteworthy that it is turning the factory 8 lug 4x4 gear.

all that being said, ill never say over the internet that someone isnt getting horrible (relatively speaking) mileage with their particular setup. however, i will always cite my personal experience and knowledge gained through said experience to suggest to others what is possible with the right homework/setup. a run of the mill 4bt off craigslist is 1500-2500. an expensive (often p pump) 4bt is 2500-4k. a 4bt can be had for much less if patient enough to find one in a boneyard ( ~5-750 from u-pick, u-pull) or almost free if crafty enough to teardown a bread truck for the motor, and scrap the rest. there are soooooooo many other options out there, aside from the 4bt, that we could talk about for days and still not accurately represent all of the potential swap candidates and how to get them cheaply (isuzu, hercules, 6at, cummins 3.3, perkins). its worth noting, anything IDI will get worse mileage, DI and turbo will net the best overall results.

with the motor cost out of the way, how much is it to finish the job? adapters, wiring (or lack thereof), metal fabbing, fuel lines, misc - - -1k? 2k!? 3k!?!?!? even at 3k (an outrageous figure) we still arent close to the 10k even with the most expensive 4bt candidate. subtract the cost of a 2f rebuild (and the "misewell mods" associated with that) or even more, a 3fe, and we further narrow the gap. you just cant beat the thermal efficiency of a diesel vs a gas motor.




:beer:
 
Don't do a diesel swap, or any engine swap for that matter, for better mileage alone. ****, you should forget about it completely; I'd like to put an Isuzu 4BD1T mated to an H55, (or equivalent trans.), into my 60 just to see if I could do it, and to have a unique LandCruiser! The extended range and increased power output are motivators, but in the end, if your crunching numbers to find out how long it will take to pay for its' self, then maybe you don't really need to do a swap at all.

You will not be saving any money by doing an engine swap, its gonna cost a LOT of money, and in the grand scheme of things the only reason I think anyone should consider it is for the novelty of having that given engine. This is not to say that there is anything wrong with finding out how long it would take for fuel cost savings to pay for the swap, just that it shouldn't be your main motivation.

i couldnt agree more. fuel mileage alone shouldnt be the only motivation for a diesel swap. however, there is a huge gap between driving a gas powered vehicle and a diesel. the gratification of the diesel torque (most often 2x its hp) is unmatched by any gasser. combine that with its superior efficiency, and we are starting to build a case for the swap. combine those variables with a blown 2f, and its lookin much more promising. combine all those variables with the desire for 300hp, and theres only one option.

and then of course, theres the ability to get a diesel for cheap that is always a game changer, especially when combined with above said variables.
 
i couldnt agree more. fuel mileage alone shouldnt be the only motivation for a diesel swap. however, there is a huge gap between driving a gas powered vehicle and a diesel. the gratification of the diesel torque (most often 2x its hp) is unmatched by any gasser. combine that with its superior efficiency, and we are starting to build a case for the swap. combine those variables with a blown 2f, and its lookin much more promising. combine all those variables with the desire for 300hp, and theres only one option.

and then of course, theres the ability to get a diesel for cheap that is always a game changer, especially when combined with above said variables.

I guess I should have read the first post. ;)
 
A lot of things here I agree with and disagree with. GLTHFJ60 was spot on with his last comment. I would recommend anyone thinking of doing a 4bt swap see one run in person first. And btw, my 4bt is bone stock for fuel economy, and Ive never seen 25 mpg. In my case, I had to get a new engine, and the benefits of a diesel were appealing. If I had the money I would have gone Toyota diesel.
 
i dont want to sound like i'm patronizing in any form, however, everything you said above is in agreement with my first post except for two statistics: - - - (keep in mind i said that diesel swaps have often surpassed ones projected budget/expectations, mostly due to improper/inadequate preparation.)

1) 10k diesel swap. if youre spending 10k on a diesel swap, youre doing it because
a) you want it to remain all toyota
b) you are ill informed/didnt do homework on the options available in the form of swap candidates and their availability/abundance
c) you have copious amounts of money and want to do it your way only
d) all of the above

We could argue cost all day long, with me stating that it will cost somewhere near $10k all said and done, and done right.

My real costs:

- Running 4BT with Hydroboost and fluid filled motor mounts - $3000
- Rebuild kit - $700
- New Turbo - $350
- Injection Pump work - $150
- Injector spring and pin - $100
- Dodge adapter + bellhousing, NV5600 flywheel, south bend clutch, Dodge NV4500HD transmission, Dana300 indexing ring and input gear - $3000
- Dana300 - $100
- Rear driveshaft - $100
- Fluids - $200
- Lines, throttle cable, hoses - $200

I know there is stuff I've forgotten and the above total is $7800. These numbers are fresh as I've just finished my swap in the past month. I did not keep it all Toyota, nor did I do 'my way only'. Even if $10k is generous, that's a good ballpark.

Not a dime spent was due to poor planning, but due to calculated decisions, aimed at making my truck as much of a pleasure to drive as possible.
 
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We could argue cost all day long, with me stating that it will cost somewhere near $10k all said and done, and done right.

My real costs:

- Running 4BT with Hydroboost and fluid filled motor mounts - $3000
- Rebuild kit - $700
- New Turbo - $350
- Injection Pump work - $150
- Injector spring and pin - $100
- Dodge adapter + bellhousing, NV5600 flywheel, south bend clutch, Dodge NV4500HD transmission, Dana300 indexing ring and input gear - $3000
- Dana300 - $100
- Rear driveshaft - $100
- Fluids - $200
- Lines, throttle cable, hoses - $200

I know there is stuff I've forgotten and the above total is $7800. These numbers are fresh as I've just finished my swap in the past month. I did not keep it all Toyota, nor did I do 'my way only'. Even if $10k is generous, that's a good ballpark.

Not a dime spent was due to poor planning, but due to calculated decisions, aimed at making my truck as much of a pleasure to drive as possible.

so, i can admit that i shouldnt have broken it down quite like i did. everyones circumstances and conditions are different. i.e. parts availability (or lack thereof), working space (or lack thereof), working conditions, time frame to collect parts, and knowledge of whats out there and how to get it.

all that said, i can agree that 10k is a good ballpark number, especially since overestimating is the responsible thing to do anyway. i think the point i was trying to make is that, while 10k might be a good ballpark guess, the same exact thing can be done for 5k or even less with the proper resources and time.

like you said, we can argue all day about the numbers and what shoulda or coulda been done to save money, even with your list. i dont want to disrespect any of your decisions or their outcomes, so i think ive said my piece. if anyone is further interested in the options that are out there for parts collection id be glad to make some suggestions.
 
A lot of things here I agree with and disagree with. GLTHFJ60 was spot on with his last comment. I would recommend anyone thinking of doing a 4bt swap see one run in person first. And btw, my 4bt is bone stock for fuel economy, and Ive never seen 25 mpg. In my case, I had to get a new engine, and the benefits of a diesel were appealing. If I had the money I would have gone Toyota diesel.

bone stock is not the best formula for maximum fuel economy. ported everything, boost tube to uncork #4, timing adjustment, good quality mild injectors (~40), and a mild fuel pin (for ve pump) will net you close-to-maximum mileage capability.

i understand paying someone to do all that is expensive. but doing all of the porting and intake mods yourself is virtually free with the cost of a die grinder and a small burr assortment. so that leaves the other goodies, which would be <1k. thats a small price to pay for better mileage with a much better driving experience. that will easily net you >10% efficiency boost.
 
I'm looking in to doing a 4bt in to a land cruiser fj80 i was hearing that you want to go with the transmission that came with the 4bt. I am stuck though before i start in on this project i would like the cruiser to switch between 4x4 an 2x4 and i would like to keep it as much stock as possible. If i change out the transfer case would i have a problem with the gearing in the axis . I would also like to race it up in the future but right know i would like to just have it as a rolling reliable project so please help
 
I'm looking in to doing a 4bt in to a land cruiser fj80 i was hearing that you want to go with the transmission that came with the 4bt. I am stuck though before i start in on this project i would like the cruiser to switch between 4x4 an 2x4 and i would like to keep it as much stock as possible. If i change out the transfer case would i have a problem with the gearing in the axis . I would also like to race it up in the future but right know i would like to just have it as a rolling reliable project so please help

You need an Advance Adapter and a split t-case from a 60 or 62 to keep it as stock as possible and switch between 2 and 4 WD. a NV4500 transmission is also a good upgrade. That's the set up I have in mine and after working out some bugs, I love it. Of course if money isn't an issue then get a Toyota diesel, preferably a 1HD-T. A lot of the guys here can do most of the work themselves and can give you real good advice. I'm not that mechanically savvy, but I've driven virtually all diesels Toyota has made and I know which ones I like to drive.
 

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