Thinking about a diesel swap, veterans, I'm looking for your input...

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I'm still in the very early stages of evaluating this idea, but please bare with me.

Here are my motives:

- I need to do something to lower my overall fuel consumption significantly

- I love my Cruiser and don't really ever see parting with it(it may not always be my DD, but for what it's worth on the general market, I just don't see much value in selling it)

- My 1FZ-FE is burning/leaking a quart of oil every 3,000 miles(smells like a damn two-stroke)

- I need something capable of towing my mini-truck 4+ hours each way on a trailer every couple of months reliably and safely(for out of town 'wheelin trips).

- I was looking at buying a new car, but when I looked at what a new vehicle costs, I got major sticker shock and am re-evaluating(someone once told me "the cheapest vehicle is the one you already own", made me feel a lot better about spending $400 on maintenance this week too).
_______

So, with all that in mind, I'm looking at a diesel/manual tranny swap.

My current MPG is averaging 9-11 depending on the mix of city/highway. So if I am able to get up to 22-28 w/ a diesel I will have cut my consumption of gasoline by over 50%.

I feel that if I do a diesel swap using an Isuzu diesel w/ an NV4500 behind it(chose this combo after some preliminary searching, please feel free to comment on this choice), this combo will tow well as far as powertrain is concerned. I also feel that the stock 80 axles are up to the task assuming proper maintenance, so the only question in my mind is the suspension. If I have to add airbags or air shocks to the rear suspension to deal w/ the task of towing, and it means I don't have to buy a 3/4 ton pickup to tow the pickup, I'm willing to do it. ;) Also, at this point I'd be looking at some sort of adapter to the 80-series T-case to mate it to the tranny. Does anyone know of such a thing? What would my other options be?

Lastly, what do you guys think this thing would cost, assuming low mileage takeouts or rebuilt components and free labor(any machine shop labor or highly skilled labor would need to be counted, but I would be doing the swap myself with a few friends).

Basically if I can do this whole swap and have a nice fresh truck that is suitable to my needs for under say $6k, I think it is very feasible. For those that are going to recommend the econo-box route for fuel consumption reasons, please see my list of needs above that will rule that out rather quickly. Basically what I'm trying to achieve is a 7k# tow rating, 22-28mpg, and a fresh powertrain, not something I see happening in a Honda ;p Oh, and for those wondering about the reason for a manual, well, I've just always wanted one. I also think it would give me a lot more control when towing.

Thanks for reading my long post, I look forward to your constructive input :)

Edit: I knew I forgot something. The topic of brakes! When towing anything significant the trailer would be equipped w/ surge brakes at the very least. I'd prefer to install an electronic brake controller though and use proper trailer brakes.

Ary
 
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I too am looking to go that route, I already have a cummins I-6, and an allision 545at transmission. But I think I want to go with the Allision 1000 6speed.
Unfortuantally I dont think you will beable to do the entire swapp for under 6K
From what you say you are looking for, the Engine will cost around 1K-3K the transmission 1K-2K an adapter for the transfercase.. i donno... 500-1K
then you will need to address the cooling side.. if the engine you get is only an I-4.. it will be too short.. a cummins i-6 is longer than your current I-6. So larger radiator, and electricfans... 1K you also say you want to tow your mini truck.. you might want to look into a mild lift.. 2-4" and maybe a 1" body lift.
that will offset the weight of the newer componets and extra spring in the rear to tow your truck. so thats about another 1K. Then, if you want to go to a nv4500, youll need to cut out a hole in your firewall, and replace your brake pettle with one that includes a clutch.. so ,, you can get one from a junk yard , brake/clutch assy, resivore, and brake booster assyemble (because diesels dont make vacuum).. so thats about 500 bucks. so far this is all with out labor from anyone else... having changed trannys and such.,,you will also have to most likely get your drivelines re sized. donno how much they charge from that.
you can probably get some motormounts fabbed up for about $250.
So your looking somewhere more around $8,000 to $10,000
Then add in any extra fabracation and labor that you cant do or wont do yourself.
-Ron
 

sleeoffroad

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The cheapest vehicle might be the one you own, but not after you need 6-10k to do a swap. I have never done one, but I can guarantee you it is going to be more than you think.

We recently bought a 2000 Dodge diesel 2wd at auction for around $9k. Has 240k miles or so. You would be much better off with a deal like that to tow. Might also get better mileage than the 80.
 
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Why not acquire an original Toyota 4.2 turbo diesel engine? Only place it's not sold is US, but perhaps you could source one from Central or South America more cheaply.
 
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I would never want to tow that much weight with coil springs. It just isn't safe. Buy a used 3/4 ton pickup and be done with it. Why buy new? Also, I don't know about VA, but diesel is running .75-.85 more than regular here right now. When you couple that with the much cheaper cost to get into a gas truck, you may want to look for a big gas motor. Ford and Dodge have both offered V10's recently, and Chevy has the 454 of course. I know on a new Ford the V10 is about a $600 option, but the diesel is about 10 times that much.
 

dclee

 
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I too am looking at this option (see my post in Chit Chat about getting a 300GD diesel G-Wagen). I also thought about dropping something in a 91-92 FJ80 (I am not touching my current FZJ80, it is a purpose built vehicle and will never be used for daily driving). Whatever I end up with, if anything, will be converted to biodiesel and possibly WVO/SVO, so that obviates the higher cost of diesel at the pump. However, I don't have your towing requirements, so your choices will most likely be different than mine (that 3 liter Merc engine is already a dog, don't even talk about putting a trailer behind it...).

Anyway, keep us updated on your plans.
 
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Josh83 has some good points. Considering what it will cost to do the swap and make it work properly, you'd be better off buying a used 3/4 pickup. Diesel is quite a bit more than regular gas these days. In addition, I don't think you'll ever feel comfortable in an 80 towing 7k pounds, new engine/tranny or no. Your options aren't limited to "modded 80" or "new pickup"- IMHO you should seriously consider adding "used pickup" to that list.
 
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I suppose I should have put quotes around the word new. I'm not looking at a new pickup, I'm looking at a "new" pickup(to me). I've been looking at the 99-02 Superduties and the '02 Duramax's(this is my favorite body/engine combo).

Additionally I'm a fulltime college student, and parking a full-size pickup on campus isn't exactly going to be fun. I guess I was hoping I could have the ultimate "do-everything" rig for a minimal investment(compared to another vehicle at ~20k$). I realize it would be a lot of work, but I was hoping it was possible.

BTW, the 7K# is a rough guesstimate, does anyone know what a typical 16' car hauler weighs? The mini-truck is on somewhat of a diet(no bed, fiberglass front fenders, etc), so I don't know that it will weigh in over 4000 lbs.

Ary
 
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Arya,
Towing that much behind an 80 is a pure white nuckle experience above 45mph.
You really need the longer wheel base to be comfy with it.
I to am interested in diesel conversions on 80's.
Veggi thoughts. There is a Wendy's next door to where I work.
Easy refill.
The thought of an 80 farting out the smell of fries is appealing.
Stock HZ or Isuzu is the way I hope to see you go
 

dclee

 
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fzj80kidpen said:
Stock HZ or Isuzu is the way I hope to see you go

I thought about the 1HZ too. Nice engine. But I don't like the rubber belt driven cams.

The older 1HD-T has a chain and no electronics to fail, but I hear they have "big end" problems, which I think means crankshaft bearings?

Oh well, can't have everything...
 
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What about the Chevy 6.2 or 6.5 diesel. The adapters are all available, replacement parts/aftermarket power up parts are all available and im sure alot of qualified people could wrench on it if needed. I think if i went with any other engine that wasnt a toyota, i'd look into the Chevy diesel b/c of the above reasons and alot of guys in OZ have done it. You wouldnt have to go into it totally blind.

Honestly, i hate the thought of my beloved toyota being powered by a chevy but a hopped up 6.2 or 6.5 v8 diesel would be fun, no matter how you cut it.
 
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Brandon, I'll just reply here to your PM, I've been told that the benefits of the Chevy diesels end at the ease of swap. I've been told/read that they're dogs and aside from the fact that they burn diesel, there's not much desirable about them.
 
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Arya Ebrahimi said:
Brandon, I'll just reply here to your PM, I've been told that the benefits of the Chevy diesels end at the ease of swap. I've been told/read that they're dogs and aside from the fact that they burn diesel, there's not much desirable about them.

Thats too bad, wish it wasnt true. Where did you read it from? Weird that marks adapters would make a whole kit if it wasnt truely worth the time. I know white shark is looking into doing a 6.2 or 6.5 chevy diesel seeing as he has a 350 in his truck already. Maybe he knows some more info about this and will chime in.
Have you looked into Cummins 4b or 6b's......dont know if adapters are readily available but as i recall it has been done.
 

jonb96150

 
 
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[
BTW, the 7K# is a rough guesstimate, does anyone know what a typical 16' car hauler weighs? The mini-truck is on somewhat of a diet(no bed, fiberglass front fenders, etc), so I don't know that it will weigh in over 4000 lbs.

My 16' car hauler is about 1800lbs. I also figured 7k for the trailer loaded with the 4runner and all supplies. That is probably a generous estimate. I could probably pare it down to under 6500. My f250 handles it fine except for the 351 c.i. engine struggles on steep grades. So I go slow on steep grades. I still am thinking that I can use the fzj80 to tow that load if I use a weight distributing hitch. And go really slow on steep grades! People will disagree, but the r.o.w. tow ratings are over 7k I believe.
 

tarbe

 
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I would think you could get 20 - 22 with the setup you described (unloaded, not towing). I can't imagine you'd ever see anything near 28.

I would love a setup like you describe. If my 1FZFE just blew up one day, I'd seriously consider it. But not for regular towing of 6,000 lbs or more. That 112 inch wheelbase is gonna have the tail wagging the dog.

Hey - may you can put a custom 5th wheel on the roof! :)
 
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I'm still trying to take in what everyone is saying and weigh it out in my mind. One thing that I do want to comment on is the price of diesel. This is something I really can't figure out. It can range from as much as 50 cents MORE than Premium to 20 cents less than regular in the same week. It seems to be all over the place. That's in town though, the second you get outside of town diesel is the same or slightly cheaper than regular. I would also consider running bio, but I have not done enough research yet to start discussing that.

I also wanted to add that I have flat-towed the mini-truck w/ the 80(mini-truck was on stock tires, but has a welded rear diff) and it was only shady on the twisties in the mountains in the rain. In this case there were no brakes helping me stop it and I never felt like I was out of control. I'm not trying to be defensive, just wanting to add to my experiences. BTW, does anyone know the wheelbase of a Tahoe/Yukon offhand? I've towed w/ a Yukon before and aside from having no power, it towed alright on the highway.

Thanks,

Ary
 

helocat

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I have been looking over putting a diesel in one of my 80’s as well. Going with the stock Toyota 1HD is ideal but due to their price once sitting in the US, not the most economical way to go. I have been considering the Issue option; just need to narrow down the trany’s a bit more. I want the truck to maintain the auto as this will end up being my wife’s DD.

Not sure about its use for towing. I run a 01’ F250 with the Powerstroke so that is the dedicated tow rig. This truck typically is my DD due to all the parts moving around that I do. It is on the third month of running on B100, (100% Biodiesel). This is quite honestly the main motivator to putting a diesel in my wife’s DD, so she can also run the Bio.

I would buget $10k+ to do a diesel swap right. I have done enough swaps (motors/axels/susp.) in general to know better.

If you come across a 80 with an Isuzu please post up a link!

Mark
 

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Don't count on exceeding 20MPG
I see lots of 25MPG claims on the net, but I feel there is some exaggeration.
My experience:
I've had an HJ60 with a 2H that got 19MPG, My brothers HZJ75 with a 1HZ gets 20MPG, and my 6.2 GM diesel FJ60 gets 18 MPG

I guess you can expect a little better MPG with some of the newer Direct Injected turbo engines, but damn are they noisey if comfort factor is a concern.
(I've never listened too or driven a Toyota Turbo diesel)
 
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