FJ60 drivetrain swap questions

[ISB Cruiser]

I am in the planning process of my 83 FJ60 project. The donor vehicle is a 2001 1 ton 4x4 ISB powered Ram. My dilemma is now regarding axle and transfer case selection. I am building this to be as bullet proof as possible for heavily loaded back country exploration while still keeping mileage in mind. So, my dilemma is that I am going to run the Dodge 47RE automatic transmission. I would like to retain the stock transfer case and axles. No adapter is currently made but I can buy a shaft to adapt the trans output to the t-case input. I would have to fab an adapter. My other option is Dana 60's and I am not sure I want to go with full width axles. So I can build an adapter or narrow Dana 60's. Or there is the Atlas option which would require modifying the stock rear axle to center diff or swap to a center diff mini truck rear end. The big question is regarding the strength of the stock transfer case and axles. Can they handle the power of the ISB? Any critique or suggestions are welcome.

 

[ntsqd]

Seems like there are a lot of 4BT swapped 60's & 80's for sale lately. How married to this particular truck are you?

I see the 6BT/ISB as far more engine than a 60 really needs. For all of the effort there are better fitting options.

One way to get around the adapters thing is to use a doubler. Find one that can be bolted to your trans, and can be bolted to the Split-Case.

 

[ISB Cruiser]

I do agree that the ISB is probably a bit of overkill for the 60. AS far as effort from what I understand the engine fits rather well and is about the same as doing a 4BT. There was a customer that brought a FJ62 into the dealership I used to work at that had a 6BT but he went with full width 60's, NV4500 and an Atlas. He was on 37" tires and was claiming roughly 25-27 mpg. Two reasons I want to go with the ISB is for the mileage and the power to haul or tow large loads. My initial plan was to put a VW TDI in my 90 4 runner and do a solid axle swap. After realizing the cost of that conversion and a few trips loaded up with one passenger and the dogs I realized I needed more room. I traded my pristine 4 Runner to a friend for his 83 FJ60. The 60 has at present a Ford 302 with stock 60 running gear. It is a fuel chugging, slow and hot running beast. I then purchased the donor truck that we retired from our fleet for peanuts. The drive train is in great shape, the rest of the truck is falling apart. As far as doublers I have not found anything to connect to the 47RE yet. I spent about 40 minutes going through possible options with Advance adapters. I am considering swapping to a NP205 with a 203 reduction unit. That would get me the proper front drive line exit but still stuck with a centered rear.

 

[ntsqd]

Have a look at High Impact's doubler offerings. One of those may just work.

The 80's rear axle is more centered than the 60's, but wider. I plan to cut my 60 floater rear hsg and flip the center "third" to center the diff. I think that it will work, but I'm too far away from needing it to spend much time on it, yet.

 

[ISB Cruiser]

I just spoke with High Impact and they do have an option for me. It is to run the Klune underdrive / doubler mated to the split case. That is probably the cheaper option also running about 2k and keeping the stock axles and gearing. The only real question I have now is how strong are the FJ axles?

 

[cumminscruiser]

fj60 running gear

Am I a fan of fj60 stuff or what?

I have run stock fj60 running gear behind Cummins 6BT5.9 for ten years straight, all kinds of terrain, not babied, poorly maintained not even rebuilt with 200 K miles, driven over every bolder I could find. Pulled my 23 foot boat to Tahoe 75 mph up the hills, thats as fast as it can go........

I have just rebuilt my 2000 Dodge HD 2500 4x4 transfercase and it's no better than stock fj60, If you want better I suggest FJ62 transfercase.

I have had the axle out of my 3/4 ton dodge rear next to the FJ60 long side axle and besides not being FF they were almost exactly the same size.

Want FF, buy them at SOR.

I did use a NV4500 transmission only becouse of the over-drive and I could not adapt the fj60 4 speed to the cummins. I'd put that 4 speed behind any V8 any day.

Good luck with your project, but I like the fj60 stuff :wings:

 

[ISB Cruiser]

Thanks for the input. I think I am going to run the 60 T-case and axles. Worst case I could call on Longfield.

 

[RHINO]

I am building this to be as bullet proof as possible for heavily loaded back country exploration while still keeping mileage in mind.

the 60 series is about as bullet proof as it will ever be in near stock form. but your also looking for mileage and pulling power so,,, heres my thoughts.

that dodge engine is a powerhouse and anything you dont upgrade behind it will be the weak link.

for ultimate reliability, look at expedition rigs, they are put to a tougher test than most of us will ever dish out and the drive trains remain largely stock

as the mileage part goes, well this a better job of a smaller diesel if you want to keep 60 series case and axles.

i'm down for any diesel swap, but to be "the most bullet proof as possible" you should swap the whole dodge under it and narrow the beefier axles.



edit: cummins not to knock ya but your missing some weak points. just the two you mentioned, i dont care for chain drive transfer cases but the torque loads dont push the case apart like on gear drives, the case isnt any beefier cause it doesnt need to be. on the cruiser axle its the pinion thats the weak link, even the fine spline 60 series which BTW is about the same size as a dana 44. i am all about keeping it toyota and i could sing the praises of toyota toughness on my rig as well, many miles and many trails with 150:1 dbl transfer cases blah blah and only one broken birf, but i know luck has had as much to do with that as toyota toughness.

of course these are just my opinions, based partly on what i like, and partly on 20+ yrs living peacefully amongst land cruisers.

 

[dieselcruiserhead]

I like the 6BT a lot but it is a monster.. Trust me a 4BT is more than enough for a FJ60 if you can find one... Sounds like a nice candidate though... You will get good mileage and of course unreal power (possibly scary power)... Good luck with the swap! The stock axles will hold up just fine I think if you keep it at 33's or smaller for safety. The weight up front is really going to compromise your birfields so toyotasuperaxles.com are a must bare mine. 35's will be pushing things.. I recommend 3.73s in the axles (stock FJ60 gearing) absolutely...

good luck,
andre

 

[ISB Cruiser]

Rhino, thank you. I am still considering running Dana 60's and the 214HD transfer case. The donor truck axles are worthless for this swap though. It has a Dana 80 dual wheel rear and the weak axle disconnect 60 balljoint front. The plus side is that being the 3500 it has the beefier 241HD case. As far as expedition vehicles I would love to have one. I am on a tight budget and so far have a total of under 3500 invested in both vehicles. I figure I can sell off allot of the unused parts to help also. That is a big factor of why I am going this route instead of a 4BT or another smaller diesel.

Andre, I agree completely on 3.70ish ratios. Doing the math with a .68 overdive that will put me on 33's at about 1800 at 70 mph and around 1650 on 35's. Tire size is another dilemma. I know I am pretty much dedicated to a spring over with the Cummins. I would like to run 35's but also don't want to be a monster truck. at this point I am leaning towards narrowed 60's. Custom built springs to drop it back down a little and carry the weight. and probably trimmed fenders and 35's.

I am still open for more ideas and criticism. At this point the FJ60, ISB and 47RE are the only definite in this build. I will post pictures as I get started and throughout the project.

I also would like to say that this site has helped me greatly already. Seeing some of the cargo drawer and water tank setups among other things has pointed me in a direction I was headed for but hadn't figured out how I was going to pull off yet.

 

[cumminscruiser]

fj60 running gear

I would invite you to come over and drive my FJ60, then drive my buddy's FJ60 with Vortec V8, there is a big difference. Mine is like driving a John Deere tractor and his is like driving a Ferrari. He gets 10-12 mpg I get 20-25 mpg. Mine is sprung over his is not. The cool thing is you could drive both and decide what you like better.

 

[RHINO]

most of my criticism on that reply came from the side of building the rig as bullet proof as possible, most of our builds have to make compromises because of budget or other reasons.

i'm in Phx also, and am happy to help out or brainstorm with ya.

 

[dieselcruiserhead]

I'd recommend going and meeting clay (Rhino) and checking out his vehicle if you get a chance, he has an isuzu diesel in his 55...

Sounds like a plan.. I personally wouldn't mess with the 60 axles if you want 33's. That gearing is very fast with the 3.73s. John Braiser (grease cruiser) had a similar setup with a 8 valve 4BT and was able to routinely get 27 mpg which I think you'll be close (at least 22mpg I'd figure) with your 24 valve. The best way to estimate your required lift is get it in there. I've been on 35s twice now, for daily driver it is a large vehicle which is why I recommended 33s as well. You can build a flat or even an inverted spring pack and have a low spring over axle. This is something I've considered for a long time personally (there are a couple threads on ih8mud.com about it) and I'm also doing a coil spring conversion probably some time (or at least I have all the parts to do it from ballistic fabrication) using their adjustable coil spring buckets, a custom hi-steer from 4x4labs and then I can get 4" or so and actually make it work without leafs and even have decent performance up front. You'd just need some really beefy springs like 80 series old man emu heavy bare minimum...

good luck again, sounds like a neat project... Good luck with the sales. It will take a lot longer and cost a lot more than you anticipate unfortunately, just the nature of the beast.... Best, Andre

 

[ISB Cruiser]

Clay, Thanks for the offer. I would love to see your 55. What part of the valley are you in? I'm in central / downtown Phoenix.

Cummins, I would love to come check them out. Unfortunately that's a little far to go for a test drive. Might be a good excuse to make a trip up the PCH though.

Andre, Let me know how the coil spring swap works for you. I am looking at probably low spring over with shackle reversal. I am also probably going to go with a wider flatter spring setup for ride quality, travel and strength. Maybe even a longer spring. For now getting the engine / trans in is going to be the first part then I will play with the suspension and tire setup. If I can pull off a low spring over on 35's that's what I will go with. I know from past projects they always cost more and take longer than expected. I only plan to be ably to recoup maybe 1k or so. between whatever 60 parts I don't use, the 302 and the spare Dodge parts. Short of that I will take the rest in for scrap, for beer money while working on it. Or at least staring at it.

 

[Jonathan Hanson]

Brian, since you mentioned a goal of a "bulletproof" vehicle, I'll add a few thoughts.

In my experience, the further away you get from a stock Land Cruiser drivetrain, the more power you add, and the more components you mix and match, the faster you'll lose your "bulletproof" qualities, no matter how "heavy duty" those components might be individually.

The brilliance (part of it, that is) of the original Land Cruiser design was that it mixed an engine of modest power with very strong running gear. There was no weak link, as in so many other vehicles. Even the front birfields, castigated by so many rock crawlers, are perfectly adequate until you start adding over-33-inch tires, power steering, etc. The birfields on my FJ40 have over 300,000 miles on them and are doing just fine.

When we started researching turbodiesel engines for the FJ60 conservation vehicle project in Overland Journal, we very purposefully aimed at a useful but realistic power increase, which gave us the ability to keep all the rest of the running gear stock. The International 3.0 engine we chose produces about 170 horsepower and 300 lb.ft. of torque - good enough to make the Tecate Divide on the way to San Diego a 5th-gear, 65 mph run now, as opposed to the 45 mph 3rd gear slog with the 2F. Yet the stock running gear (with an H55 Toyota 5-speed transmission added) is more than strong enough to handle the extra power, and we're now averaging between 26 and 27 mpg.

It's very tempting to go for the big power and then have to add bigger axles, etc., but you wind up with a Frankenstein, not a Land Cruiser, and it's highly unlikely you'll enjoy the reliability experienced by owners of stock Land Cruisers.

And be extremely wary of claims of outlandish mpg with extremely powerful engines, whether gas or diesel. Diesels do seem to bend the laws of physics, but they can't cheat them. I've lost count of the guys who swear to me they get 25 mpg in their Dodge Powerwagons towing their 30-foot Airstreams. I just nod and say, "Wow."