Intro, Thanks to the board gurus, and Build/Discovery Thread 1966 Proffitts restored 4BT and SOA FJ40 (1 Viewer)

navydivedoc

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Mostly a lurker on these boards for a few years. Bought a pristine 1991 FJ80, made plans, got an offer I couldn't refuse, sold it. Bought it back, made some plans, sold it again. Bought a ridiculously clean 285k mile 100 series...offer I couldn't refuse, sold it. Finally just bought a 200 series for wagon and DD duties. That thing is great, but not much in the way of exciting stuff to post...blue ridge gear net, Overland tailor sun visor, General tires don't make for the most engaging postings, so I mostly watch and learn.

I have wanted an FJ40 since I was a kid. I grew up in Maine in the 80s, so they were all rusted out and rotten, even the ones from the 80s. My father hated them with a surprisingly strong passion, so I never did get to own one. I had Jeeps instead, 2 YJ wranglers, a nice original 1957 Willys pickup, and we had a string of old wagoneers as winter beaters. If we only knew then how valuable they wold be now, we would have filled a garage with them and waited.

Flash forward a few years, and I managed to get myself quite deep into a Jeep LJ build. LS swap, 6L80, Dynatracs, Atlas, etc. Won't clutter up a Toyota FJ thread with Heap stuff, but this is going somewhere, I promise. Details here if anyone cares Jeep LS

The Jeep went up for sale, as I had "done that" and wanted to come over to the Toyota side. Specifically, I most wanted an FJ45. Found a few, nothing quite hit. Got in touch with a wheeling buddy of mine and asked if he knew of anyone looking to trade something for a Jeep LJ. Low and behold, he sends me a pic

FJ40 Cummins.jpg


I haven't even told him I'm looking for a Toyota, let alone an FJ. He's a rover guy, so I figured I might get a shot at a nice series truck or defender. So, I send back "definitely interested".

Deal is struck, and we are definitely on.

It's a Proffitts Stage 3 frame off restoration from a few years ago, back when they were still doing a lot of 4BT conversions. To make room for the Cummins, it is a SOA build. All the usual goodies, plus ARBs front and rear. H55 5 speed and split case. I'm not a huge fan of the roof rack or the current wheel/tire set up, but overall it looks like an interesting new project. Owner gets a jeep that he wants to match a CJ-2a and classic Power wagon project, and I finally get an FJ40. Not a 45, but close enough for a start.

Negotiated into the deal is a Cummins R2.8 repower motor still in the crate. And a broken frame and rotted body BJ40 with decent axles, running motor and good trans/t-case

I've been digging around here for a couple of years, but now have dug in fairly deeply on what I can find about these SOA and 4BT swaps. Seems to be a mixed bag of opinions as always, but they tend toward "it's a farm implement, too loud, too many vibrations you'll hate it" for the Cummins. For the SOA, also a mixed bag. Done properly, which I assume this is, seem to be pretty easy to live with. Just TALL. I do wheel, so the capability is desirable. Will I wheel this particular rig enough to justify a SOA set up vs an OME 2.5 and 33s? doubtful.

3 ways this can go, and I am undecided which is really the best. Opinions welcome.

1. Drive it as it is, accept the compromises of the Cummins and SOA, have a very capable wheeling rig. "Don't fix what isn't broken". This is easy, and is at least how things will start. Unfortunately, it doesn't fit into my garage at home so it may be offsite and some distance from me for now. Not ideal.

2. Plan to put the R2.8 repower into the truck, and do a SUA reversion. Sell the 4BT. I've already spoken with Proffitts about this, and they are the easy answer. I put feelers out to Valley Hybrids and Torfab, but have not heard back from them. My brother and I could do it, not strangers to engine swaps, labor and time vs money. As the H55 and adapter is already there, the re-engineering is somewhat less than usual on a repower. More money and time, but it will be a perfect FJ40 at that point.

3. What I really want is an FJ45LPB. It doesn't really need to be a true frame off like this Stage 3 Proffitts, I'd rather have a clean driver. Do I sell the FJ40 as it sits and find a 45? Maybe easier said than done. If I'm going through the repower and SUA expense and work involved, do it on the truck I want the most. That said, I do really like a FJ40, and the heavy lifting is done on the one I have. This is the most expensive option in all likely reality.

So, those are the options. There isn't really a true perfect answer, I'm just putting out there as my thoughts right up front. We'll see. If there is a unicorn out there who happens to want a 4BT/SOA restored FJ40 and by some miracle has an FJ45 and wants to talk trade, by all means hit me up. Otherwise, time will tell.

From a technical standpoint, I have found many great threads on the R2.8 conversion. A ton of very helpful pics, tips, parts, etc. I won't reinvent the wheel here as I don't have any unanswered specific questions yet.

Less clear is the SOA to SUA conversion. I can't find much about that direction. I assume this had a proper cut and turn. As I am getting the BJ40 with the project, it will have axle housings/full axles I could rehab and use. Some questions I do have:

1. Is there any reason the BJ axles wouldn't work? Will the 3rds, axle shafts, etc work with that housing or do I need to rebuild what is there? How much of PITA would it be to cut and turn the axles back to stock? Any reason this couldn't be done?

2. Are the spring perches modified for an SOA? I haven't found a thread indicating yes, but I can't seem to confirm no. Bottom line, will new springs drop in?

3. Assuming I drop an OME 2.5 kit in, with appropriate axles either re-cut and turn or new, what else will I need to change? Steering components? Knuckles?

Any help appreciated, and I will post more pics and info as I get this ball rolling. Thanks to all for so much useful information and the time that took to get it out there for the rest of us.
 

YoYoHo

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Sweet looking truck, on teh current market I would serioulsy consider trying to sell it as is and building what you want. There are a few 45's kicking around as start points.

The Bj40 diffs should work, being a 66 I doubt it has the factory diffs in it still .

You can cut and turn them back but I wouldn't bother as you will also need to do shock mounts, leaf mounts etc. Just use the BJ's if you want SUA.

Spring Perches are moved from bottom to top but often they leave the stock ones in place as well.

Get a picture of what steering you have now and I can tell you if it will work

As you pointed out Proffits are doing a lot of different things now to then as are most shops. I would not pull the 4BT to put in the R2.8 if you really want a 45, there are still a lot of people who love the 4BT and a 4BT SOA Built 40 that has a resto at that level will be a salable item. Heck if I had a 45 I would swap you as I am to tall and fat to fit in a 45 lol
 

navydivedoc

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Thanks Yo. I'll get pics up once I get this thing in my hands. I realize I should have asked are spring hangers moved, not perches. I'd hate to cut anything off a powder coated frame if I didn't have to.

For now, it will be a fun toy to play with and I can keep researching. Good times. Fairly deep down the patina resto rabbit hole at the moment. Maybe wngrog will decide in a moment of weakness that he is over his 45, or the 40, and wants a full resto with the 4BT/SOA. Or there is some other unmolested prize out there just waiting in the wings. Fevered dreams.
 

YoYoHo

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The picture you did post shows it has a SR ( Shackle Reversal ) which is always a can of worms opinion wise and I would expect it it was setup as a SOA with SR you will need to do some changes as the non SOA Springs will need more Arch and thus lengths and geometry can change.
 

FJBen

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If you have always wanted a 45, I would say sell this. You will Probabaly always in the back of your head want one. Market is high on 40s and a restored 40 with a 4BT will sell quite well on bring a trailer.

45s are cramped though. I’m 6’4-6’5” and skinny and it was a really tight fit in my HJ45. I would definitely recommend driving one first if you haven’t. @wngrog 45 is sweet, although I’m pretty sure he hasn’t broke the 6’ barrier or hit his growth spurt yet. :p

Find a 45 and go from there if you aren’t fully enamored by this one.
 

navydivedoc

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If you have always wanted a 45, I would say sell this. You will Probabaly always in the back of your head want one. Market is high on 40s and a restored 40 with a 4BT will sell quite well on bring a trailer.

45s are cramped though. I’m 6’4-6’5” and skinny and it was a really tight fit in my HJ45. I would definitely recommend driving one first if you haven’t. @wngrog 45 is sweet, although I’m pretty sure he hasn’t broke the 6’ barrier or hit his growth spurt yet. :p

Find a 45 and go from there if you aren’t fully enamored by this one.
I appreciate the advice. Best to go slow and just see. I may like the 4BT better than I expect, and this one will wheel almost as well as my old LJ.
Fortunately, I haven't had my growth spurt yet either. Rare that thin and 5'10" has advantages, but I'll take 'em where I can.
 

navydivedoc

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Im a giant in FJ45 terms at 5’8” and it is the last truck I would ever make my full time Cruiser.

Love it but it’s kind of like owning a motorcycle. Fun but not practical except the way I use mine on the farm.
This is definitely good information. I guess I need to find myself one to try on. Just enough excuse to have the 45 for driving the couple of miles into town and running a few errands. Keep the 40 for trail and longer run duties. 200 as the DD. That's not a hard pill to swallow.

No stranger to slow and uncomfortable in the rigs. Had this original 1953 Dodge M37 as the last "short trip to town truck"
M37 Fall.jpg


Let me know when you're ready to part with that 45, my favorite truck on Mud.
 
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navydivedoc

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I just really read what you posted.

My take.

Sell the 40. It’s cool but not an expo type rig unless you are in Alaska smashing through bogs or hitting lots of Rubicon type stuff.

--Excellent point. If I was still living here in Virginia long term, I'd need the expedition rig. But, moving to New Hampshire next summer, and all of the Vermont wheeling is next door, so within my tolerance range of the 4BT. But, I'm pretty well over the harder side of wheeling. My suspicion is the SOA will be more than I want long term.

Talk @cruiserjunktion out of his red LPB.

--Oh, I've been eyeing that one. What's the likelihood of getting the roller/brush paint job off and down to the original paint with enough left to run with? I've considered getting in touch with him, but hate to waste people's time, so it seemed wrong to do before I even had the 40 home. I may exceed my quite-tolerant spouse's threshold if 2 come home at once.

Buy a 60. Build it right. 60s rule.

--Yes, several in my circle. Hard to find in the east. I'll have to travel to find one without cancer.
 

navydivedoc

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Nice to hear a vote from the other side.

Roof rack definitely goes. New set of wheels and tires probably. FJ cruiser steel with a set of the new Kenda 35x10.5r17 I think would look nice, except for the need to run spacers.
 
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If thinking about keeping the 40, I’m a big fan of SOA with a SR and relatively flat stock springs. Makes for a great ride on the road, and highly capable off road vehicle as well. just my opinion having taken a SUA and SOA thru the Rubicon. I know my “new” FJ40 will be just that - SOA and SR.

Good luck! Can’t go wrong. I think 45’s are really cool. Love to have a SWB to add to my fleet of vehicles.
 
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If u had deaver or alcan make you a set of leaf springs in stock height but with reverse eyes it would lower your suspension height by about 1.5"-2" from how it sits now. But could retain the soa setup.

Another option is keep the 2.8, sell the 40, buy a ratted out 40 for a few grand, buy a extra cab fj45 3/4 tub from aqualu or complete tub, a long bed from aqualu, and a frame from aqualu for a extra cab longbed. Use the ratted out 40 for all the missing little parts you'll need and install the 2.8. Extra cab will give more comfort and practicality. Could have a factory style soft top made for it
 

navydivedoc

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If u had deaver or alcan make you a set of leaf springs in stock height but with reverse eyes it would lower your suspension height by about 1.5"-2" from how it sits now. But could retain the soa setup.
I think the issue is the 4BT needs the full SOA that it has now. Talking to Jeremiah Proffitt, there doesn't seem to be any room to lower it on this build.

Another option is keep the 2.8, sell the 40, buy a ratted out 40 for a few grand, buy a extra cab fj45 3/4 tub from aqualu or complete tub, a long bed from aqualu, and a frame from aqualu for a extra cab longbed. Use the ratted out 40 for all the missing little parts you'll need and install the 2.8. Extra cab will give more comfort and practicality. Could have a factory style soft top made for it

Oh man, that is another rabbit hole that I will start down. I have the ratted out BJ40 coming in as part of this deal already. Thanks for the tip, aqualu tub on this build too, but I really hadn't researched it. Thanks!
 

FJCowboy

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It was time, the Jeep had its run. Get your 200 back yet?

Glad to see you left the darkside of J**ps, but I will have to say it looked like a really nice build. I've got a couple of buddies that run LJs and they are probably my favorite of that family. Good luck with the current/future build and I'm sure it will be fun either way.
 

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