SOA Musings... (1 Viewer)

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Tigerstripe40

SILVER Star
Joined
May 3, 2004
Threads
159
Messages
2,452
Location
Utah
I know its been done to death.
I've searched.

I am considering doing a SOA on my FJ40 and I am looking at a number of different options.

First, here is how my truck is currently setup.
1976 FJ40.

Drivetrain:
2F that was rebuilt about 11 years ago, probably has about 80k on it. Runs strong.
NOS SM420 from a Gamma Goat with maybe 20k on it.
Mike Smythe plate adapter.
Stock '4 speed' t-case though it has a conversion gear to be able to adapt it to the SM420. So far as I know the t-case has never been rebuilt.

Front axle:
FJ40 front end with FJ60 knuckes and v6 4Runner calipers. All new OEM hardware.
Completely rebuilts about 2 years ago.
30 spline longfields.
4.88's w/ ARB air locker. New diff/pinion bearings at this time
A bunch of spares (4 birf's, 2 sets of stock inners)

Rear axle:
Stock FJ40 rear housing w/ stock S/F axles.
4.88 R+P w/ stock carrier and a lock right.
Monte Carlo rear disc brake conversion.
1 set of stock rear axle shafts w/ c-clips.
The rear axle was also rebuilt with new rear axle bearing and seals about 2 years ago.

Suspension:
OME Dakar springs. The front springs are about 4 years old, the rears about 3 years old. Front shackles are OME anti-inversion greasable rear shackles. the rear shackles are 2.5" over stock Man-A-Fre anti inversion shackles that have been modified (the anti-inversion cross bar was removed to allow the shackles to flex properly. Total lift is about 4-5" total to fit 35" tires.

Steering:
Saginaw Power Steering conversion.
Drag link uses a 1-ton Chevy TRE on the pitman arm end (pitman arm is a SUPER beefy unit out of a Ford E-450) and a stock 76 FJ40 TRE on the other. OD of the drag link is 1-3/8". Tie rod is a BudBuilt 1.5" 3/8" wall tie rod with stock FJ40 TRE's. I've been able to pick the front end of the truck up with a fork-lift and the Tie Rod won't deflect.......

Master cylinder was swapped out for a new FJ80 large bore MC w/ Summit racing prop valve.

As it stands now, I consider the truck for the most part bullet-proof. I've run some pretty tough trails, but have not been very aggressive with the truck as I need to drive it home. I would like to do a spring over for ride quality, articulation, and added capability, but I have a number of different options.

I have a set of FJ60 axles, both front and rear with most of the parts complete or good cores. I know the axles are 3" wider than stock on the long side, so at least in the front, outboarding of the springs would be necessary.

On the rear, I would like to have the better parking brake that the FJ60 rear axle provies, as the t-case mounted parking brake has been marginal if not lacking for the last few years. I've put new brake shoes in it. I have a kit from spector to rebuilt the parking brake using all new parts, however, I wonder if the 35s with 4.88's might be too much for the t-case drum brake to be able to hold even with new parts. My feeling is that converting to the FJ60 rear end with drum brakes and the parking brake might be more beneficial than the RDB's I currently have.

Springs:
I've seen many threads about the stock FJ40 springs being the best for a spring over. However, these springs are aged, and there don't seem to be many available now. While at this time, I don't think that OEM spring availability is going to be a problem, my concern is that 10 years down the road, OEM springs won't be available at all... CCOT doesn't seem to offer a no-lift spring for FJ-40's any longer.....

My conclusion is to build the SOA with OME Dakar springs, using the front FJ40 housing with spacers, and the rear FJ60 housing for the e-brake setup.

While I am at it, I am thinking about the t-case....
Since I have the SM420, I don't need a 4:1 Orion, however, the cast iron case is appealing. I've long considered the ToyBox with a split case. I think this would give the truck the best combination of gearing.

Which is stronger, the Cast Iron Orion, or the split case. Drive shaft mod's aren't a concern since I have to mod the driveshafts in any case doing a spring over.

Sorry to babble a bit. These are things I've been considering.
 
Tiger sounds like a very capable rig. First I dont think they an adpter that fits split case to ten spline of the 420 so if your planning toybox than split case that adds to the cost so orion may be a better option I believe you can get it 3.2 or something if you didnt want a 4.1 case but you lose all the different choices that a toybox provides. On a the parking brake I think you would have to install parking brake pedal from the 60 to get the pull required on the drums of the rear axle know its a problem with caddy calipers.Have you thought of a micro loc to help suplement your t case brake? Also just use the 60 front housing if you end up going with the rear and avoid spacers I read a build awhile back where they didnt out board the springs and notched the housing alittle with no ussies but dont remember where I saw it hard core maybe pirate Ill look and see if I saved link. Use some 60 springs for the rear and ive seen people use them {60 rears} up front. Ive got a set im going to try on the front of mine but Im still a few weeks from setting the front up. Lift spring will be way to much lift. Pm me if you want i would love to check it out in person when Im up north or when you bring it south
 
For what it's worth, I LOVE my SOA. We did the shackle reverse as well while we were add it. I did my best to keep it as low as I could. We drilled a hole and sleaved the frame instead of welding the spring perch to the bottom of the frame, and did a few other things to keep it as little lift as we could (I figured it was easier to add then to remove height). I ended up VERY happy. The ride is awesome. I'm using Rancho 9000s and it's a great combination. I can keep them nice and stiff on the road (without the hardtop it cornors better then some SUVs) and nice and soft on the trail and it's a much nicer then stock ride off road. The flex is awesome. I didn't use 60 axles, but I don't see why that would make that much of a differance in ride quality. It was a lot of work, but it was well worth it.
 
If I was to do my 40 again, I would use fj62 rear springs, in the rear, and a reworked stock 40spring (with add a leaf) in the front. I put a full float 60 series rear axle in mine and use the stock e brake that it has.
If you can find a stock pull handle from a 60 or 62 either will work (as far as I know all 60/62 series had the same kind of e brake that was applied by pulling a lever between the seats) I also bought a toy box and use that as the adapter from my sm465 to my split case. both the orian and the split cases are great, however the orian uses the front nose cone of a stsndard case... for that reason I like the split case. again both are very good but with the toybox and the split case I have a lot of options... Im really dont like the spacers , to me they just put leverage on parts..... just a thought.
 
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I like your conclusion, but agree with cruiserjunkie and say use the 60 front axle. However, I would go ahead and outboard the springs (done right, it looks nice!) and use the 60 front axle. IMO spacers are bad juju.
 
I did the 60 series springs and axles. It was a lot of work, but totally worth it!!! The added stance really makes the rig more stable in comparison to other 40's I've been in.
I also did a SR, but.... That was a ton more work and I'm not sure it was worth the effort. If I knew what I know now... I'd have left it stock!!
 
I did the 60 series springs and axles. It was a lot of work, but totally worth it!!! The added stance really makes the rig more stable in comparison to other 40's I've been in.
I also did a SR, but.... That was a ton more work and I'm not sure it was worth the effort. If I knew what I know now... I'd have left it stock!!

My FJ40 is beat. While the drivetrain is in tip-top condition, the tub is pretty much trash. For my truck to look nice, I need everything from the firewall back, as well as a WS frame and fenders. So I am building this truck to be a beat-it-on-the-trail truck.

I am in the market, though, for a 4/80 production date 40 series that is in good shape body wise that I would leave either all stock or mostly stock with OE upgrades such as an H55 transmission.
 
Stock 40 springs are readily available, every last person doing a SUA lift has some to throw away. Offer to trade your springs for some OEM ones and people will line up so swap with you.
 
Tigerstripe40 said:
My FJ40 is beat. While the drivetrain is in tip-top condition, the tub is pretty much trash. For my truck to look nice, I need everything from the firewall back, as well as a WS frame and fenders. So I am building this truck to be a beat-it-on-the-trail truck.

I am in the market, though, for a 4/80 production date 40 series that is in good shape body wise that I would leave either all stock or mostly stock with OE upgrades such as an H55 transmission.

Sounds GREAT for a trail rig my friend!!
Mine too was pretty hammered but I went ahead and fixed it all up. Just my OCD!!
if you need any info from me, just shoot me a PM!!
I have a build thread in the "hardcore" section ad well. It LOOOOOOONNNG, but flip through it and pull out what helps you.
I have done two SOAs, and that is one of the single best mods you can do for off road performance on these rigs. Ride is better, flex is ridiculous and it just looks fawkin great.
The other upside for you, is that most of the really expensive components are in place (locker, gears, longs etc.)
Get the ruff stuff kit and go!!
I've seen the housing notch (mentioned above) Not my favorite mod. I'd outboard the springs, IMO!
 
We did the shackle reverse as well while we were add it. I did my best to keep it as low as I could. We drilled a hole and sleaved the frame instead of welding the spring perch to the bottom of the frame, and did a few other things to keep it as little lift as we could

I agree with most of this except that going through the frame can keep it lower than putting the perch on the bottom. With fairly flat springs and a steep shackle angle you can put the perch on the bottom and have it exactly as low as through the frame. The limit on how low it is is how close you can get the spring eye to the frame when it is totally flat. With the perch on the outside, this happens when the shackle is flat, 0 degrees. With the perch through the frame, this happens at something like 30 degrees, depending on shackle length. I believe the flatter shackle, and therefore the perch outside the frame, will result in a better ride.

If I was to do my 40 again, I would use fj62 rear springs, in the rear, and a reworked stock 40spring (with add a leaf) in the front. I put a full float 60 series rear axle in mine and use the stock e brake that it has.

I have fj62 rears in the rear and fj55 rears up front. The front springs have one leaf removed so they are nearly flat. It hasn't been flexed much yet, so I may have to put it back sometime.

I have a cut-down fzj80 full-floater with e-brakes, but I kept the t-case e-brake. It's geared 4:1 by the rear end gears, so has 2x the braking power of a pair of them at the wheels. If yours doesn't work it needs to be adjusted or repaired.

I've seen the housing notch (mentioned above) Not my favorite mod. I'd outboard the springs, IMO!

I had to notch my front fj60 housing some even with the outboard.

I've got it in my head that with a notch on both sides I could get my front end lower by at least an inch. I probably won't do it over since it's new, but if I was designing another one I'd want it lower than what I have now and I think it could be done. I'd be shooting for 1.5" lower than what I have. I'd have to do something to the rear to get it down there to match.

The fj62 springs I have have all the leaves in them. It has great cargo capability, but I may need to remove a leaf to get some more flex out of them, especially when I take the top off.

E-lockers front and rear too. :steer:
 
Just curious, everybody seems to be using 60 springs, I am putting 70 springs on mine and reversing them. I believe I will get more articulation and a better ride. I am going SUA to begin with to see what I have and then if necessary will go SOA. Not trying to hijack but why is this not a more popular conversion?
 
Where I live, in the USA, 70 series cruisers were never imported in mass like the 40's and 60/62's were. so there aren't many of those stock springs available.

60\62 springs can be found easily and inexpensively. I am sure someone else can fill I'm the details, but I think the rear 60 series springs are a little lounger than the 40 springs, giving better shackle angles.
 
What UP James!

My offer still stands to trade you straight up ha ha ha! I'm jealous of what your rig has done and will one day be able to do!
 
Where I live, in the USA, 70 series cruisers were never imported in mass like the 40's and 60/62's were. so there aren't many of those stock springs available.

60\62 springs can be found easily and inexpensively. I am sure someone else can fill I'm the details, but I think the rear 60 series springs are a little lounger than the 40 springs, giving better shackle angles.

I don't even know how long the 70 springs are compared to 60 springs. The above is 100% true. Availability.

If I remember correctly fj40 springs are about 44-45", fj60 springs are about 48" (with weight on them). It might be possible to use them on the rear with just a custom-length shackle and get a good shackle angle. I used a long shackle from Mark's Off Road and moved the rear hanger to get it where I wanted with a steep shackle angle. It rides like a Cadillac. I'm anxious to get the top off and the roll cage in place to see how it rides topless.

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What is custom about the shackle? Does our have a different pin diameter at the top and at the bottom?
 
Resurecting this thread.

I've gathered parts and am moving towards turning wrenches onthe truck.
I made the decision to follow through with this, finally, and have most of the parts necessary now.
I am not spinning wrenches on the truck until I have EVERYTHING except Driveshats, shocks, and drag link delivered and ready to go.

What I have so far:

Stock 81 FJ40 springs
83 FJ60 front housing -stripped, clean-ish and almost ready for cut and turn.
RuffStuff Spring Over kit for FJ60 axles under FJ40.
All Pro Offroad high steer arms
Marlin Crawler FJ60 length Tie Rod w/ 80 series ends.
Will retube front drive shaft (not planning shackle reversal).
double cardan joint from an FJ60 to splice onto my rear driveshaft.
30 spline longfield super set for FJ60 (just swapping the inner shaft on the long side)
Knuckle Rebuild kit w/ trunion bearings.

Still to get:

Spring Bushings
Spring mounting hardware for shackes and spring hanger
Spring Centering pins
Trac bar kit
Cut and Turn front housing (prefer to have Cruiser Outfitters do this).

Shocks*
DragLink*


What I am wondering about right now, is how to attatch the springs.
I got the RuffStuff spring and shackle hangers.
I noticed that they have 1/2" holes, which would make me assume I should use a 1/2" bolt.

However, the late model FJ40 springs I have use 18mm spring pins (between 9/16 and 5/8). The early model FJ40 springs I have use 15mm pins (.709" between 11/16" and 3/4").

What I am wondering here is, do I need to find a spring bushing with a 1/2" diameter for the spring eye I am going to use, or should I drill out the RuffStuff spring hangers to use the larger hardware?

My other option is to cut off the stock spring and shackle hanger hardware in the front, use the OME spring bushings for the earlier stuff and then reuse the shackles and hangers I already have -this isn't as beef as the RuffStuff and I will feel like I have wasted some $$$.

Also, I am going to use this thread as my build thread so I am not starting YET ANOTHER SOA thread. :D
 
I went to best steel spring and found the bushings I used( used 60 springs front and rear) Have you thought of using rear60 springs it would work great on your rig
 
Is best steel spring a company in Utah?

I have thought about using the 60 series stuff.

I've alredy got the stock FJ40 springs and the OME springs. I am actually considering using the stock 40 springs up front and then removing a leaf or 2 from the OME's in the rear and redo the shackle. That way I have a set of spare spring in case I break anything.
 
Considerations:

1. My rig has at least four different spring bushings overall. I wish there were, at most, two.
2. Ideally, you would have all the weight on the front end with the high-steer installed before tacking in the perches and the C&T. That way you can check the tie-rod/spring clearance, pinion angle and caster angles. If someone else does the C&T it's a crap shoot.
3. I'd use the stock springs front and rear. It's going to be hard to get the lift springs to match the front springs without making both front and rear higher than it needs to be.
4. Focus on making it as low as you can. I modded my perches and my outboard kit and now that it's all done I can see where it could be almost 1/2" lower and I wish it was.

In my opinion, you (and I) chose the best high-steer arms and tie rod solution.

What power steering with no shackle reversal?
 

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