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Coil/Radius arm SAS 1st gen Trooper - fine tuning/new mods

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I'd been scouring craigslist, ebay, and the planet since about October of last year for the right rig. Came close on a few, and go figure, all of them were out west. I just couldn't pull the trigger on shipping something across the country unless it was really justified. Then Jim's (RubyTrooper) 1991 trooper came on the market. I'd seen pics of it and read up on it previously and thought "that's the way I'd do an SAS if I had the time". So when it came on the market, although it was more than I'd ever paid for an Isuzu, the price barely covered the SAS and upgrade PARTS, not to mention time, nickel and dime stuff, and the rig itself. So coughing up another wad of dough to transport it from WA to NC would be just fine. I'm very busy with work these days, and I don't have the space for a full on build right now, either. I really just wanted to go wheeling again, and I needed something with room for the wife and kiddo. So not having to spend a year building something was worth the price on it's own.

I'm going to use this thread for documenting the changes, repairs, upgrades, and that sort of thing. I have a few things that need to get done ASAP, and a few ideas to really iron out the details on this already awesome trooper.

Enough chit chat, here's the pics:

Just outside Charlotte, where I finally got to see it in person (bought it without driving it, touching it, or even seeing it in person!)

Drove it about 200 miles home on Sunday. Hit 75mph and things felt OK! My driveway in Raleigh:

I actually have been driving it around a lot the past few days, but this morning it up and quit on me. I had starter and fuel, so I grabbed a new MSD blaster coil, replaced the old one, and was back in business before lunch. Glad it happened 2 houses down from mine, rather the 100 miles away.

The good stuff right there (D44 w/ 5.38's, OX locker)

Notched frame for steering clearance:

Rear D44 w/ detroit & boat anchor truss that I may remove most/part/all of:

Body lift, exhaust routing (both of which will probably change)

In the backyard getting prepped for rear spring swap:

The stock leaf packs are dead beat. With the detroit in the rear, It compresses the pass side suspension on acceleration. I'm going to try using the OME HD dakar leaf packs for 1st gen IFS 4runners. These are roughly the same dimensions as the stockers, but will be closer to the stock 'zu arch. I don't want any more lift than stock packs, and these are about +2" on toyotas which should put me in that range.

Other stuff I'll be doing over the next few weeks/months:

- Bumpstops all around
- Limit straps up front to keep the driveshaft from binding
- Potentially an anti-wrap bar in the back if the new springs don't control it well enough
- Work on a permanent fix for the fricking 2.8 exhaust leaks
- Round headlight grill swap
- Get the E brakes hooked up and working

Further down the road:

- Reduce body lift. IMO, it's wholly unnecessary to have a 3" BL with the SAS. It was on there pre-SAS. Reducing it will require extensive reworking of other stuff, e.g., sliders, exhaust routing, shifters, gas tank lift, etc. I really don't like excessive lift when it's not needed. I like to keep 'em as low as possible to fit the tires through the suspension cycle. The SAS is probably as low as it can be without sacrificing uptravel (and there's only 3-4" currenly). I'll probably reduce the BL to 1-1.5" in order to keep the gas tank tucked up a little bit, and also keep things a little easier to get to when doing maintenance/repairs.
- Bigger tires! The current 35's have nearly 100% tread, so I can't justify going bigger just yet. When I do, I'll probably switch to 10" wide wheels for a little extra track width, and also throw in some inner-tube style inner beadlocks.
- Complete the OBA system. there's a tank and plumbing already there, just need a compressor.
- 3.4!!!!!!!!!!! The 5.38's make a big difference, but it doesn't change the fact that I'm probably putting less than 100hp to the ground in a 7' tall, 4000+lb brick. Mild build plans, just the typical mid range cam, bigger TBI & bored intake, get the heads flowing as best I can, and really just try to keep it reliable. I'd rather it start and run trouble free every time and have 160 hp than be broken down half the time with 200.
- Chromo bits for the axles
- Winch
- Rear bumper
- Armrests - lol, the one thing I hated about these things (the non-LS or RS models). I'll be trying to find LS/RS front and rear seats in the classifieds/boneyards

Anyway, hope to see a lot of yall out on the trails over the next few years! It's been too long :mrgreen:


Pg 1: Intro, lofty goals, rear 4runner Dakar OME leaves, front RE 3.5" lift coils, 1.5" wheel spacers all around
Pg 2: ECGS work - front driveshaft, limit straps, etc
Pg 3: "Round-eyes" grill/headlight swap
Pg 5: Distributor saga
Pg 6: Corbeau Baja RS reclining suspension front seats installed
Pg 8: GM jounce style front bumpstops installed
Pg 9: URE wheelin', sliding center console armrest
Pg 10: 37" Pitbull Rocker radials and interco birddog wheels
Pg 11: RCV's installed (by MetalWerx)
Pg 12: Big Creek wheelin'
Pg 14: Warn winch w/ synthetic line, URE wheelin'
Pg 15: MetalWerx built swing out tire carrier rear bumper, General Grabber X3 tire release event @ URE, Trooper in General promo video, broken shock mount fun, Bilstein 51xx series shocks
Pg 16: 3.4 swap saga begins
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You ever get just about done with a project and realize: "dang, I totally should have done this whole thing differently"?

I finished up the rad and fan mounts, and made some baby steps on the wiring, but I'm not really digging the end result of how I have the rad and fan offset, all to dodge the steering box that is moved way fwd on the frame rail as part of the SAS. I'm thinking that I may step back and look at what it would take to mount a steering box with a forward pitman that mounts inside the frame rail. I think the Astro van box will be the ticket. Outside of the frame forward pitman won't work with the coil mounts in the way. My panhard is mounted right below where the box would probably end up, so I need to do more investigation. I could go with an outside the frame rear facing pitman box if it's far enough up the frame, facilitated by an extended steering shaft with an extra ujoint in it.

I also want to delete the oil cooler lines & the smog pump, and really just get rid of a bunch of junk in the engine bay. I have the correct tensioner to get rid of the smog pump, but I'll need to also pull the pass side exhaust mani to replace a broken bolt/stud while I'm there. I think between that a building new motor mounts, I'll end up with more room in the bay and less things to potentially go wrong.

So it looks like I'll be tinkering on this thing until next Fall haha :blackeye: :blackeye:
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Fall is right around the corner bubba!
hessmess said:
Fall is right around the corner bubba!
Only 2.5 months til Uwharrie - I've got my work cut out for me!
Well, it looks like there would be a lot of work involved to switch steering boxes. Changing to an outside of the frame rear facing pitman wouldn't work because my body mount is in the way. And then the panhard/track bar mount is smack where an inside the frame fwd facing pitman box would sit. I may could run a new track bar bracket off the outside of the frame to make it work, but I would need to mock some stuff up. Lots of noggin scratchin' to do.
Would moving the trac bar mount outside not cause rubbing issue when turning?
btw1549 said:
Would moving the trac bar mount outside not cause rubbing issue when turning?
It's just ahead of the coil mount hoop thingy. So its pretty out of the way of tire scrub. But it would be tricky to mount the steering box on the inside of the frame and have the track bar mount on the other side, with the track bar running underneath.


I find myself very close to just going to leaves. When I look at the pros and cons to make this suspension work better or just unhackify other interferences caused by the suspension, leafs become very attractive.

This suspension doesn't net me more travel than I'd have with a leaf setup (driveshaft bind prevents using available droop, axle side track bar mount/frame and upper link mount/motor mount interference prevents more compression). It may plant the tires a little better on the trail, but I don't know for sure. It's not great on the road, and lowering it a few inches without a lot of other work eats up most of my compression travel. So redoing track bar mounts, fabricating higher clearance motor mounts, building new track bar as well maybe also a new tie rod and drag link, or cutting all that out and welding in some spring perches and hangers....


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What about moving it to the other side?
If you mean moving it to the rear of the axle, I believe there will be oil pan interference. I will check tho - if there's a way to snake a bar back there with a few bends to clear everything, I would be fine with that. Would open up a lot of real estate.
chuffer said:
Full hydro it now?
I'm not comfortable with absolutely no steering if the motor isn't running. I like the mechanical linkage.

I looked and there's no good way to run the track bar behind the axle. Upper links and oil pan in the way. If the upper mounts weren't where they are I could probably make it work.

I think a part of the overall issue is the "Y link" radius arm design, with the lower mounts flush with the bottom of the axle tube, and the uppers above the pumpkin. High clearance underneath, crowded up on top. If my radius arms were the traditional Ford truck/Bronco or FZJ80 Landcruiser design, where the radius arms mount much lower on the axle, I wouldn't have as many interferences, and there would also be more room to mount the track bar on either side of the axle.

I do think I'm going to be able to live with the relocated fan after all. It's not the cleanest solution, but I need to get a new radiator, as mine got more dinged up than I thought when it fell off the table when I was fitting up the fan :( Swapping to a different box is just going to be too much to bite off right now.

So where does all of this leave things? If I want to reduce ride height and improve suspension travel, I'm still left with building and relocating the track bar mounts and building a new track bar, and redoing the motor mounts, if I leave everything else alone. Otherwise, I can redesign the radius arms and mounts themselves, plus the track bar. Or, slap a set of leaf springs under it and cut all the extra stuff out of the way and go on with my life until I'm limited by that setup, and THEN go with something more complicated.

OH, in other news, I'm not diggin the bigger alternator, it actually rests against my battery. So, I'm just going to go back to the stocker, but a 100amp version instead of the 85amp. I'll upsize my charging wire and grounds as well. If that's not enough for the fan, I'll upgrade again.
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Nothing going on lately, mostly working on the samurai. New radiator should be here today, and I'll remove the fan, old rad, tensioner pulley, smog pump, exhaust manifold on pass side. Then I'll be trying to fix the broken exhaust manifold stud, and put everything back together minus the smog pump, routing everything 3.1 style. Then I'll install rad and fan, wire that joker, install alternator, belt, and get her making vroomy noises again.
New rad showed up. Need to modify for mounting the fan, get it back in and get it wired.

Got the rad, fan, alt, alt braces/mounts, smog pump, tensioner, and exhaust manifold off.

Need to get the broken stud out of the head, that will be fun. I have exhaust manifold gaskets and a new stud on the way.

If I can get Humpty Dumpty back together again, and running, I'll just have some body stuff to weld back up, and reinstall carpet and seats. Oh and I have to finish up the gas tank skid mounts.

Buddies want to do a uwharrie trip in a month so it's gonna be a mad dash.
FINALLY got the broken stud out of the head. Only took a dozen or so tries.

Location, angle, visibility were tough. Only had a few threads sticking out. Would have been very difficult to get a drill lined up to extract any other way.

Now I'm waiting for a break in the rain to start putting stuff back together!


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Got the stud I needed, installed exhaust mani, alt, brace, rodeo tensioner, deleted the AC bracket and the idler there, as the belt wouldn't fit without it. Installed PS cooler on rad, fan on rad, whole shebang in the rig. I need to turn over the motor and try expel the rest of the old coolant and PS fluid and get everything topped back off and burped/bled. Still need to wire the fan, too.

Also need to figure out the steering column solution, likely going to have to pull the column, because I can't see anywhere between the firewall and ujoint at the box where I can disconnect it. Fun.

Got the cargo area hole welded up, but my old welder must have popped an internal breaker or something because it won't turn on now. Time to put together the new dual voltage rig and gas cylinder and try that out on the remaining body work. Got a patch to do on the drivers side beside the bench seat area, angle iron to clean up the rocker cuts.

I got one side of the fuel tank skid done, just need to do the other and that will be wrapped up.

15 days, oh boy. :blackeye:
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Welded in patches in the floor (YUGE PITA, from blowing holes through it to the undercoating catching on fire and smoking the whole time, yeesh), including the rear seat latch hook that was cut off by the previous owner. Got the steering shaft extension done, got the fuel tank mounts all done as well.

Topped off the rad and PS. Got it fired up, fan works, took it for the first spin in God knows how long. Will probably change the oil and grease the u-joints.

Need to adjust the trans shifter, as it hits the radio now in 1st gear, and I have to hold it in order to keep it from popping out. Would like to weld in the rocker panel angle iron to pretty it up, but that's more of a nice to have. If I have time to whip up a simple new rear bumper, I will, but I may go back to the big ol' swing out if it comes down to it.

If I could keep the thing from pulling slightly to the right all the time, it would be cool, but ah, details.

9 days until URE.
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Adjusted the bend to the shifter - actually broke the old weld when attempting to bend it, so I had to throw some hot boogers back on it. Then I welded the angle iron to the rockers to cover up the ugly cuts (still need to do some seam sealer to make it look less terrible), and put the swing out tire carrier bumper back on. Will post some updated pics when I finish the seam sealer!

Had to replace a few old rad hose clamps, replace cig lighter fuse, and "adjust" some radio wiring that was causing issues.

May go ahead and mount the LS front seats, or may wait depending on free time.

One last thing I'm doing is replacing the cherry bomb vortex muffler. The vortex has an extremely annoying drone at like 1800 rpm, 2200 rpm, 2800 rpm, etc, haha, just has these spots where am usually cruising where it's just awful. This is what happens when you watch the chase scenes in "Bullit" while you are muffler shopping :blackeye: Going with a regular ol' turbo style muffler to quiet it down.
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I really need to jump on here more. From the few texts you sent me and then reading all this, man you had some serious scope creep.
That's a bunch of work. I totally agree tho on the want to drive cool old trucks on the trail and can get on the highway too. #notaJeep Why I also own a Scout too. ;)
Eventually I see you getting a decent enough suv that can haul a light enough trailer to tow your junk farther than uwharrie so I can take you to some of the places I wheel.
It aint so much about breaking as it is comfort driving back home. Hell, I drove to Harlan, KY in my isuzu, wheeled all weekend and drove home. Thats a bear of a trip!.
Hope to see you soon again brother. Good work.
I did the loud muffler route myself. It lasted maybe a month, running a turbo now. Still a bit loud but I am a bit hard of hearing anyway.
Got the muffler done and buttoned everything up for the 2 hr drive to Uwharrie on Thurs. Wow, the turbo muffler is much nicer!!! Now I can hear the typical manifold donut gasket leak up front :lol:

Drive was mostly uneventful but I will say I am ready to take this thing somewhere to figure out the pulling to the right issue. Developed a new vibe at >55mph which I think is just the rear driveshaft CV asking for grease. Also my power steering at idle just stinks and I need to figure something out with that eventually too.

Made it to Uwharrie, everything seemed to be running as well as it was going to. Buddy and I woke up early to join a Nissan group for a trail clean up on Friday morning. At some point, my electric fan stopped working and I nearly overheated a few times. We determined it to be the ignition on source. I picked a bad wire to use for that. So we spliced in a new connection to the battery and figured we could just disco that when done for the day.

In the midst of all that, while I was pulling off the main trail, I noticed my braking was getting super soft. I asked someone to watch my driver front brake line and eased into the brake and it was obviously leaking :crybaby: The line was leaking at the lower fitting. I think it must have gotten bent or stretched but it had definitely failed. So we spent about an hour and a half digging for things to repair that. The guys happened to find a fitting for the hardline and a plug for that fitting and thank God it held pressure. Big thanks to trooper buddy Dylan W and his buddies in the Nissan crew. They were awesome. I made it back to camp and parked the trooper and tried to figure out how to salvage the weekend.

We spent the rest of the afternoon trying to find something at the parts stores in the surrounding areas that would work, or someone to make a new hose, or someone to repair mine. No dice. Frustrating. Being 10mmx1.0 at one end and 7/16x24 at the other made it difficult. I decided to use my buddy's truck and trailer to drive the trooper back home the following morning.

After dropping it at the house, I turned around and drove back to Uwharrie, and we just relaxed and did some bunny slope trails with my buddy w/ all 4 of us (all 6'+ and 200lb+) crammed in his 1st gen 4runner :lol: He's got a SAS'd 86 with dual cases and 35's and lockers. It could have walked every trail out there with no drama, but we wanted to be smart since we were just out there solo. I drove it a little and I loved the deeper gearing.

Anywho, I just ordered (3) new -3AN brake lines with a 90* at one end, (3) 10mm to -3AN adapter fittings, and a pair of -3AN x 7/16 banjo fittings for the waggy calipers. Now, if a line fails, I have a spare. I want to eventually reconfig the front brake line system and just run a single line down to a T and hardline across the axle with some short hose at the ends to connect to the calipers. Keeps everything tucked out of the way. But for now the traditional set up will do. Once I have the brakes fixed, I'm going to see what I can do about the pulling issue.

I think after Fall Zu-wharrie in a couple weeks, I'm going to focus solely on finishing the samurai and then focus on addressing all of the trooper's remaining issues and gremlins - gearing, street manners, the steering, the motor possibly overfueling, the lack of parking brake... etc. It's turning into a pain to drive on the street and a pain to wheel and that's kinda the opposite of what I'm after!
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Fall Zu-Uwharrie meet was good. Didn't wheel as much as I hoped, just went out once for about 4 hrs, but the trooper did 3000% better while I was out there. New brake lines good. Got some grease into the rear driveshaft CV joint which allowed me to go at least 60mph. Front locker didn't want to engage, but that's ok, just need to adjust the cable. Didn't stop me on anything.

Lorenzo got some photos and videos in the uwharrie forum. We noticed that I'm getting a good amount of droop out if the front these days:


I measured it at about 7.5-8" droop and 3-4" up travel. Not too shabby. Once I can get it a few inches lower and maintain that up travel, I'll be happy. Want to get rid of the offset ujoint up front as well at some point.

Stuff to work on:

Squeaks and creaks. Re-torque body mounts and see if there are areas where the rockers and sliders are making contact and see what I can do there.

Fuel in oil. I did a compression check, and although it's not fantastic, (~13x psi to ~150psi) I think I had a slightly >10% difference between the lowest and the highest cylinder, but not way off. But considering what this motor has been through, that's ok. Since nothing is way off, it leads me to overfueling. I got 12mpg the past few weeks driving on the highway to Uwharrie and wheeling. That's a bit low, considering I stayed at 55-60mph. I'm going to grab a OBD1 bluetooth doodad to run data directly to my phone, instead of having to bring a laptop in the rig. I should be able to adjust the fuel pressure to help this a bit. We shall see!

Alignment. I need this thing to track straight, instead of merging toward the passenger when i left off the wheel. May need to refresh suspension bushing in the front.

Steering assist. The steering sucks at idle, I mean you could barely call it "power steering". And when the front is locked, forget it. I may see about grabbing a modifiable valve for the pump to juice up the output a hair. The one in my pump looked like it would auto adjust based on pressure. I don't want to do ram assist until I have the rest of the front suspension figured out, because I'll probably be moving mounts and things around.

Exhaust. May throw a resonator or something on to calm it down some more, and also going to fix the exh manifold donut gasket.

In the meantime, got gremlins to chase in the samurai, and lots of work left for it. Got OME rear springs all around, 31s, wheel spacers and OME shocks mounted. Would love to hit uwharrie one time open/open and manual steering just for the experience.


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