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

219K views 833 replies 40 participants last post by  paulevans76 
#1 ·
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:

Index:

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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#4 ·
Thanks yall. Just FYI I used to be pretty into the whole Isuzu thing back in the day. Between '99 and '08 I had 3 troopers. A white 91 SE 2.8 5 speed, that had a 2" lift and 33x10.50's, an 86 2 door with a 2.3 that was more of just a fix and drive, and an 88 2.6 5 speed that I did a normal leaf sprung SAS on--well I got about 90-95% through and couldn't seem to figure out that last little bit. The steering and front driveshaft had me up against the ropes. I sold it to Joe D, or a buddy of his, and hopefully they make something cool out of it eventually.

So anyway, today I went to work on the rear spring swap. I ordered OME CS010R springs - heavy duty dakar packs for an 1st Gen IFS 4 runner. Specs seemed to indicate that they would work. I was looking for something that would match the lift of stock trooper packs. I know some yota guys will swap trooper springs on their trucks for 3" lift, so I figured maybe the reverse would be true going the other way. These OME springs are supposed to give about 2.25" of lift to a toyota, and they have a higher spring rate, which I hoped would work with the heavier trooper.


My measurements were
Front eye to centerpin (along arch):
Stock trooper: 21 3/4"
OME CS010R: 20 3/4"

Centerpin to rear eye (along arch):
Stock trooper: 25 3/8"
OME CS010R: 26 1/2"

Total length front to rear eye (along arch):
Stock trooper: 47 1/8"
OME CS010R: 47 1/4"

Sweet. Just need to offset the centerpin mount 1".

Luckily the spring pads on my rear axle have a few options:

One hole was 1" forward, which shifts the axle 1" back. Perfect!

The result:


A bit of lift, damn it! I reckon it will settle a bit over time, but I was hoping it would be lower. I should have taken measurements of frame height and stuff, but I forgot to do that until I already had one spring mounted. We will see what happens with it over the next few weeks. I will probably just need to remove the overloads to get it where I want it.
 
#5 ·
Impressions of the springs after a quick drive- wow, the trooper rides really nice now. I'm going to remove the overloads ASAP to drop it about an inch, and then see how they settle.

I'm glad that the spring size matched so well. I think this really opens up some options for leaf sprung 'zu rear lifts. Many of the hardcore off road toyota suspension companies (allpro, trailgear, etc) do a 56" rear spring and a 47-48" front spring (based on the rears up front setup that so many toyota guys like), so I think that running an allpro or trail gear front spring--I'd probably go with the heavy duty versions for the extra spring rate--would work on the back of a trooper really well. A stock length rear lift spring for 84-89 pickups and 4runners would probably also work, and you'd be looking at trailmaster, skyjacker, rough country, brands like that, and a 4-5+" lift spring for 1-2+" lift on a trooper.

Back in the day in my IFS rigs, I always thought that running a stock toyota spring SOA on a trooper would probably net about 3" of lift, but I never got the chance to try. I'd probably run an extra leaf or two mixed in for spring rate, but it would be much flatter than the stock spring, thus avoiding the excessive lift in the rear.

Enough rambling. Glad to be back wrenching on a good ol' trooper.
 
#6 ·
Huh. Cool rig and good intel on the springs.

I am trying to figure out how to do a low lift spring over on my Trooper. I am planning a couple of things to minimize lift:

1. re-drill the front spring hanger and move the hole 1 to 1.5" closer to the frame (.5 to .75" drop),
2. Bottom of spring mount flush with the top of the axle housing,
3. Pulling both overloads out of my Trooper OME Dakar pack. Bradzipple seems to think this is a bad idea. (1" drop),
4. Shortening the rear shackle as much as I can without loosing travel (0.5" drop),
5. If necessary, french the rear shackle hanger into the frame (0.5 to 0.75" drop).

Might be worth taking a look at those points as well if you are trying to loose some lift...
 
#7 ·
I love your trooper, chuffer. If I'd bought a stock rig, I was probably going to copy quite a bit of your SAS set up.

I don't think losing the overload will do anything negative unless you are loading to max capacity. If you ARE loading it to max capacity or beyond, you could always look into an air-ride airbag system to give you some extra capacity when you need it.

I need to look at the front spring hangers again, but I think you're right and you can redrill the mounting holes a little closer to the the frame. You probably want to leave at least a half inch between the spring eye and the frame to account for twisting/movement of the spring/bushing. I am hesitant to go any shorter on the shackle as that will begin to limit travel and potentially bind the spring a bit or risk inverting the shackle (mine is only about 4-4.5" currently, and I think it's probably going to limit me). You can move the shackle mount an inch or so forward if you 'adjust' one of the gas tank mounts, and doing so allows you to run a shackle long enough to use all the available travel in the spring and maintain a good shackle angle.

If you were open to using different springs, you might have a few more less invasive options, but I'd probably try to make the OME's you already have work, too. They are a high quality spring for sure, and although they aren't that expensive, they aren't free ;). You could always cough up 500 or so clams for a custom set of Alcans and get exactly what you are looking for.
 
#8 ·
Yeah, I looked at Alcans and having some springs locally made. To get what I was looking for (spring under and about 6 inches lift) was pricing out at $750. I figured I can do lots of cutting and get Brad to do a lot of welding for that price...as always I will be cuttin the piss out of things and then he puts them back together...

The front hanger is pretty tall. It looks like there is room to raise, trim it and still have room to clear flex. What makes this process (slightly) more complicated is that there are a couple of holes on mount that would need patching and I think the "nuts" are integral to the mount. Not really big issues, just two more steps along the way. 5" shackles are my target. I am at 6" right now.
 
#9 ·
Congradulations on your purchase, and welcome back to the fam. You definately have an eye for beneficial tweaks. They all sound really reasonable, and I completely agree with your ideas on lifting for need more than just to have a extremely lifted rig.

I'll be keeping an eye out for your upgrades.

By the way, some of the hilux guys here in Chile take out the over load spring on the leafs but they say that the axel tends to rotate more, so many add anti pitch (rotate bars). Still, they sat that it depends on the strength of the pack as a whole as well. Factory springs tend to be softer on the hilux's and therefore taking out the oveload reduces their resestance. I don't know that that would be the case on w/ the troopers.
 
#10 ·
I can see running into problems if you removed one of the normal leaves in the pack, as that would affect the overall spring rate quite a bit, but the overload doesn't really do much until you are loaded down. As long as you bumpstop the suspension at the point that the leaf is flat and don't let it go negative, removing the overload shouldn't have any affect on ride, axle wrap, or spring life. I could be wrong, but those are my thoughts on it.

I do already have mounts for a traction/anti-wrap bar under the trooper, I'd just need to make the actual bar and a shackle. I'm hoping that the new springs will help control wrap on their own, at least for a little while. I'll know what I'll need for sure once i get it out on the trail.
 
#11 ·
I understand what you're saying, and as i mentioned, I'm not real sure how much of an effect it would have on your HD springs, or on Trooper springs. Even though, from what i've heard, the trooper springs seem to be very soft. Not weak, just have good ride. The hilux guys have mentioned the warp occures mainly during heavy exceleration, and clearly in instances such as heavy acceloration while climbing with the full weight falling toward the back axel. If you understand what I'm saying.

Once again, I've never experienced this, nor am I saying that, this will happen. Just trying to give some food for thought so that you guys can hopefully work out the kinks before various versions of fabrications are needed.
 
#12 ·
i got ya and I agree with ya ;) Factory springs are usually pretty great--economical, ride nice, and last a long time under normal circumstances. Putting them to their limits over and over, putting more torque to them through bigger tires, high traction situations on the trail, etc will definitely expose their drawbacks and fatigue them much quicker. A decent anti-wrap bar will eliminate 99% of axle wrap, and can allow you to run a set of softer or stock springs longer than you could without, but an anti-wrap bar and a good set of springs will more than likely last longer and work better than just one or the other.

I was hoping to get back at it today but it's hotter than hell outside and I'm still pretty sore from the yesterday. Because of work, I'm thinking it will probably be August before I can get out on the trail, so no big giant hurry.
 
#13 ·
Got the overloads removed and it dropped the rear down to a reasonable height. Front and rear of the side frame rails are almost even with a slight (~1/2") rake down toward the front.



Ride is cushy. Not too too soft, but not very firm. I need to look into new shocks all around and maybe stiffer coils up front, as I think quite a bit of the marshmellowyness is coming from up front. Eventually I'd like to get some sway bars for it for more stability on the street.
 
#14 ·
paulevans76 said:
Got the overloads removed and it dropped the rear down to a reasonable height. Front and rear of the side frame rails are almost even with a slight (~1/2") rake down toward the front.



Ride is cushy. Not too too soft, but not very firm. I need to look into new shocks all around and maybe stiffer coils up front, as I think quite a bit of the marshmellowyness is coming from up front. Eventually I'd like to get some sway bars for it for more stability on the street.
Do you know how much it actually dropped?
 
#15 ·
1.5", but that could be off a tad since i measured on grass.

I did some more digging while trying to figure out what new front coils to try, and found this pretty helpful for comparing spring rates of OME coils and leaf springs.
http://www.arbusa.com/Uploads/PDF/onlin ... urrent.pdf

It looks like the normal 'medium duty' 1st gen 4runner leaf springs (cs009r) have basically the same spring rate as the heavy duty trooper springs (cs029r), 217 & 216 lb/in respectively. The cs010r springs I have are actually 285 lb/in.

The coils I have up front are pro-comp TJ 4" lift units, with a 175 lb/in. I ordered up some rubicon express 3.5" lift coils, which have a 240 lb/in, so we will see what happens with those next week.
 
#16 ·
paulevans76 said:
1.5", but that could be off a tad since i measured on grass.

I did some more digging while trying to figure out what new front coils to try, and found this pretty helpful for comparing spring rates of OME coils and leaf springs.
http://www.arbusa.com/Uploads/PDF/onlin ... urrent.pdf

It looks like the normal 'medium duty' 1st gen 4runner leaf springs (cs009r) have basically the same spring rate as the heavy duty trooper springs (cs029r), 217 & 216 lb/in respectively. The cs010r springs I have are actually 285 lb/in.

The coils I have up front are pro-comp TJ 4" lift units, with a 175 lb/in. I ordered up some rubicon express 3.5" lift coils, which have a 240 lb/in, so we will see what happens with those next week.
Good job on the ARB/OME cataloge. I have the Rancho catalog like that too. It's a really good reference.

Thanks for sharing it with us.

I hope the springs work out how you like, and nice work, on find the info and ordering. No hesitation.... Wow! Wish I could decide so quickly on spending money.
 
#17 ·
No prob, sharing info is what these forums are about.

And I don't mind dropping a few bucks when its going to potentially improve the safety of my ride! I can always recoup some of the cost by selling the coils that are already on it.
 
#18 ·
Wow, I love this truck. :D

Would love to SAS my Trooper but I dont think I could do it!

Love it!

cheers
-Ian :blackeye:
 
#19 ·
imamonstertruck said:
Wow, I love this truck. :D

Would love to SAS my Trooper but I dont think I could do it!

Love it!

cheers
-Ian :blackeye:
Believe me ian, you could do it. With the guidance from the forum and a little study, plus a bit of welding/grinding/cutting practice, you'd have it done in no time. Well... if it's anything like my Daihatsu SOA project, it'll cost 2x's what you think, you'll drive it for 1 yr. it'll sit another year, and you will still not have it the way you want it. JK! :lol:

And I don't mind dropping a few bucks when its going to potentially improve the safety of my ride! I can always recoup some of the cost by selling the coils that are already on it.
I understand and agree completely.

As far as pics and sharing, your right about the purpose of forums, but we all know how challenging it can be to find time to do, share, and remember pics. So, thanks again!
 
#20 ·
Got the RE 3.5" coils in today. After maxing the hilift out at the front of the rock slider, I just had to remove the shock and the old coil slid right out, new ones slid right in. Even though the coil is supposed to be 1/2" less lift than the ones I removed, the higher spring rate (these are 240 lb/in vs the procomp 4" which were 175 lb/in) more than made up for it, so it might even be 1/2" taller. But, I kinda don't even care right now, because the ride is WAY WAY better. Brake dive is all but eliminated, turning feels more stable....would be better with some sway bars, but those will come eventually. All in all, these coils are much better suited for the weight of this rig. When i move on to getting this thing lower, I think I might mess with the coil mounts before I try to find a shorter coil...don't want to lose travel.

Today I also got a good deal on an open box stereo...the old sony xplod tape player currently in it is having issues with the radio reception, even though I replaced the antenna, and the cd changer wasn't working right anymore either. Upgrading to something with all the aux and usd inputs will be nicer.

Other stuff:

The front gears haven't been broken in on the trooper, so I started that process yesterday. Just drove around lightly in 4wd for 15 mins, let it cool off completely, and was gonna repeat that whenever I had time this week. Well, when i got back from my first little jaunt, there was a leak at the pinion seal, and gear oil was slung everywhere. So, I went by East Coast Gear Supply yesterday to talk to them about that and a few other things i want to get done while I'm out of country later this month through mid-August. They are going to pop in a new pinion seal, tighten things up, and see if that fixes it. They seemed a little concerned that there didn't seem to be much (any) preload and said they might need to tear into it if things don't get right after the new seal, shims and tightening everything up. If they end up having to tear it apart and rebuild it, I'll probably go ahead and upgrade the shafts and joints. They also looked the rig over and suggested a few extra gussets here and there on the front suspension, and I'm going to have them do that and also install me some air-bumps and limit straps up front and finish up the wrap bar in the rear.

Went by a local exhaust shop today to see what he thought about fixing up the exhaust issues- leaks galore, mostly in the flex pipe that makes up half the y-pipe (it's the off the shelf flex pipe). We are also going to see what we can do to adjust/modify the flanges on the manifolds that seem to always leak on every 2.8, do the new y-pipe, and run 2.25" exhaust front to back. This guy has one of the only mandrel benders in the state, so it should end up pretty slick. Price he quoted wasn't tough to swallow either. it will be AWESOME to not have to listen to the awful 2.8 trooper exhaust leak sound ever again!

I'm hoping to have all that done by the time I'm back in town in mid August, and then I can switch gears to reducing the body lift from 3" to 1". I think leaving that 1" in there will help to keep some bolts and stuff a little easier to get to, and the slight increase in COG will be negligible. Lots of stuff will need adjusting though. The sliders I should be able to cut off and weld a little lower on the frame, angle them down a little more, and be in good shape there. I'll need to adjust all the extensions on the shifters and steering and stuff. But the big job will be the gas tank. I don't really want to lower it back down, so I'm thinking of lifting the floor instead, or basically sectioning out the area above the tank, raising it up a few inches, box it in and seal it up. Probably leave it removable in case the pump quits on me.

Good times!
 
#21 ·
Sounds like you have some plans for the rig. I hope they work out.

Is your 2.8 turbo diesel? I have a 2.8 turbo diesel in my trooper, and I ran 2.5" and a high flow thrush muffler. While it's very quite, because of the turbo, it breaths really well. In fact, the exhaust manifold flange mount is 2.5" id on mine. So, I was just curious about yours.
 
#22 ·
I wish. It's just the 2.8 GM gasser. Gotta try to find a 3.4. I wish they still made the crate motor. This thing will be awesome with a little more power.
 
#24 ·
Thanks :)

Dropped it off today to the guys at East Coast Gear Supply, and they will be handling what is hopefully just a pinion seal replacement and not a whole front diff tear down, and also installing air bumps or stinger bumpstops up front (still deciding), throwing on a rear anti-wrap bar, front limit straps, getting the ebrakes working, and probably a few other things I think of. As I get updates from them I'll post up, but it will probably be pretty dead in here for the next few weeks. Work's sending me back to Angola until mid-August, and I'll be busy as hell with that and bouncing back and forth from there to Houston every week.
 
#25 ·
Man I tell ya, the rest of the world gets all the cool stuff. The 70 series land cruisers are like what the troopers should have been. They have a similar look, shape, split rear door (although the little door is on the left on the cruisers), and a radius arm/coil suspension with solid axles front and rear. Oh and a sweet turbo diesel engine. And lots of different body options (single cab/double cab with bed or tray, 2 dr troop carrier, 4 door wagon - aka the trooper clone).

Here's a shot I took out in front of my pad at the construction camp I'm currently working from (Ambriz, Angola):



A pickup and a beat up wagon. Looks familiar don't it?
 
#26 ·
paulevans76 said:
Man I tell ya, the rest of the world gets all the cool stuff. The 70 series land cruisers are like what the troopers should have been. They have a similar look, shape, split rear door (although the little door is on the left on the cruisers), and a radius arm/coil suspension with solid axles front and rear. Oh and a sweet turbo diesel engine. And lots of different body options (single cab/double cab with bed or tray, 2 dr troop carrier, 4 door wagon - aka the trooper clone).

Here's a shot I took out in front of my pad at the construction camp I'm currently working from (Ambriz, Angola):



A pickup and a beat up wagon. Looks familiar don't it?
I know man. Here in Chile they have some of the Really Nice brand new landcruisers too. They're not cheap here though. Chile also got the Nissan Patrol diesels too. Those have the same look in the back. That kinda boxy look with the split door thing. The motor options were better for the Landcruisers and the Patrols though. Just makes me sick. I don't have the cash for either. Plus, the Patrols are even rarer than my trooper. So, I don't want to go that parts road nightmare.

Still, I'm not complaining. My trooper rides better than the landcruisers typically do.

Guy down the street from me has a LC 70's, an 1970's FJ, a 98-2000 Patrol, and a 98 Toyota Hilux. All of which are pretty maxxed out. Off-road gear wise. I hate driving by his house, in my mildly modified Trooper. :cry:
 
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