bobm
WTF, WTF, WTF!!!!
Tighten them U bolts after 100 miles or so. 
What did you do to your pig today? (1 Viewer)
- Thread starter ABQIRONPIG
- Start date
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In a perfect world the shackle would be somewhere between 90° and 45° at ride height.
At full drop the shackle should not go past 90° (to avoid inverting) and at full compression the shackle shouldn't go past 45° (again to avoid inverting)
These trucks that you see with shackles at or near 45° or 90° at ride height are going to suffer in ride quality and performance.
The how you get here is a little more complicated.
RUSH55
SILVER Star
Should be at least 90°, and yes, it might possibly settle enough over time or with some added weight, to get there or better (more outward angle). 60° - 80° is pretty ideal as the spring is in an area where it is more free to move outward as it flattens - as far as leaf spring suspension goes, this is where you’ll get the best ride quality.
At that little bit of negative angle you have going on there at the moment, there is an increase in forces transferred to the frame that the springs would otherwise handle, leading to a rougher ride and could eventually lead to frame cracks.
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I’m always reluctant to get too involved for fear of internet arguments with dirt road tailors that want to scream about internet armchair keyboard pricks, so with that said I’m not claiming I’m right or anyone did anything wrong just a couple guys enjoying morning coffee talking about theories.
You want to measure the angle between the shackle and a line that intersects the spring eyes, that is the angle we talk about not necessarily the seen angle. Guys like Rush can spot a shackle angle that’s too steep form a picture because he’s familiar with Pigs but it would be hard to call that exact angle. I agree it looks too steep in that photo and the ride would suck, springs settling is something they do but IMHO that shouldn’t ever be your plan “A” to solve a problem.
Shackle angle is very tough on a pig unless you’re willing to make big changes, you have two fixed points on the frame for the spring eye and shackle pivot, you have a fixed length for your shackle (I know you can buy or build different lengths but more on that later) and you have the two measurements of your springs (for us that have arched springs) it will be the minimum dimension at full droop and maximum dimension at full compression. If you punch those numbers into your online geometry calculator and you use a fixed shackle length around 3
“ to 4” you see that it is not possible to hit our 90 to 45 degree angles. For me I needed a 6” to 7” shackle length to get me comfortable margins with good ride quality, we obviously don’t want a 7” shackle hanging down in the front of our pigs even if we were willing to cut and rotate the balls to fix the caster numbers so things like spring sliders and reversals start to make sense if you plan to drive your pig off road and want good ride and drivability on-road. Lots of “rule of thumb” going on here and I don’t want to argue about 1 degree differences or if they even matter for what most of us do with our pig’s down here in the sty but I think we can all agree a 90° +/- a few at ride height is not ideal for either on or off-road.
You want to measure the angle between the shackle and a line that intersects the spring eyes, that is the angle we talk about not necessarily the seen angle. Guys like Rush can spot a shackle angle that’s too steep form a picture because he’s familiar with Pigs but it would be hard to call that exact angle. I agree it looks too steep in that photo and the ride would suck, springs settling is something they do but IMHO that shouldn’t ever be your plan “A” to solve a problem.
Shackle angle is very tough on a pig unless you’re willing to make big changes, you have two fixed points on the frame for the spring eye and shackle pivot, you have a fixed length for your shackle (I know you can buy or build different lengths but more on that later) and you have the two measurements of your springs (for us that have arched springs) it will be the minimum dimension at full droop and maximum dimension at full compression. If you punch those numbers into your online geometry calculator and you use a fixed shackle length around 3
“ to 4” you see that it is not possible to hit our 90 to 45 degree angles. For me I needed a 6” to 7” shackle length to get me comfortable margins with good ride quality, we obviously don’t want a 7” shackle hanging down in the front of our pigs even if we were willing to cut and rotate the balls to fix the caster numbers so things like spring sliders and reversals start to make sense if you plan to drive your pig off road and want good ride and drivability on-road. Lots of “rule of thumb” going on here and I don’t want to argue about 1 degree differences or if they even matter for what most of us do with our pig’s down here in the sty but I think we can all agree a 90° +/- a few at ride height is not ideal for either on or off-road.
Yes I'm talking about you @TachedOutOffRoad dragging me into your arguments with the Trail Butcher. #neveragainyoudick
Pigeaten
GOLD Star
You mean Richard
Pigeaten
GOLD Star
I remember my front shackle looking a little wonky, but have no pics, its in Tx, can’t remember what it was. Has OME HD susp.
Appreciate all the input and comments. Based on a number of pictures across my own phone and the interwebs, I see that the optimal position is indeed somewhere between 90-45 degrees forward. Since this Dobinsons lift kit is supposed to be made for the FJ55…which included 3 degree caster wedges…i will reach out to Dobinsons and Ozark Overland Outfitters where I bought them to get some input.
Pigeaten
GOLD Star
Or talk to @TachedOutOffRoad
You should definitely tell them that you "read on the internet" their system is not correct and point them to this thread so they can come and convince me that I am wrong...
No just kidding you totally should not do that!
bobm
WTF, WTF, WTF!!!!
HE SAID DICK 
RUSH55
SILVER Star
I would expect a kit from a name like Dobinson to be a little further ahead than something like Rough Country when it comes to the front FJ55 suspension. The SUA aspect must be the stumbling block, since it seems to be so difficult for these aftermarket suspension companies to dial in a formula that satisfies the several aspects that need satisfied. Essentially all they’re doing is taking a stock length spring and arching it to achieve the lift requirement.
There is also some mystique associated with FJ55 springs being “symmetrical” and reluctance by any manufacturer to veer from that.
So the reality is that the main leaves HAVE to be longer to satisfy the arch for lift and put the leaf eye out far enough for a satisfactory shackle angle. At this point, the problem then becomes, if the springs MUST maintain their symmetry, that the axle will move forward (with forward shackles). The rear is fixed, so any increase in spring length with corresponding centering of the leaf pack center bolt will move the axle forward. The only remedy for that is to drill the spring perches on the axle to recenter, or build the springs asymmetrically, with increased length to the front. And yes of course, longer shackles.
Rabbit hole
Needs a winch, a great big heavy winch.
More complicated....
The problem with the pig suspension is it never had very much travel and with that limited travel it's always had a shackle inversion problem..
The shackles are too short.
This has created an entire industry of anti-inversion shackles, slightly longer anti-inversion shackles and whatever other magic potion somebody has dreamed up to solve that issue...
Bottom line yes it could be done but.... A manufacturer is going to have to be brutally honest with their customer base and convince them that they are not trophy truck drivers racing Baja and don't need more than a couple inches of travel to do everything they are likely to do with their mostly stock Toyota Land cruiser. Then they would need to build that suspension with the longer main leaf to put the shackle in the middle of its range at ride height then build a bump stop to limit suspension up travel to prevent that shackle from inverting.
A suspension kit that honestly advertises 4 inches of travel on a 3-in lift kit would be laughed out of the industry so unfortunately it's easier to stick to your marketing wank like internal bump stop shocks and tell your customer those springs will settle and the shackle angle will improve just give it time.
FYI I've seen with my own eyes guys take pigs places they shouldn't have gone and come out the other side smiling with bone stock suspension and tire size...
The Dobinsons FJ55 lift kit advertises it as a 1.75” lift from stock so they weren’t trying to do much. The last three years at the PP’s once I was loaded down with gear the old tired springs were literally flat and the tires were tucked up pretty far. Needed to do something.
bobm
WTF, WTF, WTF!!!!
1 more question?? I have seen it before and no intent on your ability . Did you grease the bushings inside the bolt hole and on the outside of the bushing during install 
. Did you grease the bushings inside the bolt hole and on the outside of the bushing during install bobm
WTF, WTF, WTF!!!!
When you install your leaf spring bushings you need to lube the outside of the bushing and the inside where the bolts go through. Sometimes this is overlooked and the springs won't cycle. Poly or rubber they need to be lubed or the springs won't flex at all or normally. Capiche 
bobm
WTF, WTF, WTF!!!!
Greasable shackles only lube the inside of the spring bushing not the outside that contacts the the spring
