NEWBIE Question! Rough Country Systems and Shackle Angles...

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hecrod

hecrod

40 & 930 Fanatic...
10 Year
Joined
Jun 25, 2012
Threads
15
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355
Location
Waltham, MA, USA
Website
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Hi All,

Been a member for a while as I scoured the net for my first FJ40. To make a long story short, I bought mine a few weeks ago and have some questions that I hope you guys will have some time to answer... (I'll add some more pictures later).

While I knew what to expect with regards to ride... this one seems to ride way too stiff. I know enough to know that the shackle angle looks to be wrong, and it is likely the main reason for the stiff ride (honestly, I never knew I would use seat belts just to prevent being thrown off the vehicle while driving the highway! LOL).

What are my options here? Would a shorter shackle do the trick? I'm not opposed to dropping the LC a couple of inches if that helps. If so, which shackle should I go for (it's a rough country suspension system)? Anything else wrong with what you see in the pictures?

Thanks in advance for the help!


Hector
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Shackle angle looks fine. The angle will only affect ride quality if they are completely extended or laying up against the frame. Ride height alone doesn't have much affect on the ride. Thick, heavy springs with few leaves is the problem.
Shocks can cause a rough ride but I think you are ok with what you have.
 
Maybe check the shackle bolts for over tightness. That's a common issue. If they are good, go for the leaf removal.
 
Ok. Thanks for the input... much appreciated.

So I will do the following over the next few days:

1. Remove a leaf (next to one from bottom)
2. Put some anti friction pads (will get from "auto and truck springs"...)
3. Check for torque on u-bolts (less than 86 lbs), and
4. Leave shackles loose

I still read many people writing about "proper shackle angle" being about 45 degrees or so. Mine is clearly closer to 90. What could I do to adjust the angle?
 
Your angle sucks
Throw a couple hundred pounds in your rig and flex them out. Your springs are not known for the soft ride
 
I would check the bolts on the shackles first before I removed a leaf. Also, you said something about checking the u-bolts for torque. I hope you don't mean to loosen them thinking that will affect the stiffness of the ride. If I remember correctly, we torqued mine to 95 lbs.
 
I ran the RC 4" lift springs for a few years, with longer than stock shackles. The ride was stiff, and rough but nothing like you are talking about. On the street it was stiffer than the 40 year old stockers but very bearable, off road it did want to hop on steep powered climbs. They did soften up with use, I could tell they were better with each trail ride.
 
chevurai said:
Shackle angle looks fine.
Click to expand...

it's not - you do not want 90 degrees against the frame as pictured

chevurai said:
The angle will only affect ride quality if they are completely extended or laying up against the frame.
Click to expand...

incorrect - shackle angle will determine how well the shackles can give when the springs are compressed - if you go over a bump with 90 degree shackles (no matter the length), the truck will pogostick
 
DSRTRDR said:
it's not - you do not want 90 degrees against the frame as pictured



incorrect - shackle angle will determine how well the shackles can give when the springs are compressed - if you go over a bump with 90 degree shackles (no matter the length), the truck will pogostick
Click to expand...

Thanks Claudia.

So, would it be correct to say that by removing a leaf, the truck will "settle" a bit, pushing the shackles out from underneath, resulting in a better angle? What other steps do you (or anyone else for that matter!) recommend I take to improve on the angle?
 
Those springs look pretty new. I would run it for awhile, maybe some extra weight in it and see what happens. I have Rough Country on two of mine. One a P.O. install and one I did. The one I did rides nice but it took a year or two before they softened up. I do wheel it some so that helped free them up. The other one, currently wrecked, rode ok, but not as flexible and a little stiffer. I have put maybe half as many miles on it.
Since you just got the truck, as long as everything if safe on it, drive it for awhile to get used to it and figure out what you want to do. So many people get a Landcruiser and don't enjoy ity before they start taking it apart! If it's running, then run it! We need more picks of the truck. Looks good from what we can see.
 
Do the shackle bolts have nylock nuts?

I don't see where you're going to be able to remove a leaf from those springs.

You're not going to like the price, but you could have Alcan make you some springs that would be nice compared to those and they could be made 0.5-1" longer to improve your shackle angles.

After driving around in my buttery SOA all weekend I really feel for you SUA guys. :steer:
 
DSRTRDR said:
incorrect - shackle angle will determine how well the shackles can give when the springs are compressed - if you go over a bump with 90 degree shackles (no matter the length), the truck will pogostick
Click to expand...

Incorrect. The shackle angle has very little effect on spring rate as long as the shackle can swing. It is only when the spring hits the frame that it can no longer compress. It is the weight to spring rate ratio that determines ride stiffness.
 
Shark56 said:
Since you just got the truck, as long as everything if safe on it, drive it for awhile to get used to it and figure out what you want to do. So many people get a Landcruiser and don't enjoy ity before they start taking it apart! If it's running, then run it! We need more picks of the truck. Looks good from what we can see.
Click to expand...

Ohhhh... I've been driving it alright. Drove it for about three hours this past weekend. It's just that I have two problems:

  1. The ride is so rough, that my wife is already finding excuses why not to ride in it...
  2. The truck is too tall!!! I can't even drive it to work as it won't fit in the parking garage! I've taken down the roof rack... and it still won't fit. I tried it! By the way, parking garage max height is stated as 6'8"!

So I have two problems... that may be linked. Need to think about this a bit longer.


And on the shackle angle discussion, is there then no agreement? Some say it affects the ride and some don't? Someone out there with some evidence one way or the other?


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I'm in the does not affect ride quality camp. As the spring compresses it effectively gets longer, so the shackle swings away from the spring. That doesn't change if it happens to be straight up and down.

You have very arched lifted springs on a short wheelbase vehicle. It's going to ride very stiff. I would not remove any leaves. That lowers the load carrying capacity.

You could try lower lift springs.

That's a very good looking FJ40. You might consider returning to stock springs and smaller stock size tires. That always looks good on a 40 in good condition.

If it's too tall, the first step is to take off the roof rack.
 
Hate to break this to you but you have a short wheelbase, spring-under, leaf spring truck, with (in my opinion), over-arched springs (I have the same thing) in order to get the lift. Yes there is some additional length there too, but it's a recipe for a rough ride. I know, I have a 71 FJ40 with a Man-A-Fre 4" lift (rear is 4", front is 2.5" plus a shackle reversal) and mine rode rough and still does. It's better since I got a tire carrier and I have a 35" tire and wheel back there, plus I flipped my rear springs. I have adjustable Rancho shocks set to "1" (softest setting). All this helped somewhat, but it's really not too much of a difference. I know to lean forward when hitting certain bumps... :rolleyes:

Really no amount of sandbags, wheeling, whatever is going to help much. If you REALLY want a much smoother ride (and this is relative) go spring over and either run custom Alcans or a mix of Chevy truck / FJ60 / whatever plus greasable shackles teflon spring plates all the sexy stuff. Personally I'd do the Alcans and be done with it. I should have gone this way to begin with.

Oh and BTW... nice 40!
 
Load it up with a lot of weight and go down a rough road. If the springs are not broken in it will help a lot to break them in some, probably not enough to make your wife happy, but it will help. Going down paved roads does not brake them in very fast, need to work them out. Many people have had this issue with new springs and breaking them in did help, many posts about this just search for "sand bags".

You would want to ride in a spring over axle fj40 before going that route, most spring overs use the old warn out stock springs and that is why they ride smooth, but they add a tipsy feeling and a lot more height and that will really not make your wife happy. Bottom line these were rough riding vehicles from the start.
 
Ok... so here's my first step. Got it up in some ramps and will leave it there overnight. Will repeat the other side tomorrow into the day after.

Notice the shackle angles... they didn't move much... Would you guys expect them to move a bit more???

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