a different caster plate (1 Viewer)

[landtank]

Tools r us, I got it! I was pretty much through tell you it escaped me and it clicked. But I think it's more prevalant during a flexing situation isn't it.

And did you notice the panhard is on the wrong side and also raised off the axle. The panhard is my next challange.

 

[Tools R Us]

It's a down under truck, right hand drive. The drag link is raised with a high steer arm bracket and the panhard is raised the same amount at the axle.

The effect is most pronounced on the droop side in a flexed situation, but most of the time your going very slow when flexed, so it's not a big deal. Where you will feel it is at speed, drive a stock configuration truck at speed on a ruff road and it will feel like it floating over the holes. Then drive a lifted one at the same speed, it will feel like it's slamming into the holes, you will feel a forward g force along with the up and down. This adds greatly to the stress loads on the suspension, blamed for a a lot of the suspension bracket breakage down under. This is the effect that LCWizard is talking about the 4plus bracket drop solving, the drawback is the loss of clearance behind the wheels. With the arms on top mod you gain clearance under the axle and don't loose at the rear of the arms, best of both worlds.

All of the people that have done the arms on top mod have raved about how much better the truck handles and climbs. It looks like you would need about 5"+ of lift to do it and may need to slightly limit the up travel. The only thing that I see that may take some work is fitting the swaybar, it would need to mount to the top of the arm and may interfere/rub on the arms.

 

[semlin]

Another thread on arm flip.

http://www.4wdmonthly.com.au/forum/index.php?board=18;action=display;threadid=9110;start=0

wow that is quite a truck on that thread. the panhard mount torn out of the frame particularly impressed me. cranky cruiser appears to be at or just past the limits of 80 lifting before you become a trailer queen. he just needs some portals and to go from 35s to 38' and I think he's there.

 

[ats4x4dotcom]

Alot of work to recreate something that already gives the 5 deg you needed really, and for that much trouble, i would of moved the mounts for the A arm flip, making for a truck that drives much nicer again, and wont get cought up on the arm angle when trying to climb steps etc.


And everyone should fix the castor on their truck, if they lift it.

 

[landtank]

Alot of work to recreate something that already gives the 5 deg you needed really

No work at all, it was fun!

 

[Rich]

Alot of work to recreate something that already gives the 5 deg you needed.

I figure it was more like a lot of work to IMPROVE what already existed.

Eliminating the need to cut off a portion of the existing brackets, eliminating the need to grind the arms, and, apparently to me, also eliminating the need to weld the plates looks to be a significant improvement.

 

[landtank]

Thanks Rich, and I'd like to add, the ability to tune the plate to your specific needs.


Anyway, just got back from having the truck aligned. Pretty much what I expected, I was a little under target.

In case you missed this, I didn't anticipate gaining lift from rotating the axle. This happened do to the rotation taking some of the bow out of the springs allowing the front portion of the wraps to support more weight. I saw a .75" increase and immediately knew I should have sdrilled at 6*.

The final numbers are as follows:

Left tire caster 2.2*
right tire caster 1.3*

The left value is fine but the right is .7* under minimum. This kind of goes with the territory of developement. I am pleased with the out come and the truck drives better than I can ever remember.

On a side note: when I compare the pre plate numbers with the post plate numbers there is some error between the cross caster numbers which shouldn't have changed and the rear axle numbers are also different. So there is some fudge factors as to what the guy on the rack is seeing or his talent at setting up the truck.

 

[concretejungle]

Rick, why do you think one side is that far different than the other? In theory, shouldn't they both be the same? Perhaps it's to deal with the crown in the road, maybe?

 

[landtank]

Pre plate cross caster (R & L compared) was .2*
Post plate cross caster is .9*

This along with the different rear readings makes me think that the truck was poorly setup this time.

The .2* is what I'd expect but the .9* seems too large and is actually out of the acceptable range.

I'm not going to sweat it but wanted to post up the numbers for those who might be interested.

 

[e9999]

am I remembering correctly that an actual 4" of lift should give about a loss of 4 degrees - theoretically?
what was the caster when stock on yours?

 

[landtank]

My original numbers where:

left -1.8* right -1.6*

Hub center to fender 22.5"

The 1 inch, 1 Deg is only a rough idea of caster. Because as you raise the vehicle each additional inch will yield a slightly increased amount of error over the previous inch do to the arc the axle is travelling.


I have Slee's 4" springs and needed 6* of correction.

 

[e9999]

My original numbers where:

left -1.8* right -1.6*

Hub center to fender 22.5"

The 1 inch, 1 Deg is only a rough idea of caster. Because as you raise the vehicle each additional inch will yield a slightly increased amount of error over the previous inch do to the arc the axle is travelling.


I have Slee's 4" springs and needed 6* of correction.

do you know what it was when stock -before the lift?

22.5" is only 2.5" lift over stock, though, no?

 

[landtank]

Nope, back then I was going with the common law of what to do.

I don't know what stock is on the hub/fender measurement.

 

[Tools R Us]

Nope, back then I was going with the common law of what to do.

I don't know what stock is on the hub/fender measurement.

About 19.5"

 

[landtank]

About 19.5"

Excellent, then I'm at 3.75" of lift.

 

[e9999]

Excellent, then I'm at 3.75" of lift.

mmm....

u sure?


(my stock rig was more like 20" in front btw, but close enuf...)

 

[landtank]

I think so, I'm now at 23.25" and if stock is 19.5" then thats 3.75" over stock, right?

 

[e9999]

I think so, I'm now at 23.25" and if stock is 19.5" then thats 3.75" over stock, right?

sorry, must have misunderstood the 22.5" you just mentioned.

 

[landtank]

My original numbers where:

left -1.8* right -1.6*

Hub center to fender 22.5"

The 1 inch, 1 Deg is only a rough idea of caster. Because as you raise the vehicle each additional inch will yield a slightly increased amount of error over the previous inch do to the arc the axle is travelling.


I have Slee's 4" springs and needed 6* of correction.

Those were my original numbers prior to the plates. After the plates my truck now sits .75" higher.

 

[landtank]

Found my caster error. Thought about this all night and realised what the tech had done. The one possible contact area with this system is the Tie rod clamp against the leading arm. Now the manual specifies that the clamp be positioned at 60* +/- 10*. Well he didn't and the clamp interfeared with the sweep and I'nm sure is the reason for that one side reading low. The other clamp was positioned properly.