Uneven LCAs help

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Freezerman

Freezerman

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We rebuilt the front suspension on our 72 Dart, didn't seem to have problem before but not sure. Now when trying to set ride height I have to crank the drivers side in most of the way and the pass side about 1/2 way where I would expect it.
With the height roughly equal the drivers control arm is at least 1/2" lower. If I jack up the k frame the pass side is several inches of the ground before drivers side comes up. If I jack the rear up the pass side tilts down.
I can't see any movement in the rear t-bar mounts. Do t-bars get weak or do I have a problem with driver side LCA?
This pic is of driver side
 

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Twisted frame ? May have hit a ditch in a past life.

That or you run a LOT of HP !
 
Thanks no ha. Just a 318 with a little extra. Everything seems square, you can see how far up the adjuster is. The other side barely comes over the top of the control arm. Yes I did on the bushing question. Then I took the tension back out of the suspension and ran the adjuster all the way back out to check the clocking again.
One thing that doesn't seem right is if you look at the adjusting bolts from the front, the pas side angles in a little where the drivers side points almost straight down.
 
I second making sure the spindles are loose I had originally asked if it was a slant 6 but see it's a 318.
 
I did have the LCA bushing bolts loose first then tightened after on the ground. Do they need to be loose while adjusting too?
What would make the control arms uneven? I don't remember there being a problem before we had it apary.
 
Have you switched T bars side to side? Personally I think this business of worrying about having the car on the ground before tightening things up is bullshit. There's no mention of it in any of the shop manuals, Motor's or any other thing. The factory sure as hell didn't do that.
 
I had the same issue on mine, I just pushed down further on the drivers and slid the bar in. Not the first time or the last, just how it's geometry works.

It's OK bro.
 
Yes, the LCA bushing bolts (spindles) need to be finally tightenened AFTER the ride height is set. If you tighten them during anytime before, the rubber will be twisted in the bushings, producing an artificial spring torque, and then the bushings will slip or the rubber will tear and the ride height wil change as that artificial spring torque is lost.

It kinda sounds like one of the T bars is clocked off 1/6th of a turn relative to the other. The LCA's should be hanging down at a pretty steep angle when inserting the T-bars. The passenger side LCA seems to be the issue (it sounds much weaker than the driver's side, per your opening post description, and the driver's side is therfore taking almost all of the front end's load) and the passenger side LCA may not have been hanging down at a steep enough angle when the T-bar on that side was inserted.

Edit to add: And on the question of locking down the LCA bushings after the ride height is set, this is a known procedure that is common to all such LCA arm designs where the bushing is locked in, both for double, unequal length control arm types and McPherson strut types. I have seen it not documented in other factory car manuals like on certain Opel, Toyota, and Mitsubishi models, so am not surprised that it is not in Mopar manuals either.
 
Is it really possible to put the torsion bars in wrong? The only reason that I ask is because I'm in the process right now of rebuilding my front end ('74 Dart Sport) and the T-Bars slid in with ease. Did I just get lucky?

Thanks..........Ted
 
Wow OK lots to check. I did loosen both lower control arm pins and rolled car back and forth 10 feet or so, did help some with even out control arms, still 3/8" difference. Right and left are correct.
Interesting I thought the drivers side weak because I have to crank the adjuster in so far to get close to level.
There is a clocking on the bars? I thought if you drop the arms all the way and crank the adjusters all the way out, push the swing arms down to pins and slide the bars in. No?
Why when I lift the car and let the wheels hang the drivers side comes down so much farther?
 
I did, couldn't see any. I guess it could have cracked after.
 
Freezerman said:
Interesting I thought the drivers side weak because I have to crank the adjuster in so far to get close to level.
Click to expand...
When I read your symptoms, that fact that the passenger side goes down when you jack up the rear says that the passenger side is weak. I am thinking the passenger side is so weak that that the driver's side is being cranked all the way tight to take up almost all the front end load.

Freezerman said:
There is a clocking on the bars? I thought if you drop the arms all the way and crank the adjusters all the way out, push the swing arms down to pins and slide the bars in. No?.
Click to expand...
Sounds like the right procedure, but maybe something is a bit off on the passenger side clocking (indexing) of the T-bar.....I would be starting there. Is the rear of the pass. side T-bar set in right?

Freezerman said:
Why when I lift the car and let the wheels hang the drivers side comes down so much farther?
Click to expand...
Unless something is broken, then if there is not any real torque on the passenger side T-bar, the rubber bushing in the LCA is probably what is keeping it from dropping far; the bushing rubber can offer a lot of torque resistance. (Just try moving the bar up or donw a lot without the T-bar installed and with the bushing locked into place; you will need a pipe to torque it very far.) With the T-bar properly clocked (indexed) then the T-bar will overcome the rubber bushing torque and drop the arm properly as the car is jacked up, like it sounds is happening on the driver's side.
 
Just rechecked clocking on both sides. With the bump stops out, shocks disconnected and tbar adjusters backed all the way out, both sides hang very close to same. It sounds like I might be having to save up for new torsion bars?
 
DusTed74 said:
Is it really possible to put the torsion bars in wrong? The only reason that I ask is because I'm in the process right now of rebuilding my front end ('74 Dart Sport) and the T-Bars slid in with ease. Did I just get lucky?

Thanks..........Ted
Click to expand...

There is a left and right, not a front and rear.........as I mentioned above...............
 
Freezerman said:
Just rechecked clocking on both sides. With the bump stops out, shocks disconnected and tbar adjusters backed all the way out, both sides hang very close to same. It sounds like I might be having to save up for new torsion bars?
Click to expand...

I'll ask you one more time. Did you switch the T bars left to right?
 
Sorry I missed your question. I just rechecked again. R is on passenger side.
 
The T-bar has a line and part number on the frame end, it should be horizontal. This just makes it easier to figure out the clocking. Mopar does even-odd for symmetrical parts, odd on driver side. and yes, passenger side is right when you look at car from rear like Mopar intended (or when you are driving)
 
^^ Not sure your latest process fully checks T-bar clocking but it does check the rest being equal.

Freezerman said:
Now when trying to set ride height I have to crank the drivers side in most of the way and the pass side about 1/2 way where I would expect it.
Click to expand...
Not sure I understand this statement.....have you tried backing off of the driver's side and tighten up the passenger more and see what you get?

And did you keep track of left and right? I never knew if there is L and R but always kept them on the same side...and I just saw this.....maybe others can confirm.
http://www.moparts.org/Tech/Archive/susp/7.html
Edit to add: I see they already did!

How are the rear springs as far as being even? If you jack up the car under the exact center of the K-member, does it seem even side-to-side when viewed from the rear?
 
If I turn both adjusters in the same amount the drivers side is always a lot lower(obvious tilt). For example if both sides adjusters have 2" of travel I have to turn the the drivers side in at least an inch to even out. If I turn the pass side in more it starts to look like no engine in the car.
 
I'm starting to think you have a weak torsion bar. It could be some of the spring twist has relaxed out of it.
 
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