OEM Upper Control Arm Bushing and Positive Caster

[DLJ]

I am having to re-do the upper control arms bushings on my Dodge Dart due to very premature failure of the brand new front bushings (60 miles or so), the front bushings became loose and the UCA running back and forth on the front bushings.

I have oredered new bushings and I know most will say I need new UCAs but I`d like some input on the bushings I have just got in the mail, they look weird to me, pictures below.

The online shop where I bought them said they were going to send either moog or federal mogul made in USA, but that is what I got.

These weird looking bushings are off specs, the external diameter in the middle is about 0.5 mm (0,02") larger than the stock bushing I had bought before and the end where it is supposed to touch the UCA is curved resulting in a larger diameter, so the bushing will not be pressed all the way in the UCA bore.

I believe my upper control arms bores where the bushings are installed are a bit worn out but the new bushings were pressed about 2 months ago using a manual press in a way I could fell how much force it was required to push them in place and I did not notice much difference when pressing the front and rear bushings in the UCA, they both required some good amount of effort to be pressed in so I believed they would be ok.

These UCAs have the metal collar/sleeve pressed on the rear bushing, which works very well to lock the bushing in place. I say that because I put back the collars on the rear bushings and they did not move, but this is what happened to the front bushings:

Upper control arm bushing extra part?



I have already ordered new real moog UCA bushings and will probably try to return the weird ones above.

I also found a standard size metal pipe to fabricate the collars/sleeves for the front bushings too. They will fit tight.

My other question would be:
Using the OEM Upper Control Arm and centered rubber bushings, trying to align to get the + Caster, puts the UCA in a twisted positition in the mounts, the front of the UCA will be all out and the rear all in to start with.
I am trying to get about 0.6 to 0.8 degree Negative Camber and at least 1,5 Positive Caster, which I was able to before the front bushings on the UCA got loose.
IMO, the twisted UCA position for + Caster makes the bushings not paralell to the frame and that may cause some more stress to the bushings.
I`d be interested in knowing what alignment numbers we can expect to get using these OEM parts and if the max Positive Caster position on the UCA can cause premature failure on the OEM bushings. Thanks for any comments.

 

[1969383S]

Those look very poor! I would not use them!

Do not forget about the eccentric bolts and thread depth. Maybe why your new ones failed in short order to begin with.

 

[Frank Mopar]

Something is amiss if your control arm is moving. Whats happening at the rear bushing? Thats the one that keeps the arm from moving backwards not the press fit.

As long as you have it apart you should use offset bushing to get more caster.

 

[DLJ]

Those look very poor! I would not use them!

Do not forget about the eccentric bolts and thread depth. Maybe why your new ones failed in short order to begin with.

Thanks. I am waiting for the moog bushings to compare them and figure it out.

 

[DLJ]

Something is amiss if your control arm is moving. Whats happening at the rear bushing? Thats the one that keeps the arm from moving backwards not the press fit.

As long as you have it apart you should use offset bushing to get more caster.

After doing some measurements, I believe the UCA ends are off about 0.16", the measurement from the front and rear bushings is short and I did not notice that when I assembled them, because in the process of assembling them on the mounts I had to pull them open a bit in order to make them fit there.



Still, that alone should not cause the bushing to become loose,
The rear bushings on both UCAs have that metal Ring or collar pressed on them and that really locks the bushing in place.
Once the UCAs bores where the bushings are pressed in might have some wearing, I think if I had used the collars in the front bushings that would not have happened.

Again, I believe that setting the UCAs for maximum + Caster squeezes the bushings in a twisted position and that may cause premature failure.



The offset bushings would be a way to go but I heard they are not as durable as the conventional bushings.

 

[Frank Mopar]

The bushing don’t need metal rings on them. The collar on the bushings on each end keeps the arm from moving back and forth.

You need to set the caster and camber then pinch them in place with the cam bolts and the car at ride height.

 

[694spd]

Here are a few reference pictures showing the Moog K7103 Offset Bushing compared to the Moog K408 standard bushing.
I do not know why they manufacture the offset bushings shorter which requires you to add the plated spacer washers to make up the difference?

 

[Frank Mopar]

Here are a few reference pictures showing the Moog K7103 Offset Bushing compared to the Moog K408 standard bushing.
I do not know why they manufacture the offset bushings shorter which requires you to add the plated spacer washers to make up the difference?

View attachment 1715402317

View attachment 1715402318

View attachment 1715402320

i don't know why either but I just installed a set in my 67 and they fit perfectly. Only thing is the directions say to point the arrow toward the ball joint. Thats incorrect. One needs to point away to get most caster

 

[694spd]

i don't know why either but I just installed a set in my 67 and they fit perfectly. Only thing is the directions say to point the arrow toward the ball joint. Thats incorrect. One needs to point away to get most caster

That is right. To get max positive caster you need to install then as shown in the illustration below.

 

[DLJ]

Finished replacing the loose bushings on both UCAs, used new moog rubber and added the collar/retainer, I managed to make out from a standard size pipe I found. They fit very tight, I think the metal pipe I found is the exact same size as the original metal collars I have on the rear UCA bushings.
For now, all holding in place.
I believe that setting the UCAs for maximum positive caster puts the UCA and bushings in a twisted position compared to the frame and cam bolts and that may cause premature failure.
The offset bushings would be great, but still, I'd not feel comfortable to set cam bolts for max + caster using those, just do not seem they will last long.
Curious what alignment others have on stock UCAs and bushings.
I am setting mine now for
Camber: - 0.7
Caster: + 1.5
All stock parts.

 

[Frank Mopar]

You can’t just put offset bushing in and get max caster. By the time you dial in the camber with offset bushings you end up at around +3 caster.

I still fail to see why you need a homemade retainer. The bushing design keeps them from moving back and forth.

 

[DLJ]

You can’t just put offset bushing in and get max caster. By the time you dial in the camber with offset bushings you end up at around +3 caster.

I still fail to see why you need a homemade retainer. The bushing design keeps them from moving back and forth.

Only the front bushings on the UCAs became loose, as I show in the video. The rear bushings were fine (they had the collars pressed on them).
I replaced only the front bushings adding the metal collar to lock them in place. Both UCAs had to be stretched a bit, distance between front and rear bushings was a bit short to fit right. On passenger side I could set caster + 2.5 with - 0.8 camber but on drivers max caster is + 1.5 when camber is - 0.7 so that is what I will set for both sides.

 

[jos51700]

Here are a few reference pictures showing the Moog K7103 Offset Bushing compared to the Moog K408 standard bushing.
I do not know why they manufacture the offset bushings shorter which requires you to add the plated spacer washers to make up the difference?

View attachment 1715402317

View attachment 1715402318

View attachment 1715402320

i don't know why either but I just installed a set in my 67 and they fit perfectly. Only thing is the directions say to point the arrow toward the ball joint. Thats incorrect. One needs to point away to get most caster

They did that because they used bushings from some other application, and are using the washer to make up the length difference. Yuck.

OP, consider a tack weld on the new bushings after installation. I did a zap to the control arm (Mig or Tig welding only, NO ARC WELDING). That way they're held in place in case the press fit on your arm is less than ideal. This is what the factory collars attempt to do, which I used and tacked them, too.

And do not press in the upper ball joint!

 

[Frank Mopar]

If the total length with bushings installed is incorrect then I would shim in the front and back.

Attempting to stop the movement any other way seems wrong. IMHO