Poly Bushings issues

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1970Duster

1970Duster

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Okay, okay, we all know that you're supposed to use rubber bushing in the lower control arm because the poly bushing will make noise. However, what actually causes that problem?
Here is a part for the rubber bushing
http://www.americanmuscle.biz/34572_lower_control_arm_pivot_RUBBER_p/34572.htm

And this is the part for the poly bushing
http://www.americanmuscle.biz/34571_lower_control_arm_pivot_poly_p/34571.htm

Notice that they are different. Could the reason poly bushing in the lower control arm is not used because people are use the wrong pivot?
Anybody using this poly designed pivot with a poly bushing and it still make noise and which type of poly bushing are you using?
 
That makes a whole lotta sense, especially since the rubber pivot has that ball instead of a cylindrical stop. The ball probably fits into a socket in the rubber bushing, but when you put a poly bushing on it, there is no socket, and all the force tries to wedge the poly bushing over the ball. that'd make a hell of a racket, and probably shorten the life of the poly bushing considerably too.
 
Hmmm, don't know.

If I were going to use poly LCA bushing, and I am, I'd use the grease-able LCA pin from Firm Feel.

All the benefits of Poly with a little squirt of grease to keep 'em quiet.


Regards,

Joe Dokes
 
Looks like I'm ordering that pivot for the poly bushings.
 
Joe Dokes said:
Hmmm, don't know.

If I were going to use poly LCA bushing, and I am, I'd use the grease-able LCA pin from Firm Feel.

All the benefits of Poly with a little squirt of grease to keep 'em quiet.


Regards,

Joe Dokes
Click to expand...

My thoughts exactly.
Aftermarket offers about anything if you search long enough.
Oh and by the way, I dont recall seeing a pin with that raduised ball like shoulder before. Maybe that was designed for their rubber bushing that doesn't have a inner sleeve ?
 
I've got poly upper and lower bushings and only the uppers made some noise after I started using the car.
Mostly during the winter.
But some repeated squirts of some sticky (stinky) lubricant on the uppers made the noises dissapear.
 
The complaint with poly lca bushing isn't just noise. Noise is common on all poly bushings. They do make a special grease for greasing poly suspension bushings.

The complaint with poly lca's is the fact that there is no friction/tension from the bushing acting on the lca to keep it from moving forward or backwards on the bushing. Some people have gotten clever and designed lca pins that have a positive stop on them to prevent the arm from walking, but I don't recall the specifics. With normal pins and poly bushing the torsion bar is all that locates the lca and keep it from sliding off the back of the pin.
 
I use the Firmfeel greasable pins and their adjustable struts to seat the bushing correctly and keep it from walking. So far (about 4 years now) the setup has worked perfectly.
If you want to save some coin use marine grease, the blue snotty stuff thats used on lower legs on outboards and outdrives. It's widely available and costs TONS less than what you'd pay from a poly bushing vendor for the exact same stuff.
 
What year use the pivot with the ball.My dart is a 67 and when I put poly on mine the pivot shaft didn't have any ball like that, it was like picture #2.I don't have any squeaking problems with mine........yet
 
Ditto above on the factory pivot bolt not having a spherical stop. I just removed them from my 64 Valiant last night. They look more like AM's 34751 "poly" bolt, but with a step down for the inner metal shell.

Since the innards popped out easy with my shop press and the outer bushing shell was left wedged in the LCA, I was thinking how a poly bushing would be nice to just slide into the shell. Like others, my concern is that a poly bushing doesn't support the LCA axially, so the torsion bar could slide back if its little rear clip were to fail. Since nothing to grab hold of to press out the outer shell, I tediously folded it in with a cold chisel then peeled it out. Tonight I get to do that on the other LCA. I see that AM sells a tool to grab the outer shell, but $42 and not sure how well it works.
 
BillGrissom said:
Ditto above on the factory pivot bolt not having a spherical stop. I just removed them from my 64 Valiant last night. They look more like AM's 34751 "poly" bolt, but with a step down for the inner metal shell.

Since the innards popped out easy with my shop press and the outer bushing shell was left wedged in the LCA, I was thinking how a poly bushing would be nice to just slide into the shell. Like others, my concern is that a poly bushing doesn't support the LCA axially, so the torsion bar could slide back if its little rear clip were to fail. Since nothing to grab hold of to press out the outer shell, I tediously folded it in with a cold chisel then peeled it out. Tonight I get to do that on the other LCA. I see that AM sells a tool to grab the outer shell, but $42 and not sure how well it works.
Click to expand...

I can tell you right now that using the tools they sell makes the entire job SO MUCH EASIER!! It took me longer to find the correct size socket and wench (7/8 just to let you know) then to get the uca bushing and the lca bushing.
 
I just finished doing to poly front end rebuild. And while I was putting it
back together, I started to have problems with the LCA bushing.

I used their grease to lube all the bushings, and I did it all the correct way.
So why does the LCA keep moving towards the rear of the car after I tighten
everything up?

Well in my case, it was the strut rod bushing. There are two halves to the
Strut rod bushing. The one on the back side is too thick. I could not even
get the nut on far enough to see the roll pin hole.

Remember that the strut rod bolts to the LCA and that is a solid connection
that does not have any give to it.
So if the POLY SRB is too thick, it will move the LCA back AND out of where
it is suppose to be.

This is why you will hear a popping noise in the travel of the front
suspension if you don't correct it, the torsion bar is in a bind because it
is not lined up with the LCA and the LCA is not all the way on the bushing.
And of corse the car will handle like crap. Also it is why the rubber
LCA bushing don't last.

Sooooo.....I ended up shaving a good amount from the rear strut rod
bushing. And because I had to use the sleeve the kit provided I needed
a different front washer that would go over the sleeve to compress the
bushings.

Now everything lines up, the car goes straight and is quiet.
I know this sounds like a hack job, it's what worked for my car.
 
never have had any issues with running PST's from end stuff... just press out the pin, take the old rubber bushing out while leaving the old sleeve, then grease and install new Poly LCA bushing...
 
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