Poly graphite or Rubber UCA / LCA bushings??

[MikeyM]

Hi all,

You may have read in a recent thread that I'm starting my suspension rebuild, currently tearing it all down to see what's needed. I have a couple questions. I like (and have installed in the past on various cars) rubber bushings for the ride quality. But I like poly-x for the longevity but I don't like the squeak. I've read here that poly graphite bushings do NOT squeak, if installed correctly, and if so, that is very appealing since the last much longer, correct? How is the ride compared to rubber? Initially I was going to go all rubber for the UCA / LCA bushings and poly for the strut rods and sway bars but after reading a few that a few folks always use poly graphite for various reasons, I was hoping to get some feedback on the ride quality compared to rubber.

Thing 2 - after knocking loose the tie rod ends, I found they are pretty tight with no slop at all. Seemingly, the same with the ball joints. I'll know more once I get the knuckle off. The rubber boots are toast on everything but since the car has 64k original miles, I'm on the fence on whether I should replace them or not. If I find the BJs and TREs are tight, I know I could simply swap boots and call it good. I DO want to to it "right" but anyone have any thoughts? What kind of service life do the OEM units typically have? They do have a lot of grease in them, just all the boots are wasted.

Thanks,
Mikey

 

[Kern Dog]

The two basic materials most commonly used are Rubber and Urethane.
The suppliers will call the non rubber materials by a variety of names, Polygraphite being one of the many. They are all some sort of plastic that is stiffer and deforms less than rubber.
There are parts of the suspension that the stiffer components are a great benefit, but other places where it transmits more harshness than you may want in a street car where the roads are not perfect.
Me? For the front end, I use Urethane in the strut rods, the sway bar, the bump stops and that is it. Every other point is rubber. Some people use the urethane in the control arms. THAT will result in more harshness than you may like.
I did use urethane in the leaf spring shackles but the front bushing in the leaf springs is still rubber.

 

[MikeyM]

Thanks KD, same page of thought.

Mikey

 

[dvw]

OE parts in good shape can definately be used. My 64 stiil uses the original ball joints, pitman arm and inner tie rods. The outers were in good shape but were swapped for heims to correct bump steer. It's has urethane elowers and strut rod bushings. Can't comment on ride quality, but they haven't failed. Even after thousands of wheel stands.
Dou

 

[Frank Mopar]

I had a BMW I put poly bushings in. Two weeks later they were replaced with stock rubber.

 

[AR67GTX]

I don’t believe poly is durable in something like the LCA shaft bushing. The bushing is exposed in that connection to some twisting as the suspension cycles up and due to the strut rods. That tears up poly but rubber deals with it fine. Poly works fine in something like the upper control arm bushings that cycles up and down with no twisting. But I like quality OEM rubber bushings myself except for sway bar bushings and end links.

 

[WileE]

What they say, and I'd prefer re-using the original GOOD quality parts if not worn.

 

[Tony Tee]

I work for a company that molds urethane. And i prefer real rubber that doesn't disintegrate or crack or turn into goo. I'd only use urethane on suspension parts like sway bar end links and bump stops that do not twist. Just my opinion.
Its your car. Build it and and have fun.