Rubber vs Polyurethane???

[TripleBlackGator]

I am thinking about ordering a front end rebuild kit and I'm undecided to go with a rubber or poly kit. I'm sure a new rubber kit would be a BIG improvement over my old stock units. I was thinking though of going with the poly kit but I am concerned about ride quality. Has anyone gone from rubber to poly and if so what do you think? I would like the handling aspect but not at the cost of a harsh ride. How harsh are they?

[Ghoste]

You are going to get all kinds of answers to this one.  I have poly on mine and I don't find it too harsh and it doesn't make any noise either.

[71ChallengeHer]

You are going to get all kinds of answers to this one.  I have poly on mine and I don't find it too harsh and it doesn't make any noise either.

unless your worried about judging at shows. I think you get knocked points in SME juding if you have poly.

[TripleBlackGator]

You are going to get all kinds of answers to this one.  I have poly on mine and I don't find it too harsh and it doesn't make any noise either.

unless your worried about judging at shows. I think you get knocked points in SME juding if you have poly.

No judging at all. I just don't want a harsh ride or noise. I see some poly kits impreganted with graphite to help lessen the chance of noise. By the way. Why would poly's be a NO NO for SME judging. It's more for "modified" excellence than originality. That was my understanding. Here is a link to Totally Autos web page.

http://www.totallyautoinc.com/smejudging.html

[Ghoste]

Go with a mix.  Put poly on bushings that are being loaded in one direction only such lower control arm strut rod bushings.  Ones that receive a rotational load, like the control arms, use rubber.  That way you get the hardness of poly in the areas that benefit the most from it and rubber in the areas where nois and harshness would be most felt.  New rubber is going to perform as well as the poly for the most part anyway and I think it costs less.

[Charger-Bodie]

  and get the poly graphite ones they squeek alot less!!

[scottmiller]

I am rebuilding my suspension too.  Last time it was done was 15 years ago and I used rubber.

On the lower CA's I am thinking of going with the NYLON bushings offered by Firm Feel. My guess is they will be quieter than Poly because they won't "bind" the way POLY bushings do.  The uppers will be POLY on some new tubular upper CA's.

Anyone here ever use Nylon on the lower CA's?

Scott

[Ghoste]

I've never even heard of them.  Is it a new offering?

[TripleBlackGator]

and get the poly graphite ones they squeek alot less!!

Not what I hear. Explain.

[Charger-Bodie]

the poly graphite ones are impregnated with graphite to lube them as they work ive had good luck with them.

[chargercraig]

POLY. I coated mine with a small amount of grease to prevent squeeking, I'm very happy .

[Ghoste]

Me too, they may also be the poly-graphite ones to boot.  It's been long enough that I can't remember exactly but I do recall the little coating of grease.  I know they don't squeak and that's what matters.

[TUFCAT]

Rubber. Just like the factory used.

[scottmiller]

I am getting the greasable LCA Pins from here:

http://www.firmfeel.com/lcapins_b.htm

They offer Nylon or Urethane LCA bushings.

-Scott

[Just 6T9 CHGR]

the poly graphite ones are impregnated with graphite to lube them as they work ive had good luck with them.

I used this set up on my front suspension as well from Performance Suspension Components about 8 years ago with no noised or problems.  I did use the stock rubber in the rear though & I had to get rid of my KYB shocks because the ride was too harsh for these NYC streets

[Mike DC]

   
The debate about poly or rubber will never end.  I won't tear into which is better, but here's my two cents on making the decisions.

-----------------------------------------------------------------------------------

General things:

--  Are you considering switching to poly mostly because your old suspension is totally worn out and you want better road-feel?  Well, like you said in your original post, I agree you're not really comparing apples to apples right now.  Just a fresh stock rubber rebuild will already feel TONS better than the 35-to-40-year-old setup you're replacing.

--  The steering box (and sometimes even the rubber "rag joint" on the shaft) makes as much difference in road feel as anything.  All the poly on earth won't make up for unresolved problems in the steering assembly itself.

--  When evaluating whether some brand of poly bushing will squeak, keep in mind that the lube can squeeze out over time/miles.  So when someone swears by their brand of poly bushings, make sure they've at least had them in the car long enough to have changed the oil a few rounds.


Specific things:

--  Lower control arm bushings take more stress than most other things.  If there was one area where I'd be most inclined NOT to put poly into the car, it's this one. 
Check everything (including all around the K-frame mounting-hole areas) for metal fatigue/cracks when you have things apart.  For that matter, there are numerous spots to gusset on the front suspension metal that can prevent problems later on.  It's good to do this stuff if you're just building a decent driver and you don't care so much about a few extra welds in the wrong places.

--  Upper control arms might be a particularly GOOD spot for poly bushings.  (Although it's definitely a squeak-risk because they're a rotating pivot point.)  But the UCA's have a lot of influence on caster & camber.  And they don't carry the car's weight & take impacts the way the lower control arms do, so I wouldn't be as worried about them sending stress into the chassis like poly lower arm bushings.

--  In the back end of the car, it's a popular trick to put a rubber bushing in the front leaf-spring eye, and put poly bushings in the rear shackle.  It's a slick compromise.  The front bushing takes more impact, while the rear shackle bushings (particularly the upper set of bushings at the subframe rail) disproportionately influence lateral movements.


 

[HITMAN 149]

hey triple black....
your gonna get a million different debates & opinions...this topic has a ton of threads about it. toooo each his own specific needs & beliefs!!
just flip a coin...heads it's poly....tails it's rubber!!! LOL

i went with a brand new poly/graphite front end kit from performance suspensions, front & rear sway bars...KYB's all around.
STILLLLLLLL at the garage..sighhhhhh waiting...waiting...waiting!!! LOL but i'm sure it'll be worth the wait for all the work to be done!!!!

[resq302]

Well let me start off by saying I have used both.  I did a complete poly kit on my 85 Jeep CJ 7 and used the supplied lube for it.  After a month, the damn thing squeaked like a rusty door hinge.  They were also supposed to have graphite in it to help prevent the squeaking.  On my charger when I rebuilt the front end, I used rubber and it feels great.  I have also heard horror stories that people using poly bushings on the lower control arms have cracked the area on the k-frame where the pivot goes in.

To me, rubber would absorb more of the shock than what the polys would.  Also, if it was good enough for the factory, it is good enough for me.  The only place I have poly on my charger is the sway bar bushings where it mounts to the k-frame as they do not make rubber bushings for it.

[Charger-Bodie]

Well let me start off by saying I have used both.  I did a complete poly kit on my 85 Jeep CJ 7 and used the supplied lube for it.  After a month, the damn thing squeaked like a rusty door hinge.  They were also supposed to have graphite in it to help prevent the squeaking.  On my charger when I rebuilt the front end, I used rubber and it feels great.  I have also heard horror stories that people using poly bushings on the lower control arms have cracked the area on the k-frame where the pivot goes in.

To me, rubber would absorb more of the shock than what the polys would.  Also, if it was good enough for the factory, it is good enough for me.  The only place I have poly on my charger is the sway bar bushings where it mounts to the k-frame as they do not make rubber bushings for it.

i totally agree with you on the lower control arm bushings i always use rubber there but as for the rest its poly graphit all the way for me as my cars get driven ALOT!! i put on about 800 miles already this year !

[Sweet T]

I ordered a rubber set hopefully soon to be put in the car.  I am happy with the way the car drives with it's cracked and worn out 38 year old bushing so I think I'll like the new rubber.  What are you planning on doing with the car drifting against a CIVIC, road racing a Ferarri, or just cruising and kicking ass light to light?

[AKcharger]

Put polys in my wife's '72...squeeks like crazy!