OldCarBum

During my research I was told by several manufactures, that if you buy cheap rubber, you get what you pay for. Poly is better than the cheap rubber. If you want the best all around with the best quality parts go Moog rubber suspension kits and parts.

Tampa Jerry

I installed poly on my trailing arms on my 66. They lasted about two years and turned hard and fell out. My friends 67 did the same thing. Both of the cars have side pipes. I was told by one of the major suspension vendors here on the forum that the exhaust gas creates havoc on the poly bushings in the trailing arms. I had the old arms out in about an hour and replaced them with rubber. It was easy with a lift with only 200 miles on a frame off resto. I will stick with rubber. Jerry

0Willcox Corvette

The only rubber suspension bushings (and ball joints, tie rod ends etc.) we sell front or rear are made by Federal Mogul (which owns Moog) While it comes to us in a white box, it's still FM joints, tie rods and bushings.

Willcox

resdoggie

Pros and cons - have a read.

http://www.suspension.com/blog/rubbe...sion-bushings/

If poly is crumbling, I'd question the quality of the poly and how it was installed. Lots of yahoo's out there that throw the instructions away and proceed with the install. Then complain about a sh1tty product. Yes, it happens, all the time.

jb78L-82

Bingo....spot on link!...there is no such thing as only rubber or only poly.....each has its benefits and weaknesses....

I guess it comes down to, do you want your C3 to be a grand tourer or a sportscar....????

DUB

Rubber trailing arm bushings is what I use. I have used poly before...but no longer.

DUB

cagotzmann

I have not used energy suspension parts other than poly / engine mounts, which I found to be poor quality after 2 years.

As for suspension parts, I have poly everywhere since 2012, many track days and not 1 failure or squeak from any bushing.

But I am using this brand. Prothane.

http://www.prothanesuspensionparts.com/72012

Also read in the above link

"Prothane's Super Grease to lubricate the bushings during installation"

Metalhead140

Yeh, I wonder about causes for the poly crumbling too. I do compete in my car, but I do a lot of street miles also. I think rubber would be more than fine for a cruiser. If my poly fails, I'll go further down the rabbit hole and fit arms with spherical bearings. May well do that sooner or later anyway.

resdoggie

The biggest difference in poly and rubber is that poly MUST be lubricated so it doesn't bind. Rubber can move about in all planes of movement in tension/compression. Poly is not that forgiving nor is it meant to be. Hence, it requires lubrication so it slides on the bearings eliminating some of the planes of movement or it will fail such as crumbling.

jb78L-82

My poly upper and lower front control arm bushings are PROTHANE as well with zero issues now for about 10-12 years since installation. I do not intend to use poly for the TA bushings but I really don't understand when folks say that they would never use poly anywhere on a C3? IMHO I really do feel based on my personal experience with my C3 that poly front control arm bushings, poly swaybar mounting and endlinks, rear composite spring end cushings, poly power steering ram bushing, etc are FAR Superior to the rubber counterparts and have very few detrimental side effects.

The poly bushings that I did have for over 25 years in the rear strut OEM rods did squeak BUT when I replaced them with the competition adjustable struts with heim joints in 2006-2007, unbelievably, the poly bushings looked brand new...I still have them in my garage in storage....

PainfullySlow

I guess it all boils down to quality of components and installation techniques.

Personally I will be going poly for my suspension and rubber for chassis mounts in an effort to help dampen some of the excess vibrations.

There are those here who will swear to you that poly is terrible, that it can explode or catch fire, and that poly is responsible for global warming and trumps election. The simple fact is that QUALITY parts get QUALITY results...rubber or poly, it doesn't matter. For what it is worth, I will also be using Prothane products.

Poly requires a better installation technique which many are simply unaccustomed or unprepared for. That picture posted earlier in this thread of the bushing torn apart is a direct result of lack of lubrication...an INSTALLATION failure. As someone above mentioned poly has a tendency to 'stick' if not properly lubricated and by looking at that I can tell you that it was dry, bound up, and tore itself to pieces when it was asked to move.

So, rather than vilify one or the other, how about we focus on which material is right for you?

Daily driver, cruiser only, keeping it original, don't want to deal with periodic maintenance, or just plain old school: rubber is the way to go

Track, more spirited driving, better handling but harsher ride: Poly with the understanding that it does require maintenance.

Either way, both materials have their place on our beloved C3's. Just figure out which is the right one for what you want to do and go with there...but either way, just buy quality products.

Dennis Tapp

This is a great reading for me at this time. The question I have now in trying to decide the way I am going to go. Does the poly make the frame twist more and is that good or bad? I am building a cruiser but all of this reading the last month is making me want to look for a real beater (after I am done on this one) and go all out with a track car.

jb78L-82

Excellent explanation and well said....

PainfullySlow

Logic will tell you that excessive frame flex is bad. It also stands to reason that a firmer interface between parts (poly bushings) will transmit more energy and so yes, the frame will flex more. Whether or not that equates to excessive flex is the question, and I am afraid that I cannot answer for you.

Physics I know...these cars, not so much yet :-p

I am a real sticker for handling but if I were going to build a cruiser (and I wasn't this way) I would probably use rubber. Plush and easy driving.

DUB

Way back when Vette Brake and Products started selling the poly bushings I often heard from the 'old timers' who were set in their ways that using poly will make the car so harsh of a ride.... you will feel it in the seat of your pants due to it is not absorbing as well as rubber will.

Their is some truth to that...but I HONESTLY have never had anyone...nor myself feel a drastic increase in road irregularities when the poly was installed. What was felt was a crisper feel in the handling. But also remember that installing these bushing alone is doing no good if you also have other suspension parts worn out.

I can say this...and it is only my observations of doing numerous poly urethane bushing install over the decades I have been doing this. What I have found in many cases is that when the original control arm bushings are removed. The teeth that are on the ends of the sleeves that bite into the backside of the cupped washer and ALSO into the cross shaft. The cross shaft can actually show some significant wear due to these teeth. So when a person slides the sleeve onto the shaft and carefully looks at it. They have to ask themselves if the material on the cross shaft has enough integrity to now be able to correctly back up this sleeve....or does it seem like it could become a problem later on down the road.

Knowing that VB and P's poly bushing have sleeves that often times requires them to be cut to a specific length....consider that also. Because there were times when I was right a the limit of the sleeve not being able to work due to the wear on the cross shaft. And in some cases I needed to get a new cross shaft with no wear on it.

I have installed a few of the Prothane bushings and they never seemed to have a problem...but with their design being different than VB and P's...I often times wondered IF they were good to go or not due to the sleeve in the bushing. And the reason I wondered about it is that I know I am not compressing the urethane...and IF the sleeve is not long enough to actually make contact with the washer and the land on the cross shaft. If there was going to be a problem in the bolt backing itself out....when they are used on cross shafts with obvious
visual wear like previously mentioned.

One trick...is that I do use Prothane's lube that is sticky as all get out and stays put. And I also all some silver anti-seize compound to the lube so I can actually see it being applied.

I prefer not to install any poly urethane bushings...I prefer to install the Global West Del-a-Lum control arm bushings.

I have no problem if a customer wants poly urethane for a sway bar...because if it fails...it takes no time to replace. And as for rear spring bolts cushions..I prefer rubber due to I have seen many of the urethane ones shatter and break apart.

DUB

The13Bats

I fully understand why the factory used rubber ( good ) rubber and why some guys want a bit more sports car feel from their corvette and upgrade from rubber, for others rubber is good enough.

Like many of you i have 35 plus years putzing with these cars and others and have seen both rubber and poly wear out, fail whatever you want to lable it,
and as years have passed i see more crap rubber than crap poly, but thats just me,

Its the manufacturers fault, vendors are at their mercy but if they sell crap need to stand behind it,

i find VBP bushing worthless yet most people who actually run them love them and have no issues so there is a great example showing a persons negative opinion and biases are not always across the board facts,

my big bias is against crap parts in general,
Saying just because its this or that it is automatically crap is hogwash,

If a person uses good rubber or good poly either will and does work anyplace on a c3 too many people using either successfully to argue that fact.

Want rubber run rubber want poly go poly,
Just be 100% sure you get good stuff not crap....

jb78L-82

Dub, your comment about the LACK of harshness is exactly my observation and reality after 10 years of the Prothane poly front upper and lower control arm bushings on my 78....I noticed almost zero ride degradation using poly in the control arms and do constantly refute the comments about the harshness, firmness, frame flex etc that is often shared by some. I simply have not experienced this with poly bushings.

On a side note, my competition rear adjustable struts with heim joints are often described by some and even the vendor as "for off road use only"...completely NOT my experience with heim joints...zero difference in ride versus my OEM struts with poly bushings...ZERO!

The13Bats

I have that, been told on here it will break from street use,
Waiting for someone will pop up and say they did break one from street use to confirm that opinion....

resdoggie

Just because one or two guys have a part fail doesn't mean the other 1000 guys will have a failure also. But then a myth spreads over cyberspace that all said parts are sh1tty. It can happen with a bad batch of parts or a poor design to begin with but then there would be many, many failures to justify it is a sh1tty part. Poly is nowhere near the sh1tty part status except in here.

Big2Bird

Well, speaking of that, this summer I took the 81 on a 6200 mile Route 66 road trip.
The car was redone with poly 12 years ago sourced from VBandP . Where they get them I do not know.
BEFORE I left, I examined them all.
I changed the front sway bar link bushings and the P/S ram bushings, because they looked tired.
DURING the trip, we hit a bad section of 66 rarely used up north east of Santa Fe. An old railroad rail type cattle guard had sunk about 6", and we hit it HARD.So HARD, it snapped the mirror off the windshield and cracked the windshield.
After we got back and rested, I reinspected the suspension.
The rear spring cocked in the pocket a few degrees, the rear sway links had 2 bushings GONE, and one spring hanger bolt cushion was cracked.
I have since replaced those items, along with the rear spring cushion.
SO, my take on these items.
Poly will tighten up the car, absolutely.
Poly WILL crack/wear out faster than rubber due to it's lack of compliance.
Poly works great on a arms, pillow blocks, and have very little "stick-tion." in a purely rotational bearing type application.
The next time I change the a arm bushings, I will
1)Go rubber. The arc type movement binds with poly.
)Johnny joints. These tighten up the joint like poly, but permit arc type movement. I believe My Bad and TT came up with this years ago.
The rest, they get new poly as needed. Worth the effort and cost, IMHO.
BTW, the rear links are Coleman racing aluminum units with HEIM joints. They didn't wink at the impact. Tight and weigh zippo.