Frankie the Fink

The 63 trailing arms are out with the help of a good forum pal (with an air-conditioned garage and all the tools for the job). The poly bushings shattered into nothingness, swiftly and catastrophically; unlike old rubber that will gradually "give it up" over a period of time....one side blew out on the trailing arm bushings.. which stressed the other side until it crumbled. The inner/outer wheel bearings and seals were actually OK. The metal core of the bushing arrangement was all that was left in either trailing arm

To wit, this entire job could have been avoided if a previous owner handn't used poly for the bushings. At any rate, the arms will be rebuilt with Timken bearings (still available apparently), new seals - dialed in and new front RUBBER bushings. The shim packs were intact so hopefully alignment will go easily..

Another downside to the poly is that the cumbly bits filled up the rear vertical drain area just outside the T/A cavity and prevented water draining. It was 20 minutes poking the junk out of the weep hole, vacuuming and blowing out with shop air to clear it out. See the bottom of the last picture.

The poly was a mistake and nothing but trouble....didn't even hold up on a lightly-driven, base motor car...

The greenish cast on the interior of the T/A cavity is the Eastwood Internal Chassis Treatment -- gives you a good idea of how it coats, encapsulates rust and protects the frame inside...

66RBS

The car I just bought is full of poly. Approx 10K miles on rebuild. The only damage so far is the bushings in the Vette Brake adjustable strut rods. The TA bushings look good and all shims intact. TA bushings are on my watch list


Randy

phil2302

Replaced all the original dried cracked original bushings in our 66 sometime in the early 90s with nice black rubber replacements and they are still in great condition.

Tampa Jerry

I am also in "recovery" with respects to poly. I had to keep the poly strut rod bushings as rubber will not fit the VB&P rods. You can still get them at Van Steel. Not a big deal to switch out every few years. Jerry

Robert61

I used poly when I restored my Pontiac. As I pulled the last bushing in place that feeling started creeping in that I should have used Moog. I called Summit to see if I was going to need one or two Moog kits. The guy says for just a few dollars more you can get poly urethane. I said I just finished replacing them and I'm going to swap them all out for rubber. The salesman then said well they've been in my car for 14 years without issue. I called a guy in the area that builds street rods professionally and asked his opinion. He stated that one car that stays in his show room and is never driven had poly and they started crumbling and falling out. I discussed it with my painter and he has had them in his 68 Chevelle over 20 years now. So I left them in. So far 4 years 10,000 miles on them no squeaks and no crumbling that I am aware of.

Frankie the Fink

Critter1

Yup, it's the TWIST that the rear control arm and strut rod are subject to, by design, when traveling through their range of motion. Not just the up and down motion.

It's still amazing that several well known Corvette suspension experts still sell and/or recommend these poly bushings for the rear control arm and strut rod.

The 1st picture in your 1st post clearly shows that, with the car jacked up and suspension hanging, the control arm is correctly rotated to change camber.

Mr D.

I think poly bushings in general are snake oil products.

vettepoor

SpedRacr93

I agree with this.

All these guys do is mix it up, pour it into a mold and then bake it.

The majority of the molds are oversized, so you end up having to trim them to install them. They bind and wear poorly or crumble.

I've never checked into any of the manufacturers, but having toured many factories over the years in Asia, I can believe that the compounds used have R E A L L Y W I D E degrees of tolerance and are sometimes overly full of fillers or just plain junk. The cheaper they can make a product, the more money they make...

I've had several bushings from a certain Vette Brakes and Suspension supplier who recently folded their tent, that crumbled within days of installation.

They probably don't even reference a specification on the poly when they buy it from overseas. If they do, I would be shocked if they ever checked that what they received was actually to that spec.

firstgear

The previous owner, previous owner installed those. That puts them in there more than 10 years.....

Frankie the Fink

It was a prior owner before you Herb.....the trailing arms were powder coated and the bearings nicely packed with modern grease which hadn't congealed. Ten years or ten months no matter IMO - I don't like catastrophic parts failures.

I had driven 3 miles to the local NAPA store -- fat, dumb and happy - no problems. Two miles from home on the return trip the rear end of the split window suddenly just "came loose" and started "twerking" like a drunk girl at a booty call. Every time I got on or off the gas... I literally thought I'd torn the rear end out of the car somehow (which is partially true I guess)...

No worries - I'm using the opportunity to install a fresh snubber bushing, zerk-less U-joints on the half-shafts and new strut rod bushings -- along with new rear leaf spring rubber. The sombreros -- well; we'll see...

Frankie the Fink

Not good - that's a "single shear" bushing that has both lateral and compression stress too. I wouldn't use 'em AT ALL.

wmf62

"twerking" like a drunk girl at a booty call

i'm not familiar with that; please describe (pictures would be better)

Bill

Frankie the Fink

Pretty much like:


It was exhilarating and scary at the same time....
Hmmm.....maybe that poly stuff isn't so bad

My apologies to the moderators ahead of time but I WAS asked!

GTOguy

Thanks for the post, Frank. And it pretty much sums up why I never used poly bushings after one mis-guided sway bar bushing episode on one of my GTO's in the '80's. It's Moog Rubber for me, and hopefully they'll keep making it so it holds up, unlike off-shore rubber. I like the frame coating inside the rails of your car.....makes me feel like I'm looking into the superstructure of a P-51 or P-38...and that's not a bad thing!!

BADBIRDCAGE

MOOG doesn’t mean quality now like it used to. 15 years ago searched out for MOOG ball joints for my 63. One was a spot on USA manufactured replacement product. The other was a reboxed product from Brazil. Same part number, same packaging, different in physical appearance (flat v top hat).

dcamick

What were we talking about?????

MOXIE62

What I would do is probably what you will be doing is remove the body bolt, wire drill brush the area down to good clean metal and paint.

biggd

I agree. Although just like all aftermarket auto parts, there are quality parts and cheap crap.