Rear Sway Bar Bushing Options?
 

I noticed that I need to replace the leaf spring bushings due to dry rot. While removing the springs, I see the lower sway bar link bushings are toast. Looks like someone cut pieces of heater hose to use there. Are there any options other than polyurethane for replacements?

Orig. number was 3986486 for 7/8" I.D.

Wow!! The silence is deafening. No one has any ideas?

Ames had all the sway bar parts listed for my 74

This is what my car had when I bought it.

https://i.imgur.com/FULgXoql.jpg

The car is a 70 TA and should have had the heavier bar, but apparently, they didn't all get that. Anyway, as you can see, whoever restored the car couldn't find the right bushings. I have no idea what that was but it obviously didn't fit. I don't even think it really was a bushing. I looked all over to find the correct bushings and failed. I ended up buying an aftermarket bar that was .875 (7/8) that came with all the bushings. It was the Addco brand bar. Sacrilege, I know, but I did what I had to do.

NOS ones used to pop up once in a while on eBay, although the 7/8 ones seem really hard to find. The last two cars I had came to me with heater hose in place of the bushings. I just used the polyurethane ones (black) because they have the shoulders on them and won't slide out.

There's an old thread which might be helpful.

http://forums.maxperformanceinc.com/...d.php?t=814904

Ric,
I think your choices are urethane, heater hose or NOS. I would not recommend urethane for subframe or control arms, but I suspect you’ll never know the difference on a rear sway bar. Ames has them for 5/8, 3/4 and 7/8 bars.

People gotta start 3d printing that kind of part. TPU (thermoplastic poly urethane) filament is incredibly tough and most bushings are very simple designs. Not suitable for metal/rubber bonded type bushings though.

Thanks for the input guys. NOS seems unobtanium at any price, at least, so far.

I stumbled across a strong possibility a couple days ago and ordered the part. Should be here Tuesday or Wednesday. I'll keep it a secret for now, but will let everyone know what it fits, especially if it works. (Hint; NOS & rubber.)

Good read from 2018....https://forums.maxperformanceinc.com...bushing&page=2
Energy Suspension sells a BLACK Poly bushing in a "kit" for the Bar ( bottom of lower link) This bushing has lips on the edges which keep it in place. works better than an original once lubed. When WS-6 was introduced in second gen Birds the anti sway bar bushings in POLY was part of the package..
https://forums.maxperformanceinc.com...6&d=1712027608

Where all the WS-6 bushings POLY? I remember the link bushings being white plastic of some sort (POLY) but thought the frame mounts and rear bars were rubber.

Just the end links were poly, both ends up front, ( 4 parts) and lower in rear( 2 parts) . There's the 6 in the wide suspension handling option.

Dont believe I've ever read of original 2nd Gen WS6 bushings being referred to as of POLY construction.
Instead have read several times that the WS6 rear sway bar lower bushings were made of a harder durometer rubber. Do know these black swaybar bushings were identified by a different color of stripe on the flat section of the bushing. Have several pair that I put up decades ago, the least usage sets I picked up off the ground under two '80 Indy Pacecars that were being parted at huge local late model GM yard, that was in 1982.

The front swaybar link bushings went from being made of rubber in normal applications, to with the WS6 option, being made a of an off whitish color hard material that yellowed some with age. Those front link bushings had no give to them, more resembled the construction of a faucet seat washer. in late 83, maybe early '84, Herb Adams VSE had a sale on swaybars , & I removed my original front bar & rear WS6 bar & after swapping on the Herb pieces, kept all the original bushings.

Thought I'd give it a shot printing up a bushing in TPU 95A.

Turned out nice. This stuff is tough as nails. A bit harder than rubber, a bit softer than typical performance poly bushings.

This example is 3/4" ID, 1.125 OD, about 1.5" long. It does have a chamfer on the inside edge of the ends ... makes printing easier, would probably be possible to do away with that.

Can be made in any size/dia/color etc.

https://forums.maxperformanceinc.com...9&d=1712091588

Data. Have you tried to pull that apart and install on a rear bar? It's not brittle? May have a different project for you too.

Whatcha got in mind?

Yep, it will pull apart far enough to fit around a bar, not easy, but by no means hard ... right in line with what you would expect from a hard rubber part.

Not brittle at all, you could force it open/flat in a vise and then it would go back to it's original shape. TPU is what's used for shoe soles and heels and other very high wear parts. In engineering terms it's extremely "tough", deforms a LOT without taking a set, very high impact strength etc. It can be printed with varying levels of stiffness by changing the density with which it's printed .. from "squishy" like foam, to hard like a shoe heel.

In a sway-bar application it would be hard to say if it would remain fixed on the bar and clamp and flex internally (like a control arm bushing) or if it would remain fixed in the clamp and the bar would pivot inside (like hard poly bushings).

Parts that have been on my list to experiment with are:
Front sway bar bushings (since the 68 aftermarket examples don't fit right)
Radiator support bushings (would be close to the temp limits of the TPU)
Body support bushing
Hood bumpers and various other bumper all over the car.

It's pretty amazing stuff, you could make Pitbull chew toys with this.

As an example, the part I posted above took about 67 cents worth of filament, took about ten minutes to design, about three hours to print. (Bear in mind "print time" ... requires no attention from me, sometimes I even forget something is printing, kind of like throwing clothes in a washing machine)

I don't want to hijack this thread but parts like these are easily accessible to the Pontiac Community.

1. Someone takes good measurements of needed part

2. Someone like me can create the necessary CAD file based on the measurements or part in hand.

3. The necessary file(s) is given to the community.

4. Part can be made by a vast array of online services where you upload the CAD file, they make it, send the parts to you (usually reasonably priced ... say $10 each for the bushing example)

5. Or, a "Pontiac Friend" like myself can print the part(s) in limited numbers for most likely free.

Bushings are mostly very simple parts, easy to model, easy to print.

Promised you guys I'd let you know what I found on the rear bar center bushings.
One guess I made looks like it can work,...the other guess, not so much.
The 'not so much' is the 680-205 on the left. That's for a Triumph TR6 with a 3/4" front bar. Would need massaging to fit well.

The #3986486 is a NOS correct part for the TA 7/8" bar I stumbled on. SCORE!! That left me finding a #3851087 Chevy bushing which is VERY close to a correct original part. Only difference is the center diameter measures 13/16" instead if 7/8". I'm thinking that'll work just fine.
What is the 3851087 original application?? 1964 - 67 Corvair front bar link bushing! So I'll be driving around thanking a Corvair for getting me back on the road. (Next Summer)

Congrats on finding something.
These are among the few things I have yet to track down for the future restoration of my 4-speed T/A. (It has a 5/8" rear bar on it, though)

Looks like a radiator heater hose
 

Now I can see why people replaced this part with 3/4 heater hose. basically looks the same. My originals looked like worn heater hose.
Nice score