Just finished an environmental test on the polyurethane bushings on my Hellwig sway bar.
I went to move my rolling chassis and found that they had all disintegrated - just sitting there in the shop.
I think I'll get some rubber ones.
Just finished an environmental test on the polyurethane bushings on my Hellwig sway bar.
I went to move my rolling chassis and found that they had all disintegrated - just sitting there in the shop.
I think I'll get some rubber ones.
What was the shelf life on your car just curious realizing you don't know when they were built. The hellwig purchased for my car appear to be rubber not poly but I could be wrong just FYI.
Last edited by rockytopper R.I.P 5-13-2017; 02-06-2017 at 06:22 PM.
My Nomad had brand new rubber bushings that I installed in the a-arms and they were all cracked and nasty looking when I pulled the chassis out from under it. They never saw sunlight and were indoors all the time but looked like crap. My Polygraphite bushings have to be over a decade old now and still look like new. I have a bunch of extra left-over poly bushings I bought cheap on eBay a long time ago too, no telling how old they are but they look new too. My old rubber body mounts were new when I installed them and they were trashed (smashed, cracked, deformed) when I took them out. After sitting for several years with the body on, my poly body mounts still look new. I'll stick with polyurethane for now. I think it holds up to the elements better than rubber based on my experience.
56 Nomad, Ramjet 502, Viper 6-speed T56, C4 Corvette front and rear suspension
Other vehicles:
56 Chevy 2-door BelAir sedan
56 Chevy 210 4-door sedan
57 Chevy 210 4-door sedan
1962 327/340HP Corvette
1961 Willys CJ3B Jeep
2001 Porsche Boxster S
2003 Chevy Silverado 2500 HD Duramax
2019 GMC Sierra Denali Duramax
To your point, if there is in fact a "Shelf Life" attributed to these products, has anyone seen it? I can't say that I ever have. To parallel the experience, recently I was going to utilize some old bushings that came with some RideTech shock units (very old - ten years) and discovered the very same phenomenon - powdered and crumbling. Have things changed that much with these poly compounds? Should those with older bushed cars be concerned?Originally Posted by rockytopper
I don't think anything has changed. I had a Stanley dead blow hammer come apart the same way a few years ago. It just started crumbling. I've also had shoes with urethane soles do the same thing.
What I don't know is what compounds and chemistry are typically used in automotive bushings or how many variations there might be - or how to quickly tell what you have. What I do know is that I worked in an industry that uses a lot of urethane materials to make products water resistant and tough. Generally the most durable stuff was molded or extruded polyether based polyurethanes. Polyester based polyurethanes are slowly attacked over time by moisture. There are also 2 part compounds which run from junk to excellent, but they are also susceptible to mixing errors and moisture in the catalyst.
So there are a lot of choices and a lot of ways to go wrong.
I restored my cutlass in 2010 with all new door and window seals that were suppose to be soft seal products purchased from OPGI. The door seals have held up but the vent seals are junk. They crumpled and turned to powder in less than 3 months after I installed them. I think company's are just selling us junk these days. I would be far better off if I had left the 45 year old seals in the car.
My $45 Snap-On test light with the coiled rubber lead went to hell in 5 years sitting in my tool box.
That's just bizarre, IMO. I've never seen anything like that with poly bushings.
56 Nomad, Ramjet 502, Viper 6-speed T56, C4 Corvette front and rear suspension
Other vehicles:
56 Chevy 2-door BelAir sedan
56 Chevy 210 4-door sedan
57 Chevy 210 4-door sedan
1962 327/340HP Corvette
1961 Willys CJ3B Jeep
2001 Porsche Boxster S
2003 Chevy Silverado 2500 HD Duramax
2019 GMC Sierra Denali Duramax
Was talking to my pop about polyurethane crumbling/deforming. He does machine work with delrin frequently (white, black, and the brown stuff, called AF...has teflon in it), but no poly (can't really machine polyurethane). Poly will change shape over time...it's soft enough that constant pressure on it will deform it. In suspension, especially where things are rotating, it'll ovalize over time..hard to say how long. As far as bushings coming apart...he's wondering if it's because of chemical reactions with grease. I know plenty of folks like it and have had good luck with it, but I don't trust it. .I'm sticking with delrin on everything except my sway bar bushings and body mounts.
Poly Bushings,
Sure seems very strange to me that Poly suspension bushings failed. I've had them in my '56 for 10 years with no issues, not ever those pesky Squeaks. Not the first Car that I've used them on. Question is, with so many Junk parts on the market, are all the makers actually using the material components that they claim ?? Prob Not.
As far a Creep in Delrin, that's news to me in this application. Nylon of course does.
BTW, I installed new OEM rubber bushings in my C4 Convert in 2000 during the resto. Only 8000 miles heated garage are their hard and when I changed the wheels and tires the last Fall, this Car did Not settle back to ride height. Time to change...
In the build that I've just started with C4 suspension, the Front control arms will utilize Del-a-Lums, everything else are spherical rod ends. No more rubber bushing for me....
Question, whats the best means to remove these old hard rubber bushings ??
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