[kpbrown31]

Do you all feel comfortable buying NOS moving parts (ball joints, control arm bushings, etc) or does some of this stuff get brittle over time? The plastic in ball joints, or the rubber in the bushings looking fine, but being more hard from sitting? Pictures look okay, but hard to tell I guess. I'm referring to various things on eBay.

I've bought NOS parts before, but nothing that's ever been a moving part. Maybe I'm over thinking it...

[tjs72lemans]

To me NOS parts are a waste of money. Overpriced. Most of the newer parts work fine. I do admit some of the older rubber parts do seem to last compared to new stuff. It's all a crap shoot.

[rustedgoat]

Some parts simply deteriorate over time. Decals, fuel pumps (diaphragms), rubber if coiled when packaged never seems to lose the wrinkles. Oem parts lasted for decades in the worse conditions, some aftermarket stuff fail on a undriven project in a climate controlled garage.

[Greg Reid]

NOS is fine for some things but suspension parts call for a lot of labor to change. It's the kind of thing you don't want to have to do over in a few months or even a couple of years... That being the case, I'd go with the best new stuff I could find.

[Shiny]

Originally Posted by Greg Reid

NOS is fine for some things but suspension parts call for a lot of labor to change. It's the kind of thing you don't want to have to do over in a few months or even a couple of years... That being the case, I'd go with the best new stuff I could find.

I like Greg's answer from a risk perspective. I'm a metallurgical eng, not a polymer guy, but....

Maybe if you discussed specific NOS parts you could benefit from others' experience with them. I think it will be hard to generalize.

Unfortunately, elastomers degrade just from sitting in air. Even though the material properties when new were well-sorted for the application, it's hard to predict how they might have changed in 50 years. Newer parts use newer materials and while the properties might not duplicate those of original, they are more likely to maintain those properties for the next 20 years than a 50-yr old elastomer.

OTH, newer materials, like thermoplastic elastomers that didn't exist 50 yrs ago, have made it easy to manufacture functional parts for less money but they might not hold up well. They are probably designed to cost less, not last longer.

When engineers make decisions about durability because a company cares about managing warranty costs, statistics typically call for a "life spec" at least 3X longer than the "nominal" requirement.

GM clearly cared about their reputation and their warranty costs so I'm confident they tried to use materials that would maintain mechanical properties well beyond their warranty period or even their "design life".

Modern aftermarket manufacturers, I dunno... but I can guess!

I think we all get it (I don't blame it on "Chinese crap" personally), but your question is a good one. Do you want "old good stuff" or "new sketchy stuff"?

I'm interested to learn how an old rubber-isolated GM suspension part holds up after 50 years on a shelf so I hope you get some comments from others that have used them.

I'm currently putting my front bumper back on and plan to use the original rubber bumper stabilizer cushions. Not as critical as a suspension part, not highly stressed in service, and probably not the same material, but they don't look bad. No cracks and still compliant after 53 years in ozone-rich Colorado air:



Mike

[Greg Reid]

You raise some good points with that bumper isolator. It reminded me that I pulled a pair of those off of a 68 LeMans for the rear bumper. They're hefty pieces of rubber and they are still in perfect condition. It's been 15 years ago and they're still on my car today.
I also have a throttle stop solenoid off of the same car and the rubber boots on it are still perfect.
I only cleaned it up. No cracks or tears.

[400 4spd.]

I prefer NOS for anything electrical or steel. We have lots of failures with repro electrical parts, none with NOS electrical and steel parts. No such thing as quality control it seems. Unlike repro stuff, OEM parts didn’t go into the box as junk. I have a local old school rebuilder do all of my starters and alternators, even though I can buy “new” for less.
I have lots of old stock rubber items I plan to use, not worried about them yet.

[6d7gto]

After finding it would not accept new grease, I took apart an NOS center link. Found everything inside to be in perfect condition (including all the plastic and rubber components). However, the grease had hardened into a glue-like substance, coating all the innards with a shellac film. The innards cleaned up nicely though.

[grandam1979]

When it comes to body panels NOS is the best you can get. When it comes to anything rubber NOS will probably be junk by this point. Just went through some NOS grommets and seals all junk one of the valve cover grommets actually shattered when I squeezed it a little.

['ol Pinion head]

Have to disagree with you grandam, have had quite a bit of nos sheetmetal go through my hands. Not all nos sheetmetal is cracked up to what it should be. Very nice used original sheetmetal has its place in the hierarchy, in many respects better than nos. As far as how small rubber parts go, it all comes down to how the part was stored.

['ol Pinion head]

Originally Posted by 400 4spd.

I prefer NOS for anything electrical or steel. We have lots of failures with repro electrical parts, none with NOS electrical and steel parts. No such thing as quality control it seems. Unlike repro stuff, OEM parts didn’t go into the box as junk. I have a local old school rebuilder do all of my starters and alternators, even though I can buy “new” for less.
I have lots of old stock rubber items I plan to use, not worried about them yet.

Zero problems here with 45-50 year old NOS tie rods & ball joints & even SELECT very nice used components that are nearing 50 years old. That is exactly the the type of suspension parts that am using in own serious restorations, all of which will see some track time.

Years ago had a disagreement on another board with fellow who is a real "gem". Just another of the "HotRods to Hell" proponents. Extolling the virtues of total cr#p bodywork & drivetrain builds, while trumpeting buying new suspension kits & parts Amused me as I've sent back a bunch of new GM A & F-body suspension parts, brake parts, & rubber parts that were absolute poor quality import pieces. His view also encompassed nos & nors engine mounts "Ahh that's junk..." something to that tune. Found that contrary to my own hands on experience along with many other serious restorers. In direct comparison, the old stock mounts were of much higher quality rubber & steel construction than what was currently available. By that time, over a 15 year period, out of two neavy boxes, i had identified & sold off several dozens of pairs of new old replacement stock 60's/early 70's V8 engine mounts. All of those mounts were loose & had been stored since coming out of a GreenLight Auto store in 1977. To this date, have not had a single complaint from a single buyer, many have been, & are repeat customers.

Properly storing of any rubber or plastic part is of importance. That doesn't mean storing such parts in a tin grainery where the sun beats down & cooks everything . Similar deal storing rubber or plastic parts in attics where temps can hit 130 degrees.