Theo
You are absolutely correct. I meant the material
in the new bushings SS sells.
Also you are correct. The first pin that broke
exhibited classic chevron ridges as the pin cracked
and cracked again over time. The stock pin
cracked out 1/3 before come sudden failure. It
took about 4 years.
The 4140 pin also showed ridges. But as you know
4140 steel does not have the 'give' of the stock
pins. It cracked about 1/8 of the way until its failure.
The majority of the cracked pin exhibited the classic
'mercerization(???)' of the sudden failure. The steel
actually changes its structure when it breaks and
almost appear crystalline under a microscope. Of course
the load it took to originally crack the 4140 far exceeds
the load the stock pin would take. The expert said
that his opinion was that the original crack occurred
years ago. Everytime the load exceeded the capability
of the pin, it would crack again.
The problem is that all this is hidden from view by the
eye of the A-arm and the pin will function normally
until complete sudden failure.
But you are also right. We are all driving 35+ year old
cars that were based on even earlier technology. The
suspension is suspect, the brakes are suspect, it
overheats easily, under tired, leaks in the rain.
God but I'm hooked and can't wait until my car is
fixed. Is this what addiction is about?
Dave
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