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Diagnostic chart, noise & vibrations

R

Ratnest

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While trying to figure out the cause of harmonic vibrations in my 66 C-10, I had a conversation with a very elderly gentleman who once owned a GM dealership in Texas. He sold the dealership about 20 years ago. He told me of a chart he had (somewhere) that helped locate noise and vibrations in cars and trucks. Well, today he called and said he had found it and had a copy for me. The copy is so bad it's almost unreadable and can not be attached to this. It's titled "Diagnostic Chart Noise & Vibration" and on the bottom right corner it has: Motor Service June 1982 33. I searched Google with no luck. This chart is amazing as it shows speed ranges and lists noise and vibration associated with many different components at different speeds. I hope for the benefit of forum members that someone can find this chart and post a readable copy for all our benefit. And, by the way, it listed "Universal Joint Angles Incorrect" at the very speeds my harmonics surfaced. :D
 
Hey John...I just spoke to the fella that gave me the chart (page) and he said that was a magazine that lots of dealerships and independent garages subscribed to. By the way, he retired in 1984. His copy is bad too.
 
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Despite the poor quality of the chart, I decided to attach it anyway. At least you can see some of the info and note how valuable it is. Maybe this will help search it out on the internet.
 

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  • Chart 001.jpg
    Chart 001.jpg
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Here ya go.. let me know if something needs changed. The only word I couldn't read on the scanned copy was:

UNIVERSAL JOINTS ???????? OR GALLED DUE TO HIGH LOADS OR IMPROPER LUBRICATION​

I simply used the word damaged... but that's not what the original chart used?

Update: Changed "Damaged" to "Brinelled"

 
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That's a fantastic restoration. I think the word you couldn't make out might be channelled. But, damaged works well too. Thanks a lot for the work on this. I think it's a slick diagnostic tool.
 
With my magnifying glass, the computer screen light, and a cold beer I revisited the mystery word. It's BRINNELLED! :D
 
Excellent...

Brinelling

Brinelling is when needle marks appear on the surface of the U-joint cross, which is usually caused by excessive torque, driveline angle. It can also be caused by a seized slip yoke or by a sprung or bent yoke​
 
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Darn it..those beer goggles caused me to see a double N! Same goggles that caused me to misalign the driveshaft :o
 
Brinelling

Also occurs in any roller bearing when it's run dry or seriously over loaded , pounded etc.
 
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