Front diff harmonics

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audiocontr
United States of America
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Location: Buffalo NY

Front diff harmonics

Post by audiocontr »

Recall the sound of an unbalanced drive shaft, as it pulses while driving at speed, back and forth... The haflinger makes that sound. It always has. I'm positive its in the front.

Would too much fluid in the center shaft cause this?
1973 712m
1968 Haflinger
1965 Pathfinder
1978 GMC Palm Beach (Hey, its got 6 wheels!!)
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audiocontr
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Re: Front diff harmonics

Post by audiocontr »

Is it possible that its a whistle across any of the drain holes?
1973 712m
1968 Haflinger
1965 Pathfinder
1978 GMC Palm Beach (Hey, its got 6 wheels!!)
Heinkeljb
Great Britain
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Re: Front diff harmonics

Post by Heinkeljb »

I think it is far more likely to be a slightly bent drive shaft due to slightly worn fulcrum pins. That will load a bearing on one side and cause a bit of noise which then because the shaft can go up and down, the loading will change.
Lurch does the same thing, so I would guess it is quite common.

John
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TechMOGogy
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Re: Front diff harmonics

Post by TechMOGogy »

That was my 1st guess too for a noise like that - bearing(s)
72 Pathfinder | 75 710M 2.7i | 96 350GDT Worker
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audiocontr
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Location: Buffalo NY

Re: Front diff harmonics

Post by audiocontr »

Thanks gents!
1973 712m
1968 Haflinger
1965 Pathfinder
1978 GMC Palm Beach (Hey, its got 6 wheels!!)
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Jimm391730
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Re: Front diff harmonics

Post by Jimm391730 »

Check if the "pulses" happen at wheel rpm; an out of round or bent wheel will load and unload the drive train as its radius changes.
Jim M.
712W and 710M
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