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Old 06-20-2009, 12:35 PM   #1
Brad
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Question Vibration between ~55-65mph

I have a nasty seat-o-the pants vibration that I feel between about 55-65mph. I don't feel it before that and it diminishes after 65 although the vibration cycle increases with overall speed. The vibration is more of a shudder that happens about 1 every second at 55-60mph and then the rate increases the faster I go yet it feels smoother the faster I go.

I've had my wheels balanced several times at 2 different shops. Could it be my driveline? I've noticed it sticks out about 1-1/2" and most dl shops recommend 3/4"?
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Old 06-20-2009, 02:54 PM   #2
Classic Heartbeat
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Re: Vibration between ~55-65mph

Could very well be your problem. Didn't you tell me you have a single piece driveline? What is the diameter? WES
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Old 06-20-2009, 03:26 PM   #3
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Re: Vibration between ~55-65mph

Check the U-joints on your driveshaft.
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Old 06-20-2009, 04:33 PM   #4
1970 Bowtie
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Re: Vibration between ~55-65mph

I agree with LeddZepp,I would check the U-Jionts.Also your drive shaft may be out of balance,I would have it checked.If you replace the U-jionts and your drive shaft is not balanced correctly they will just wear out again.
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Old 06-20-2009, 10:42 PM   #5
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Re: Vibration between ~55-65mph

Firedogs 68 had a vib between 65 n 70 then the tranny went out. Replaced the tranny n torque converter now no more vibs at any speeds. Just wanted to throw that out there. But I'd check the rest of the driveline first.
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Old 06-21-2009, 03:42 AM   #6
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Re: Vibration between ~55-65mph

Brad,
Check your carrier bearing and check your drive shaft/U-joints to make sure that they are "in phase."

Larry
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Old 07-13-2009, 01:57 PM   #7
Blue'72
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Re: Vibration between ~55-65mph

Something I've recently learned.. Loosen your rear u-joint at the axle and see if it slides back and forth. The u-joint needs to fit tightly in between the nubs on the "yolk" on the rearend. If not, it needs to be replaced.
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