Author Topic: Vibration rear at 45mph  (Read 2660 times)

Offline AmericaMade

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Vibration rear at 45mph
« on: February 14, 2018, 10:39:06 AM »
Could a vibration on the rear/drive line be a bad u-joint?
What does one look for in a bad u-joint?
After the mechanic gave this note, I took to going this speed and faster and did not notice a vibration at or above 45mph. The truck is a bit bumpy as the struts are done with which Im replacing anyway.. also rear leaf spring bushings are also needing replacement.
83’ C10 Scottsdale
1983 C10 Scottsdale 383 Stroker TH/350 Holley 850 Double pumper carb

Offline VileZambonie

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Re: Vibration rear at 45mph
« Reply #1 on: February 14, 2018, 05:43:13 PM »
You don't have struts, you have shock absorbers. If the vibration is speed dependent then shocks and spring bushings are most likely not where you should be looking. If there is noticeable play in the u-joint, replace it. If the u-joints are getting really hot or just look old, replace them.  That being said, speed related vibration can be many things. Does it matter if you are accelerating or decelerating or in neutral?
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Offline KJD

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Re: Vibration rear at 45mph
« Reply #2 on: February 14, 2018, 07:01:50 PM »
If you have a two-piece drive-line you'll want to check your carrier bearing also. 

Offline Irish_Alley

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Re: Vibration rear at 45mph
« Reply #3 on: February 16, 2018, 04:10:36 PM »
like vile said we need to know more about it. what speeds and what conditions it does it at, do you feel it in the whole truck or just the steering wheel???
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Offline AmericaMade

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Re: Vibration rear at 45mph
« Reply #4 on: February 22, 2018, 10:55:22 AM »
That is my issue I dont notice anything. When I took it in, to get a once over the mechanic said there wasvibration above 45mph. Finally I have it driving again, I dont notice anything but what I gather it could the u-joint. I manually shook that area and didnt notice any play.
1983 C10 Scottsdale 383 Stroker TH/350 Holley 850 Double pumper carb

Offline Irish_Alley

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Re: Vibration rear at 45mph
« Reply #5 on: February 23, 2018, 07:27:22 AM »
so the only reason you noticed the vibration is because of a mechanic said so? imo even if you only noticed after he said anything would be a placebo type of effect. but if you still havent felt anything i wouldnt think much about it and depending on the mechanics suggestions i would probably even start using another shop.
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

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Offline AmericaMade

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Re: Vibration rear at 45mph
« Reply #6 on: February 23, 2018, 08:37:22 AM »
so the only reason you noticed the vibration is because of a mechanic said so? imo even if you only noticed after he said anything would be a placebo type of effect. but if you still havent felt anything i wouldnt think much about it and depending on the mechanics suggestions i would probably even start using another shop.

I’ve tried to “feel the vibration” but i havent been able to. I was just wondering what it could possibly be. What could create a vibration at that speed. Ive gathered the u- joint could be culprit. when I shook, the u-joint to see if its lose. It was solid.
1983 C10 Scottsdale 383 Stroker TH/350 Holley 850 Double pumper carb

Offline bd

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Re: Vibration rear at 45mph
« Reply #7 on: February 23, 2018, 11:09:56 AM »
If YOU don't feel a vibration then there is no vibration to feel.  You can expend a lot of energy chasing a "problem" that doesn't exist.
Rich
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Offline Irish_Alley

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Re: Vibration rear at 45mph
« Reply #8 on: February 23, 2018, 01:25:34 PM »
like bd said you could be chasing something that doesnt exist. and it could be a u-joint, driveshaft, a tire, a wheel or all the above or even something in the engine or trans.
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Jon87V20

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Re: Vibration rear at 45mph
« Reply #9 on: February 23, 2018, 01:35:21 PM »
Did the mehanic make any suggestions that involved significant costs? Sounds kinda shady, man.
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