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Rear end shake

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Old 08-03-2007, 01:25 PM
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koumiss45
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Default Rear end shake

Ok when I am drving down the highway at anything above 40 mph my car shakes when I let off the gas. It doesn't seem to matter what gear I am in, although it may do it more when I am at a lower rpm, it also does it in nuetral.... it feels like the back of the car is bouncing very rapidly and shaking.... it seems more up and down than side to side. it is a medium to large vibration...any guesses on what it can be....it doesnt do it when I am on the gas.
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Old 08-03-2007, 01:41 PM
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Pest007
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Default RE: Rear end shake

I'd say tires are out of balance or bent rim
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Old 08-03-2007, 01:48 PM
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jpmustanggt
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Default RE: Rear end shake

It's got to be something with the tires or suspension I think.
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Old 08-03-2007, 01:52 PM
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koumiss45
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Default RE: Rear end shake

Wouldnt the tires be doing it at all times? And the suspension also? I was thinking it might have to do with when the drive line shifts position when i get off the throttle.
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Old 08-03-2007, 02:22 PM
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MrChubs1
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Default RE: Rear end shake

I was going to say u-joints or trans mount, but it's weird that it does it in neutral too. Is it much worse if you decel from a higher RPM in a lower gear (hi-load decel)?

Pinion angle issue?
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Old 08-03-2007, 02:28 PM
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Ryan86272
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Default RE: Rear end shake

My tranny mount is bad..... Only when i give it gas or downshift... NOT in Neutra(no Torque) Once there is any torque u can hear it Knockin I dont think his problem is the Tranny Mount
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Old 08-03-2007, 04:39 PM
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koumiss45
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Default RE: Rear end shake

I have the car lowered just a little, pro kit. Could a combination of a bad tranny mount plus this cause my issue? How can I tell if I have a bad mount, just get under it and look. Tranny mount is on top right?
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Old 08-03-2007, 06:17 PM
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ackuric
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Default RE: Rear end shake

no the tranny mount is under neath the tranny in between the crossmember and the tranny

you would know if you had a bad tranny mount, your shifts would be horrid, and you'd feel the tranny bouncing around underneath you when cruising in o/d on a bumpy road. you wouldnt call it a rear end shake, the tranny is way closer to the front, and you feel it right where you sit.

my guess is rim/tire issue.

btw hijacking the thread, our stock mounts for the trannies SUCK, give way too much play. i wonder if code has upgraded his mounts to polyurethane or solid, hmmm.
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Old 08-04-2007, 12:13 AM
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koumiss45
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Default RE: Rear end shake

Again ... wouldn't that do it all the time? How about a U joint or a carrier bearing
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Old 08-04-2007, 12:15 AM
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Default RE: Rear end shake

It doesnt seem to be rpm specific....seems to be speed of drive shaft specific...the faster that boy is turning the worse it is....and nuetral is maybe a little worse.
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