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Feels like running on grooved pavement...

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Old 06-03-2010, 01:22 PM
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WallyP

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You can cut the possibilities in half by driving in a lower gear, and seeing if the vibration is at a particular engine speed or a particular road speed.
Old 06-03-2010, 01:35 PM
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docmirror
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Steering rack loose on the shafts. Or MM as well, or a combination of many things. When the front end is off the ground, grasp the tires fore and aft. With the steering wheel in the steering lock, and key removed, push and pull on the tires while someone observes the steering rods. If they move up and down, or move much at all the bushings are shot. While in the air, try to slide a slender piece of cardboard between the oil pan and the crossmember. If you can slide a piece of cardboard in there, the pan isn't resting on the crossmember, but the MM could still be collapsed.
Old 06-03-2010, 06:22 PM
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billtool
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No thrown weights. Can't make the freakin thing do it again. Cardboard fits easily under oil pan. Can fit a pinky between the safety hooks. not quite a ring finger. Steering rack is weeping a bit. So move the tire right and left...or try in and out. Right and left there's quite a bit of play.
Merlin - left manifold is in fact restoning on a chunk of metal protruding to the rear of the car.
Old 06-03-2010, 06:50 PM
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Don Carter
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Bill,

Check that the lug nuts are tight since they were recently off when you installed new wheels.

You mention RPMs but not speed. If it's more closely related to RPMs than speed, it seems like that would eliminate tires/wheels/wheel bearings etc...
Old 06-03-2010, 07:17 PM
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Originally Posted by billtool
Steering rack is weeping a bit. So move the tire right and left...or try in and out. Right and left there's quite a bit of play.
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Bingo.
Old 06-03-2010, 07:33 PM
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billtool
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Just took it off the stands. Fired her up and the dog gone motor still rocks the tiniest bit. What's the time frame for completeting a rack bushing job? Don - I'dd throw the torque wrench on the lugs now...should have done it a month ago...
Old 06-03-2010, 07:38 PM
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About a six pack job Bill
Old 06-03-2010, 07:41 PM
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Don Carter
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Bill,

I have some left right play as well. Maybe we could do bushings on both cars on Sunday using the lift. I know you'll be in Dfw Sat but it sounds like Brads lift has a full load. If you get the Bushings from Roger while you're up there, pick me up a set too. I have an air chisel. Not sure this is the cause of your noise but sounds like we both need the upgrade.
Old 06-03-2010, 07:52 PM
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billtool
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Right on man. I "won" the bushings in last year's Third Coast raffle - sweet aluminium jobs. Drop Roger a note and ask him to bring them Sat. I'll find room in the glove box for them. FYI - just checked the lug torque. AOK at 98 lbs ft.
Old 06-03-2010, 11:16 PM
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Dean_Fuller
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If you drive at the rpm you spoke this happens and take the car out of gear...just coast...that would elminate drive train?
Old 06-04-2010, 03:39 PM
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Originally Posted by bigmac
Could a balance weight have been thrown?
Yeah most shops even if they are trusted stick the weights right on brake dust coated wheels so it's likely a weight could have fallen off...



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