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Old 10-07-2011, 07:34 AM
njayellis njayellis is offline
 
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Default 944 Turbo Wheel Vibration

I get a heavy vibration on my 87 944 Turbo on the drivers side front once I hit about 50, and it only goes away once I turn or apply the brakes - any ideas? I checked for play like a pre-race tech inspection and it seems pretty tight so I don't think it's the bearings.

FYI - I bought the car about a year ago, and the front tires have worn very unevenly, mostly on the inside.

Thanks,
Jay
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Old 10-07-2011, 07:57 AM
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Trak Ratt Trak Ratt is offline
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Prolly ballance. Try swapping sides and see if it goes away. Should also inspect wheel/tyre for damage when you have it off


BTW 944s should havae 0 play in the bearings.
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Old 10-07-2011, 09:24 PM
jerome951 jerome951 is offline
 
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Move the tires to the rear to see if the vibration moves, if not, start checking your suspension and steering components (tie rod ends, ball joints, strut top, control arm bushings, etc.)

What's your front camber and toe? Could be causing the inside wear.
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Old 10-08-2011, 10:11 AM
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Since you have eliminated the wheel bearing, my guess is it is either an out of balance or messed up tire. The other likely possibility is worn components associated with the lower control arm (castor block, ball joint, tie rod end) The uneven wear you are seeing is not right.

Get the car elevated but resting on it's own weight so you can get underneath and look at suspension while a buddy puts a breaker bar on one of the lugs and moves up and down. You should be able to see the wheel move and what component is worn. Repeat with the wheel suspended but resting on the contro arm to check for a worn ball joint. If nothing is evident take it to an alignment shop of find someone with a set of strings to do an alignment.
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Old 10-09-2011, 08:52 AM
njayellis njayellis is offline
 
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Thanks for all the advice, and here's what I've found so far:
1) Left tie rod end is shot (boot split)
2) Right inner sway bar bushing shot
3) Car appears to have positive camber, as outside of both tires worn significantly

So I ordered new tie rod ends and inner & outer sway bar bushings, and will replace the tires and get the camber and toe adjusted to spec and also check for other play as suggested.

I have 7.5x17 on the front 9x17 on rear, so can I go to 245x45s on the front with 7.5s? I had 8x16s with 245/45s all around on my last 951 and that was a great setup, so any suggestions for tire sizes with my current wheels?

Thanks,
Jay
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Old 10-09-2011, 12:46 PM
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Easiest way to tell about tyre sizing is to look at the manufacturers recommendations.easiest one of those I've found is on the Hoosier site. Their tyres cross sections run big so if they say it will fit chances are anyone’s tyres will fit the same wheel.
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