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Grinding Noises?

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Old 03-21-2012, 09:11 AM
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Player0
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Default Grinding Noises?

Since I bought the 86 944T last summer, I've had grinding/scraping noises under sharp cornering. It's like the tires are rubbing on the body or something is scraping on the ground. It can happen on either side of the car depending on which way I'm turning, and happens at low speeds, just when driving through the neighborhood here.

I have stock rims and stock sized tires. I don't know if the suspension has been lowered or not, but I don't have receipts for any 'upgrades' when I do for most other things so I suspect it's stock. I don't see any obvious rubbing marks on anything. I don't get the rubbing noise over hard bumps or if the car bottoms out, it's only when I'm turning, which makes me think front wheels.

I hate to ask the dumb question but, is this something normal on a 944? Or is this a symptom of a worn/lowered suspension? Is there something I can check or measure to make sure it's in line?
Old 03-21-2012, 12:38 PM
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968 GUY
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CVjoints. Wheel bearings.
Old 03-21-2012, 12:59 PM
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944Ross
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Differential could be involved too. If it hasn't changed in 9 months, I'd suspect internals. Loose CVs would have blown out by now. Wheel bearing(s) are a definite possibility. Check for excess play.
Old 03-21-2012, 02:57 PM
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mikemyers924s
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+1 on bearings. Check for excess play by simply grabbing the wheel and trying to move it laterally. (pull towards you and then push away) if it shifts around it's center, you probably need new bearings.
Old 03-21-2012, 05:44 PM
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fittrjoe
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I suspect wheel bearings as well . Clarks garage is your friend . Not a bad job to do .
Old 03-21-2012, 06:58 PM
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Thanks for the info guys. Well, I know its not the wheel bearings because I did those in the fall, they weren't too bad even when I did them, and the wheels feel good and solid at the moment. CV joints are also in good shape, I checked them out when I repacked them with grease when the bolts fell out early winter time. They're still solidly attached as well.

Differential?

I spent some time trying to get it to happen today and it happens most often when taking a sharp turn with a dip in the road. The wheels must be turning left or right and the suspension is compressing. Hitting a dip without the wheels turned doesn't cause it, at least, I can't seem to get it to within reasonable speeds.

It's not your typical bad bearing wuhwuhwuh noise either. It's a distinct sharp gktktktkt which doesn't change in pitch with wheel speed but is directly related to the suspension compressing.

Maybe something like the muffler is hitting the road. But I can't drive it and see under the car at the same time. I'm also not sure why it happens only when I'm turning.
Old 03-21-2012, 08:49 PM
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bordin34
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My 1986 944 with stock wheels does the same thing on left turns. But I know its my right CV joint begging for mercy. If I put the clutch in the sound goes away.
Old 04-29-2012, 07:51 PM
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So I was working on the car today and I noticed grooves forming on the front outside of my new tires. So now I have evidence that the tires are hitting the wheel well.

I really need to know where to start on this. Is it possible the wheels are the wrong offset or size? Is it possible that the car is lowered or that a bumpstop needs to be replaced? Should I be looking at new struts? Are there measurements I can take to figure out where the problem is?

Thanks!
Old 04-29-2012, 08:11 PM
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Clint's 944
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If you can, post a picture. It would be a really good way to see if you have the correct wheel offset and/ or lowered suspension.
Old 04-29-2012, 11:20 PM
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mytrplseven
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Start with the wheels and tires. Are the tires what are prescribed for your car? Are the wheels the original for your car? Are the wheels staggered in width? I had a rubbing problem when the tires on my 17" wheels were a bit too wide in the rear. The rubbed the outside rear fender lip when accelerating in a left turn. I used TireRack research tools to find a tire that was 1/8" narrower but the proper diameter and the problem disappeared. viola!
Old 04-30-2012, 12:55 AM
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Here are some pictures. It was getting a bit dark. I'm pretty sure there are no spacers, but I''ll have to double check.

I just assumed these are the stock phone dial wheels that came with the car originally. I have a new set of Fuchs in the shed I've been meaning to put on.

The wheels stick out a bit from the wheel well, is that normal? Or are they supposed to tuck up inside?
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Old 04-30-2012, 12:59 AM
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Oh, the tires on the car are the factory size as far as I can tell: 205/55R16 fronts and 225/50R16 rear. These are michelin pilot sport A/S tires. The old tires that came on the car when I bought this thing did it too, Kumhos of the same size.
Old 04-30-2012, 04:22 PM
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Hollywood D
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Look up in the fender well and see where it's rubbing. My guess is your car has been lowered at some point. Got any pics of the car sitting in a parking lot for reference?
Old 04-30-2012, 06:13 PM
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I don't actually seem to have any side on photos at the moment. I can get some more once the thing is down off the jackstands in say 8 weeks heh. Here's the closest I can get. These are photos from before I took possession and it has the older tires on. When the car squats I guess the tires tuck in a bit more. Those older tires look like they fit in pretty well, but they rubbed on the fenders too somehow.

If I jacked under the control arm, would I be able to mimic a bottom-out scenario? Or would the car just raise?

I also noticed that the lip of the fenders is 'tugged' on in a few spots. I gently hammered a couple areas back up in to shape. The paint was not entirely thrilled about this so I'm hesitant to do more. I'm pretty sure this was caused by the tire rubbing on the well and not vice versa.

Lets say the thing has been lowered, if I buy a new set of struts is that all I need to do to correct it? I wonder how completely out of my league doing that would be.
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Old 04-30-2012, 06:15 PM
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Oh, I found a picture of the front wheel well. Kind of shows the gaps at least.
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