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Hoboceratops · Joined: 16 Aug 2006 Posts: 156 Location: Atlanta, GA

So I've had a rattle cropping up slowly coming from my rear end. It's been pretty intermittent and I didn't usually notice it, but I had the time to check it out today.

I lifted the rear and put it on stands, then ran the car through the gears at about 1000rpm (I was pretty OCD in making the supports super-stable). Shifting into first and second there was only a bit of rattle which is usually worse on the road, then nothing until 5th. I swear, fifth gear sounded like I had a rock tumbler sitting in my trunk. I idle in 5th and hop out to find a very loud rattle was coming right from the gear box. I get a friend to bring it up to 2000rpm in 5th, and the sound smooths out and quiets, but the sound is still there.

This is kind of a slap in the face, put some synthetic transmission fluid in it just a couple thousand miles ago, and now this.

So I can only imagine I've got some dead bearings back there, right? Anything for the amateur home mechanic to do, or should I just take 'er into the shop?

Edit: I forgot to say that I know about the 5th gear rattle that's pretty common in 924s, but this is present in all gears and is much louder in first and second when on the road.
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1987 924S: Very much in love with it, even if it's all finnicky

Ozzie · Posted: Fri Mar 30, 2007 7:00 am Post subject:

Is it definitely coming from the trans?
How about rear wheel bearings or CV's? Torque tube?

Just trying to save you some pain.
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Hoboceratops · Joined: 16 Aug 2006 Posts: 156 Location: Atlanta, GA

100% positive it's the trans; specifically, the gear housing.

Bad news for me, I think.
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1987 924S: Very much in love with it, even if it's all finnicky

Mike924 · Joined: 12 Aug 2004 Posts: 2601 Location: IoW UK

If that's the case, your best bet might be to get hold of a good used G/B with a bit of life left in it. The units are expensive to fix up!
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Hoboceratops · Joined: 16 Aug 2006 Posts: 156 Location: Atlanta, GA

Excuse the ignorance, but G/B? Also, is my trans pretty much on its last legs with that noise and just waiting for a complete breakdown?

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1987 924S: Very much in love with it, even if it's all finnicky

924guy · Posted: Sat Mar 31, 2007 12:53 am Post subject:

i believe gb = gear box.

its not the end of the world, check it , but iirc you've got the same tranny as the pre 85.5 944 right? fairly easy swap , and they're not difficult to find usually. if you look around, ill bet you can one fairly cheap as well, or you could invest in an lsd set up

noises from the rear can be deceiving though, i once swapped out a four speed i was sure was shot to hell, only to find out after i still had the noise. turned out to be a bad wheel bearing. you'd think that would be obvious, but the sound was transmitting up the shafts and was actually louder at the box.. weird things can happen sometimes.

start lining up the tools you need and spraying the pb blaster now though, those cv bolts can be a bear..
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