HELP! Possible broken differential?
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Originally Posted by S2KPUDDYDAD,Sep 7 2007, 06:54 PM
You can PM me with your number if you need a call to talk you through anything.
, I'm getting my car checked out tomorrow and I'll let you know what's wrong with it.
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FYI: no metal on my drain plug when a whole tooth broke off. It was sitting somewhere else in the housing. If it's really the diff, it's almost not worth it to check the fluid. Save your $50 and just buy a used one. And my tooth broke off with a Comptech reinforced housing, so I'm not a fan.
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Originally Posted by CKit,Sep 8 2007, 01:04 AM
FYI: no metal on my drain plug when a whole tooth broke off. It was sitting somewhere else in the housing. If it's really the diff, it's almost not worth it to check the fluid. Save your $50 and just buy a used one. And my tooth broke off with a Comptech reinforced housing, so I'm not a fan.
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From: 17 ft below sea level.
A missing tooth of the ring gear would produce a noise that is more constant IMO.
A missing tooth of the pinion would be immediately catastrophic.
At some point in the video the noise is completely gone.
That could be beause of the recording...
Anyway.. I'm not so sure, based on the posted video, its the diff.
Please post what the problem turns out to be.
Lets talk percentages (like Adam in MythBusters ) of diff failures.
In an OEM diff & N/A car: 60% is the oil, 40% is how you operate the clutch.
With aftermarket gears & N/A car: 55% is the install, 25% is the oil, 20% is how you operate the clutch.
An incorrect install of final drive gears WILL ruin them, plain & simple.
No reinforcement will prevent that, at best it will only make them very noisy, until they fail
A missing tooth of the pinion would be immediately catastrophic.
At some point in the video the noise is completely gone.
That could be beause of the recording...
Anyway.. I'm not so sure, based on the posted video, its the diff.
Please post what the problem turns out to be.
Lets talk percentages (like Adam in MythBusters
) of diff failures.In an OEM diff & N/A car: 60% is the oil, 40% is how you operate the clutch.
With aftermarket gears & N/A car: 55% is the install, 25% is the oil, 20% is how you operate the clutch.
An incorrect install of final drive gears WILL ruin them, plain & simple.
No reinforcement will prevent that, at best it will only make them very noisy, until they fail
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From: Jacksonville, FL
Originally Posted by SpitfireS,Sep 8 2007, 09:04 AM
A missing tooth of the ring gear would produce a noise that is more constant IMO.
When my pinion tooth broke it was a very regular 'whap-whap-whap'.I've heard this same type of irregular noise from a Torsen LSD gone bad on a Miata.
And I would think that if it were a broke axle, the car wouldn't move. Since our diff will spin an unladen wheel.
But net-net...doesn't matter pinion or LSD...it's very likely the diff.
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Originally Posted by SpitfireS,Sep 8 2007, 06:04 AM
A missing tooth of the pinion would be immediately catastrophic.
Breaking a tooth is not immediately catastrophic.
The noise could be intermittent depending on load.
In the beginning, I only had a thump (that sounded kind of like that) with acceleration.
But like people are saying... a good teardown and reinstallation of a diff is more expensive than just replacing it with a used OEM.
it's the differential not the cv joint half-shaft drive axle that I'm thinking of. I guess it's time to beefed them up. 
