S4 GTU noisy drivetrain
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S4 GTU noisy drivetrain
I want to run this by you guys. Here is a video I cut out that picked up noise from the drive shaft. The noise only exists taking turns at low speeds. The diff has been rebuilt with a preload of 90ft-lb. I know these are known to be noisy with preload I just want to hear what you guys think before I start taring into the trans. This is a 1988 gtu.
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Thanks for the reply K-Tune.
I really had nothing as a comparison, a buddy of mine has a welded diff and his wheels skip and my car has a pre-load of 90lb-ft before the wheels break. It does a good job on the track, its low speeds as you've heard that really concerns me. Last time on the lift I turned the shaft by hand and noticed that the wheels would be spinning before i hear clung coming from the transmission.
It almost sounds like the drive shaft is skipping teeth.
I really had nothing as a comparison, a buddy of mine has a welded diff and his wheels skip and my car has a pre-load of 90lb-ft before the wheels break. It does a good job on the track, its low speeds as you've heard that really concerns me. Last time on the lift I turned the shaft by hand and noticed that the wheels would be spinning before i hear clung coming from the transmission.
It almost sounds like the drive shaft is skipping teeth.
That doesn't sound like wheel break to me, at least not what I remember from my buddys welded diff. It sounds like something is scraping when you turn. Is it low speed or is it just how much you turn the wheel?
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Its only at low speeds and it doesn't matter on how big of a turn I make the sound is pretty constant. The diff has been shimmed. Could it be a slack between the drive-shaft and transmission?
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I figured out what my problem is with the diff, it is completely locked. I remember testing the preload when I first built it, it was at 90lb, now I cant even break the wheels with my torque wrench rated at 150lb. Can the diff ever fail in locked up position?




