[Help] Could this be a failing diff? (video)
#1
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i made a similar thread on the miata subreddit but i'm casting my net wide here in hope of some wisdom
Video showing the noise with the car on jacks;
This noise has been present for around 6 months and has been slowly getting louder over time.
I did a differential fluid change but there was no change in sound (that video was taken AFTER a diff fluid change). Although during said change i noticed a few very tiny metal shards on the magnetic plug and the oil did have some silver swirls. This differential was an LSD from the first year of the newer design lsd (Tochigi-Fugi unit)
the transmission fluid was changed about 10 months ago and the removed fluid didn't look bad.
I checked for wheel bearing noise but i don't think that's it, neither of the drive wheels make noise when spun by hand and neither are wobbly.
i'm kind of hesitant to drive it now out of fear of potentially causing further damage.
what should i do to diagnose this?
note: the noise depends on speed ONLY. it doesn't get louder or softer while under acceleration or deceleration beyond just generally getting louder the faster i go, and it doesn't go away when in neutral or with the clutch held down
Video showing the noise with the car on jacks;
I did a differential fluid change but there was no change in sound (that video was taken AFTER a diff fluid change). Although during said change i noticed a few very tiny metal shards on the magnetic plug and the oil did have some silver swirls. This differential was an LSD from the first year of the newer design lsd (Tochigi-Fugi unit)
the transmission fluid was changed about 10 months ago and the removed fluid didn't look bad.
I checked for wheel bearing noise but i don't think that's it, neither of the drive wheels make noise when spun by hand and neither are wobbly.
i'm kind of hesitant to drive it now out of fear of potentially causing further damage.
what should i do to diagnose this?
note: the noise depends on speed ONLY. it doesn't get louder or softer while under acceleration or deceleration beyond just generally getting louder the faster i go, and it doesn't go away when in neutral or with the clutch held down
#5
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Sounds like a bad diff to me, bearing noise from a failed carrier bearing is my guess. If the metal circulated around in tiny spec, gears are probably ok. If there's pieces, the face of the gears could be damaged. Likely could be rebuilt, you would have to disassemble to inspect and see what's bad.
I have a used diff in the classifieds for cheap that doesn't make any noises (MSM torsen, strongest torsen for a miata), but you would need MSM axles to run it. There is a guy on m.net that has them paired with a more expensive MSM diff he has listed for sale.
I have a used diff in the classifieds for cheap that doesn't make any noises (MSM torsen, strongest torsen for a miata), but you would need MSM axles to run it. There is a guy on m.net that has them paired with a more expensive MSM diff he has listed for sale.