I just replaced the 3rd member of my rear differential with a "new one" (not new, but front the FRONT of another Zuk that was so unused the gears showed no use at all) in order to stop what to ME sounded like differential whine.
The car still makes what sounds like about the same level of whine with the "new" gears (maybe slightly less, and starting at a slightly faster speed, but it could be my imagination) as with the old.
I posted here ( https://www.suzuki-forums.com/suzuki-...tml#post728937
) and another thought it was the transfer case
making the noise, but then someone else rode w/ me in my Zuk and said that to HIS ears, it's STILL differential whine.
He said setting up the ring and pinon is VERY, VERY picky, and even 0.001" can make a world of difference, so maybe I screwed it up.
When disassembling the "new" differential I didn't disturb one side of the threaded adjustment ring at all (I left it in position in the housing threads where it was from the factory), and after swapping the side gears (to match the rear axle spline pattern), set the other side adjustment ring for 0.004" of ring-gear backlash, and maybe 0.002" side-play or less. Naturally, I didn't touch the pinion shaft adjustment (crush ring), and left the pinion nut in-place. (My "old" differential w/ 160k miles on it had almost 0.008" gear backlash, and corrosion/pitting on the ring gear, BTW.)
It would seem that what I did hopefully put the gear relationship almost exactly
back where it was in the differential before I swapped side gears.
Does this sound like a flawed way to replacing and adjusting the differential gears after removal that could cause as much whine as I described in the other post?
BTW, on a "lark" I just bought a used transfer case the seller swears was dead quiet, so I figured if it makes the SAME noise, it HAS to be the transmission, but then the passenger who now weighed-in is re-blaming the differential, so I am experiencing doubts.
I have no experience with the difs and gear boxes in these vehicles to know how "silent" they were from the factory, or how prone to wear and noise they were after a lot of miles.
Mine is the ONLY Zuk I ever rode in or drove, and it came to me whining already.