Just replaced the odometer gears on the '88 E30 - amazing that the originals had basically dissolved into goo - really, of the 4 gears I replaced only one looked anything like a gear - the rest were in pieces scattered about the speedo side of the cluster. I just wish the replacement gears did not cost so much - but, at least now I can see how far I drive - and that may be relevant since my fuel gauge gives mysterious readings - but, that's another subject.

Oh, installation was fairly easy and would have been quick except for all the cleaning up I did while I had the cluster open.

FYI - if you decide to do this, be sure to check which type speedo you have - VDO or Moto Meter - they are different and use different gears.