I have been tinkering with the 'bad' replaced odo unit. The shaft with the brass gear on the end slides easily out, (not all the way out yet) & when past the plastic gear, turns easily.

At this point the 'pot metal' gear which is where the problem is, will not turn.
To the point of breaking off a tooth, I think, before turning. (I have not, yet)

Shouldnt it turn easily?? Is there something else that hangs up in there??

I checked the #'s, the one I used to replaced is/was from a 240d. (my car is 300cd)

Where is the gear ratio difference in these two odo units?? The plastic gears? Swappable?

-c-

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