My 1982 odometer failed last week. It has 420k km and is original. I beleive a friend whom I loaned the car has pushed the odometer reset while driving. I reset the odometer counter myself while stopped, every time I put gas.

Has anyone used some kind of lubricant compatible with nylon or plastic ?

I have repaired the split 18 teet nylon gear with metal rings each sides. Although the gear is very tight on shaft it does slip when bottom counter changes from 0.9 to 1.0 or 9.9 to 10.0 km. This makes me beleive that bottom counter may be damaged or could be helped with a little lubricant.