Hi Pierso,

I'm unsure of the specific design of the 900-series wiper motors.

You probably read this FAQ page in wipers:
https://www.brickboard.com/FAQ/700-900/ElectricalWipers.htm

Yet the spindles (or drive shaft) to which the wiper blades secure pass through a housing. At the bottom end of each spindle is an eccentric cam to which the cable secures.

The rotating spindle passes through a housing. The rotating spindle and housing need some manner of lubricant in time as the factory pressed in grease dries out.

See Art Benstein's video. Makes me laugh, the honking sound:

Volvo 240 wiper drive needs lube

https://www.youtube.com/watch?v=i98fHSExTf4

You can drop the wiper drive shaft / spindle down, and repack with grease.

With wiper arm removed, I drip down some Mobile 1 15 W 50 between the spindle / drive shaft and the housing and operate the wiper motor to enhance capillary action so the oil gets sucks into the space. Though maybe better to remove, clean, and treat with grease.

Hope that helps.

Questions?

Happy Holidays.

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