On Mon, 30 Sep 2019 15:10:41 +0100, Michael Chare
wrote:

The wiper blade arm on my car is very hard to remove from the motor
spindle, possibly because that part of the arm is aluminium and the
spindle is steel. Would greasing the spindle be wise and would it make
much difference waht grease I used?

Are you talking about once off? The problem is that they need to be
held on there firmly as any small movement that starts will very
quickly get worse. I guess you could use a drop of Copper grease to
stop the water getting in but I'm not sure if it would be recommended.
It also might mean you could fit the arm tighter as the same torque
setting on the retaining nut might result in a tighter fit on any
taper and so might make it even more difficult to remove in time?

I think I have used Copper grease but only in instances when it was
very obvious that there was a reasonably sized spline and both faces
were in good condition.

If not, something like Plus Gas would help you remove it but you may
also need a puller.

Cheers, T i m