Well that will surely cause the problem! The only thing that will cause that is extra strain of resistance to move the shaft of the spindle in its housing ,or loads against the blade as it tries to sweep the glass. Nice find of the worn part!

 

My 'as new' wiper motor arrived yesterday from the States. Installed and working for only $40.00. 2004-2010 chrysler pt cruiser rear wiper motor mopar 04857931ad | eBay
I could have bought a well used second hand unit off eBay from a UK supplier for £51.00 !!!
No contest.

 

Answer is a Good Yin...