'91 CQ wiper chatter cause

[Christopher Gharibo]

I have a wiper issue on my '91 CQ that my pertain to all: driver wiper always chatters and passenger side is always smooth

I've tried replacing the blades, adjusting the wiper angle, cleaning the windshield, lubricating the pivots, taking out the whole wiper assembly and lubing & cleaning it,  adjusting my diet and changing my angle of stare to the wiper as I look at it in failure.  Nothing has worked. 

Any thoughts? 

The driver wiper used to have wind deflector which is removed. Can that be the cause? 

Why does the passenger wiper not have the wind deflector where as the driver side does?

Sorry for the deep thoughts on an idle wednesday and thank you in advance.