Dr. side wiper arm problems?

[Jerky Arm Ape]

My driver side wiper arm attempted to self eject on my way to work this morning.
They were both working fine then the Dr side flopped over and hit the door mirror at the speed of light then that was all she wrote....

It's really hard to push it back down to resting position and does the same thing if you turn it back on.
No movement present once it rests on the mirror.

I've yet to have a problem out of my wiper system on these trucks, not familiar with the system.
What do I need to look at?

 

[Jerky Arm Ape]

98 yukon 4 door

 

[SunlitComet]

based on the parts list that has to the left arm linkage or arm pivot mount. this assumes the right arm is normal in all respects. parts 1, 8 or 12 i think. once you remove the arm and the cowl i think it will be readily apparent.

http://www.gmpartseast.com/chevy/co...stem-windshield-tc160480116-l31m30k10706.html

 

[Jerky Arm Ape]

Ok. Part of the problem was not being sure how to access it.
Will pull the cowl when I'm off and check it out.

 

[Jerky Arm Ape]

Ended up being the part of the transmission that mounts to body broke off.
Factory transmission had a plastic housing.
The replacement had a metal housing with new bolts.
It's back in business.
Thank you for the help.

 

[SunlitComet]

sorry, i thought that was incorporate in the other parts i mentioned.