That is perplexing. I was going to ask if the wiper blade was stuck to the glass, but you're way past that. Would you say the rear wiper has been lightly or heavily used for its age, meaning is it more likely badly worn or seized from lack of use?

Sounds like something is binding or locking up somewhere, but only under some kind of lateral or in/out tension? If the motor runs easily it would seemingly have something to do with the linkage. With one end or the other disconnected you'd think you'd be able to duplicate a lack of movement at same odd angle.

The weak point in the rear wiper desaign in my experience is the aluminum casting through the gate. Yours looks in better shape than the one I last had out. I presume when loose off the car that the aluminum casting can be easily turned on the shaft by hand both when pulled out and especially when pushed in as if under wiper arm tension?

You've likely just come out of winter driving where salty roads spray coats the tailgate. The aluminum can easily get a bit corroded, especially if the lube becomes dry, and could in theory act like it's seized. There should be a circlip near the splines that holds the shaft in the casting. Can you remove it so you can slide out the spline for inspection and lubing? I'm not sure if there's a pressed in brass or steel bushing, hopefully not just aluminum.

With the wiper and linkage installed without being fastened to the motor, the linkage can be moved by hand such that the wiper turns? The linkage pivots should be fairly forgiving even if fairly worn as long as they're lubed with a bit of grease.




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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now