Windshield Wiper kick back when being shut off

[Don M.]

Recently I noticed and heard a clunking sound on my passenger wiper when it returns to stopped position. It gets to the stopped position and then immediately jumps up slightly and emitting a clunk sound. Actually both wipers do this but I've only noticed the sound on the passenger's wiper. 

[Formulabruce]

what IS your truck? What year ?

GM updated the transmission in these around 2004 .

 You need a complete transmission to fix this.

[Don M.]

Pardon!  My wipers are acting strange so I need a new transmission? Geez, my ashtray is full; do I need a new engine?

2002 GMC 250 Sierra full cab 4x4 diesel. 

[CamGTP]

He's just saying a possible cause.

 

You really need to remove the cowl and watch the wiper arms function. That way you can see what they are doing and if the transmission is part of the problem.

 

Don't get all smart so fast.

[Don M.]

It was a joke.