Appologies if this has been covered elsewhere.
My rear wiper on the Sportrak was very sluggish and often stalled
necessitating getting out and giving it a shove to get it going.
Got fed up with it so I took it off to have a look.
Now, there's a small adjusting screw with a locknut where the motor meets the gearbox assy, undo the locknut and wind out the
adjuster a little, mine was all the way in almost stopping the motor, do up the locknut and refit the wiper, trim and rear window.
Sorted - one superfast rear wipe that doesn't keep stopping!