The original Alfa one piece wiper arms don't help matters either.A lot of 155 folk have replaced them with Volvo 440/460 arms as they glide better,dont miss sections of screen and blades can be renewed for less money/effort.
I've also done a nice little washer conversion on mine,with Peugot 405 washer rails mounted on the arms,far superior to the squirt all over the place effort it came with. wink
Guys, replacing the wiper arms doesn't cure the intermittent jerky nonsense that Gwynn is on about.
I had 156 wiper arms on and it was still poo. So went back to the macho looking OE 155 arms.
I find my intermittent wipe goes crazy when it's raining....good eh !!??