I can remember back when new vehicles had vacuum wipers and they were not worth much then. Always would stop when going uphill.
I switched mine to a 2-speed electric motor from carandtruckshop.com for about $100. Replaces the original vacuum perfectly down to the knob.
Now you cannot even stop the wipers with your hand.


57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
Pix on Photobucket