Posted by Clint Dixon [172.68.58.26] on Saturday, October 07, 2017 at 09:26:18 :
In Reply to: When Did Dual Wipers Begin?... posted by Steve [108.162.219.37] on Thursday, October 05, 2017 at 22:28:59 :
The very first parts list - #D-11112, titled 1946 Dodge General Purpose Truck Model WDX Advance List of Parts, dated November 1945, and sent out to dealers on December 17, 1945, lists only a left side vacuum wiper motor assembly, part number 787 915.
This advance list was quickly superseded in December 1945 by #D-11091 - 1946 Dodge Power Wagon Preliminary Parts List Model WDX which was sent out to dealers on March 6, 1946. It too lists only a left side wiper motor assembly 787 915.
The very next parts list did not become available until a couple of years later - #D-12004 revised February 1948 and sent out to dealers on April 13, 1948. It superseded the previous #D-11091 and was titled Dodge Power Wagon Parts List Model Series WDX. It was the first Power Wagon parts list to include a right side wiper motor assembly - part number 787 914. In addition to the newly listed right side motor, this parts list also included a listing for an optional electric windshield wiper package - part number 921 246. This electric unit was not noted as having never been listed previously for Dodge trucks, it was simply the first time it appeared available for Power Wagons. This would imply that it had previously appeared in one or more Dodge 2WD truck parts lists. Also of note is that this electric option had no left or right designation.
These parts lists do not give a definitive answer to your question. However I believe they show that the earlier the WDX was produced, the more likely it was to come from the factory with only the left side wiper motor.
Junior