The figure of 3,520 GPA’s (and 723 DUKW’s) to Russia comes from the US War Department “Quantities of Lend-Lease Shipments World War 2” dated December 31, 1946. This figure represents 27.6% of GPA’s produced.
Another document, the US Department of State “Report on War Aid” records 3,510 GPA’s were sent to Russia. Other National Archives correspondence, however, confirms this figure to be incorrect.
Statistical Work Sheets from the Tank-Automotive Center (TAC) had 3,020 GPA’s dispatched to Russia by November 1, 1944, and correspondence of January and February, 1945, calling for another 500 vehicles to be boxed for export, these being overhauled vehicles. Interestingly, the vehicles were to be overhauled in the mid-west, freighted to Philadelphia for boxing, then shipped to the west coast for dispatch to Russia. In reality, the vehicles missed the trip to Philadelphia.
Unofficial reports have been published stating that 1,900 GPA’s for 1944 and 300 GPA’s for 1945 were sent to Russia.