Looking for a military motorcar. Looking for it to be ww2 dated 41-45. It can also be pre war .

Didn't know the military had their own motorcars. Other than paint, I have no idea what would make them different than regular production units. The Library of Congress may have a tech manual from 1953 to compare motorcars of that era. Was the A5ZU-A2 in production during the years you are looking for? Alas, I'm not a putt putter.

55-2004 Railway Motor Car Maintenance Multi-Gage 8-Man, 4-Wheel Fairmont A5ZU-A2 War Department Aug. 1953 95 p.

Maybe the Multi-Gage is what was specified for military service. I doubt any Class 1 railroads would order any but some shortlines or government entities may have acquired some as surplus. Good luck.