I'd put what GM wanted in it, JMO-closest now available is 85w90. The usual shifting troubles w/that model truck are the column & linkage-usually old sticky grease in the column or worn shift ears. Again, JMO as a 30 yr mechanic.


My \'64\'s in the Gallery
Pictures in my Photobucket
1964 C10 Custom Cab 350/700R4
1964 Suburban 350/700R4
1979 Ford F350 4x4 400/c6