I just picked up a 1978 model year John Deere 400 lawn & garden tractor with 133 original hours on the OE Kohler K532.
I know oil technology has come a long way since 1978 as the manual states SAE30 in the summer, and 5W30 or 5W20 in the winter. Looking for some alternatives to the straight 30.
It came with the mower deck, frt. plow, and frt. snowblower so it will be used year round. Plan on changing out fluids soon before using, can I go with a heavy duty 5w30 whether synthetic or conventional such a diesel oil or 5w40 with strong additive pack year round? Any experience or suggestions?