[Jack Houpe]

I see a couple different places that you can remove the drain plug for the series 60, the most obvious one is at the rear of the drain plan at the lowest point and has a square head to put a wrench on. It looks like its never been removed also the others have female 1/2" drive on the plugs but I can not loosen one single plug, I'm using a 1/2" breaker bar and they will not break loose. Any suggestions? On my 6 71 Detroit I had the quick quarter turn valves with a 12v reversible oil pump to remove the oil and refill it so I purchased the same valve to replace it 3/4 NPT original plug.