Crankcase Vent Modification for 24V Dodge Cummins Trucks People been asking for me to redo this article so here it is. Supplies you'll need... 1 stick of 1/2" PVC pipe (minimum of 57" long) 3 - 1/2" PVC elbows slip to slip 1 - 1/2" PVC elbow slip to NPT (male or female) 1 - 1/2" PVC straight connector slip to NPT (male or female)