As a general rule, the shaft area of your Graco T3 Pump should be checked, cleaned and lubricated every three to six months. When you get a new T3 Pump and during these checks, run about 20 gallons of material. Afterwards, tighten the packing nut by hand and then use the included spanner wrench to tighten an additional 1/8 to 1/4 turn.