Check the pump stator, for bushing wear. When u take the pump apart for inspection their are to marks on the gears, the will be facing up and have to stay that way. Check gears for wear and the pump body for any signs of deep scratch marks. The two tabs that engage the torque converter are known to wear. if everything is good install a new pump body bushing and seal. To be honest if yer gonna take the pump out ya may as well buy a rebuild kit and have at er.