87 F150 seems to oversteer, pump is new and tires and alignment good, any ideas what is causing this problem, the pump does make a lot of noise......

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Oversteer? Checked all the tire psi's? Greased the Zerk's lately? Might be a bad tie-rod...

 

Is the pump making noise even when wheels straight ahead, no steering wheel input? If so, maybe the air purge procedure was not done after the pump was replaced. Usually... jack up front end so both wheels clear of ground, with engine idling, turn steering wheel slowly lock-to-lock (like 5 seconds per trip) and back again a few times. Trapped air usually works its way up to the reservoir then.