This information refers to dropping the oil pan but the graphics do not show that. And I can't get the graphics to "copy-paste". He might have only replaced half the pump, the rotor part.

 

I am an ASE Master certified mechanic that has been turning wrenches for over 10 years. (I am now back in college because I decided I wanted a new and better paying career.)
In my experience there are quite a few people out there that are expecting to be screwed over by a mechanic; but the vast majority of mechanics are honest, hard working people. There seem to be just a few that ruin the reputation of many. I have however, worked with many other mechanics that are not the greatest at interpersonal communication.
Several times I have seen slight confusion or simple miscommunication escalate into arguments. I am guessing this is the situation with the OP. The mechanic may not have communicated clearly what he did, but he probably did the work correctly. If this is the case with the OP, I would suggest apologizing to the mechanic. He would probably appreciate it and you would both end the confrontation on better terms.

 

What?

 

Hate to say it but the pump itself on a 4.6 and 5.4 can be removed without removing the oil pan. The pump pickup tube will not come out however unless the pan is removed. By removing the front cover (timing chains etc.of course) and the two pump pickup tube 8mm bolts then prying the pickup tube down a 1/4 inch the pump will slide off the crankshaft. The oil pan gasket can be changed with the pan lowered. But it has to be cut which will work if RTV is applied at the cut after its in place. I think something else you may want to consider is first why did you have the pump changed? The obvious answer would be because the oil pressure was low or non existant. If thats true then now that the mechanic changed the pump is the pressure up where it should be? If the engine is running with better pressure after the repair then It should be clear that he actually replaced the pump. Seems like $900.00 is a little steep but if you agreed to that price and the work was done then so be it. Take care.

 

All I can say is I've seen and oil pump in a 5.4 and if that thing is shot I'd have to believe the rest of the motor is to. Those things are bulletproof.

 

I agree jethat. I'm not sure why they thought he needed a new oil pump. Unless he had some pressure issues which could mean a partially plugged pickup screen and not a bad pump or a host of other engine related things. I can only remember maybe one bad oil pump and it failed from contamination. It appeared the relief valve piston stuck from the debris.