Have a ticking noise under the hood that speeds up with acceleration, loud some. on 2007 Ford F-150

Local ford garage says there is a tech support that declares it is not abnormal and to do nothing about it.

Asked by for the 2007 Ford F-150
I don't agree that this is normal, it sounds like noisy lifters. How often do you change your oil? If the oil gets too old it hardens and plugs the valve train lifters, so check that first and foremost. How is your oil pressure? It also needs to be verified, because low pressure can also cause noisy lifters.
Having same problem 07 ford 162000 started ticking the other day. Changed oil every 3000 to 4000 mi Do you have any idea of the cost to change a lifter repairs?