Yes,

EDIT:If you're using the "WONDERFUL" USLD diesel;there is a possibility
that your fuel "JOBBER" has not added enough additive to make up for
the lack of lubricity in the new 15ppm fuel.(Saves Him/Her a ton of
money.) As little as a quart of Peanut/Safflower/Vegetable/Etc. oil
will make a difference.Or you could use one of the commercial
additives:Redline/FPPF/Power Service/Etc.

EDIT:Your valves are in correct adjustment??? (every 10 to 15 K miles)

Try loosening the capnuts on top of each injector one at a time to try and
locate the source.(use rags around the testing injector it will seep diesel
when the capnut is loose)
What you are doing here is taking the injector being tested offline to see if
the noise goes away.
Then the classic next is to move the noisy injector(s) to another cylinder
to see if the noise follows.

Or you could try a diesel purge first.(lubro moly product ,Diesel Purge)
You would put both the intake fuel line (from the supply pump on the
side of the Injection Pump) and the return fuel line (from the return hose
on the fitting on top of the fuel filter) into a clean container full of
diesel purge and use this to run the engine (according to instructions).