Oiling issue?

[KevinKrey]

I bought a new to me GP38-2 at a train show a while back, its a proto 2000 from lifelike and is in REALLY really nice shape. It came pre equiped with a DCC decoder and Ive ran it on a few pieces of small track fine here and there, but today I set up some old Bachman EZ snap track just to run some trains on till I get more code 83 switches that I ordered. Anyway, when i get it to run fairly fast, it makes a screaching kinda noise, I dont know if its a new issue or just that I havent had it running this fast yet. I doesnt run the fastest anyway, so I know its not like Im just trying to get too much speed out of it. There dont seem to be any other issues with it though and i wonder if a simlpe oiling would help. Ive always brought my locos in to a really cool guy at the LHS for repairs. Heres a pic of it with the shell off, could somebody point out a spot to try puttin a drop or two of oil on? thanks.