I went to get some oil to deaden the growling sound my Atlas engine makes on occasion and they did not have any, but they suggested 3in1 or sewing machine oil. Is this okay or do I really need a particular oil type?
I would avoid those. They might attack the plastic gears. Get an oil that is plastic compatible. LaBelle makes some lubircants that will work.
Use only one drop. Excess lubrication only attracts dirt and ruins electrical contact. Dirt is the number one enemy of N scale power.
I use Labelle 106 and other lubricants that are specifically designed for model railway equipment.
Most definitely DO NOT USE the following : which are marked in red
Penetrating oil(house hold )
WD40 they will eat the plastic
I would ask a professional model railroader or at least someone who has been in the hobby for a long time what he would use .
I use the Labelle range of oils and ptfe grease, also greas-em graphite for my couplings. 3-in-one and WD-40 are definate no-no's.
One other safe lubricant, in my experience, is Vaseline, especially for gears. As mentioned previously, less is better. I have used Vaseline for years, and not done any harm to plastic gears or parts. I use a toothpick to apply it. :)
Petroleum based Vaseline attacks rubber. I only use lubricants that are specially formulated for model railroads which have been tested as safe.