Moen faucet arm will not swivel will lubrication with silicone gel or DW 40 solve the problem if the o rings are not broken

You need to remove the handle and the cartridge, check the O rings if OK, clean and apply some silicone gel no DW 40, but I would suggest to replace the cartridge at this stage, and don't forget to flush the valve, good luck.

John

Moen guaranteed for life. Call 1-800-BUY-MOEN for proper O rings.

By DW 40 I assume that you mean WD40. WD40 is not a lubricant. It is a water displacement fluid, formula number 40, hence the name WD40. It is a corrosion and rust inhibitor. It is great stuff but is is not a lubricant. It appears to lubricate at times but that is only because it is a liquid when applied. It dries to a sticky film.

Nor is it very logical to use a water displacement product in a water faucet.