If it makes you feel any better, although I haven't used Syl-glyde in a sewing machine, I have used it in my gas clothes dryer to lubricate the shaft that the drum spins on. Suggested by appliance repair sources on the Internets. At least three years in use, no problems at all. I'd use it in sewing machine gears, though I'd keep an eye on them. It seems very similar to the Tri-Flow grease, just no PTFE. Might be a little stiffer. At least it doesn't have any lithium in it!