Fitness equipment companies typically include lubricant with the purchase of an elliptical machine. The supplied grease is what the company deems best for your specific make and model. Depending on the brand of trainer, you might use red lithium ball-bearing grease or white lithium grease. Some manufacturers also recommend 3-in-1 lubricants for the rails, which can prevent excessive wear between the rails and wheels by minimizing the amount of friction.
What Not to Use
Certain elliptical manufacturers strongly recommend that you avoid lubricating with silicone lubricate sprays or other penetrating oils commonly used for household tasks. Oils can wash away the grease from around the moving parts, which could lead to damage.