Lubricants

Synthetic oils have a lot of advantages over conventional, or mineral oils, the synthetic base stock allows the oil to be formulated more exactly than with a mineral base, this results in improved wear, deposits, oil consumption and friction characteristics.
however Synthetic oils do cost more to produce, but if you want to give your equipment the best, operate your vehicle for longer between oil changes, or work the vehicle hard then it is certainly worth spending the extra money.