130 Maintenance Front Wheel Hubs The front wheel hubs can be filled with one of several types of oil. Motor oil should be SAE 30 or 15W40. The oil can be either petroleum based or synthetic (synthetic should not be used for the Volvo axle). Axle oil, API GL-5, SAE 75W-90, can also be used. There are no set change intervals for hub lubrication. The only requirement is that if the hub is opened, the lubricant must be changed. DANGER W7001271 Failure to keep wheel bearings properly adjusted may result in accelerated tire wear, poor handling and, in extreme cases, wheel separation from the hub or from the spindle resulting in loss of vehicle control and serious personal injury or death.