An insert for supplying a fluid to splines of a drive shaft, the insert extending along an axis of rotation, and the insert comprising an insert wall extending along the axis of rotation, a reservoir defined by the insert wall for storing a fluid, an elastically deformable portion, the elastically deformable portion capable of transitioning between an expanded state and an unexpanded state, and wherein the elastically deformable portion is configured to expand to the expanded state in a radial direction with respect to the axis of rotation when the fluid is supplied to the reservoir during rotation of the insert and to contract to the unexpanded state when rotation of the insert and supply of the fluid to the reservoir are ceased.