This gearbox assembly (50) for a lawnmower (10) includes a gearbox housing (56) having a horizontal input shaft (62) and a vertical output shaft (64). A lawnmower deck (12) is disposed below the gearbox housing (56) and a spindle housing (55) is mounted to the lawnmower deck (12) and the spindle housing includes a passage (57) communicating with the gearbox housing (56). The output shaft (64) extends below the gearbox housing (56) and into the spindle housing (55). The input shaft (62) has a bevel gear (76) which meshes with a bevel gear (78) on the output shaft for driving (74). The output shaft (64) includes spaced bearings (70 and 72) within the gearbox housing (56) and a bearing (74) within the spindle housing (55). Brackets (28 and 30) are attached between the gearbox housing (56) and the lawnmower deck (12) and the spindle housing (55) is attached to the lawnmower deck (12) separately from the gearbox housing (56).