A transmission comprising: a housing, an input shaft configured to receive torque from a drive unit, an output shaft configured to transmit torque to a load, at least five planetary gearsets (132, 134, 136, 138, 140) arranged between the input shaft and the output shaft, a variable-ratio unit arranged between the input shaft and the output shaft, and at least six clutches (118, 120, 122, 124, 126, 128) arranged between the input shaft and the output shaft, the at least six clutches (118, 120, 122, 124, 126, 128) selectively engageable in combination with one another to select one of at least eight operating modes, wherein the at least five planetary gearsets (132, 134, 136, 138, 140) include a third planetary gearset coupled to the input shaft and the variable-ratio unit and a fourth planetary gearset coupled to the third planetary gearset, the variable-ratio unit, and the housing, wherein a ring gear of the third planetary gearset is coupled to the input shaft, and a carrier of the third planetary gearset is coupled to an input of the variable-ratio unit, wherein a ring gear of the fourth planetary gearset is coupled to a sun gear of the third planetary gearset, a sun gear of the fourth planetary gearset is coupled to an output of the variable-ratio unit, and a carrier of the fourth planetary gearset is coupled to the housing, wherein the at least five planetary gearsets (132, 134, 136, 138, 140) include a fifth planetary gearset having a ring gear that is coupled to the housing,, wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a sixth clutch engageable to couple a carrier of the third planetary gearset to a carrier of the fifth planetary gearset, and the at least six clutches (118, 120, 122, 124, 126, 128) include a fourth clutch engageable to couple the carrier of the third planetary gearset to a sun gear of the fifth planetary gearset, and wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a fifth clutch engageable to couple a ring gear of the fourth planetary gearset to the carrier of the fifth planetary gearset and a third clutch engageable to couple the ring gear of the fourth planetary gearset to the sun gear of the fifth planetary gearset, and wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a second clutch engageable to couple a carrier of a first planetary gearset and the carrier of the fifth planetary gearset to a ring gear of a second planetary gearset, and a first clutch engageable to couple a carrier of the second planetary gearset to the housing, and wherein a ring gear of the first planetary gearset is coupled to the sun gear of the second planetary gearset, a sun gear of the first planetary gearset is coupled to the input shaft, and a ring gear of the second planetary gearset is coupled to the output shaft. a housing, an input shaft configured to receive torque from a drive unit, an output shaft configured to transmit torque to a load, at least five planetary gearsets (132, 134, 136, 138, 140) arranged between the input shaft and the output shaft, a variable-ratio unit arranged between the input shaft and the output shaft, and at least six clutches (118, 120, 122, 124, 126, 128) arranged between the input shaft and the output shaft, the at least six clutches (118, 120, 122, 124, 126, 128) selectively engageable in combination with one another to select one of at least eight operating modes, wherein the at least five planetary gearsets (132, 134, 136, 138, 140) include a third planetary gearset coupled to the input shaft and the variable-ratio unit and a fourth planetary gearset coupled to the third planetary gearset, the variable-ratio unit, and the housing, wherein a ring gear of the third planetary gearset is coupled to the input shaft, and a carrier of the third planetary gearset is coupled to an input of the variable-ratio unit, wherein a ring gear of the fourth planetary gearset is coupled to a sun gear of the third planetary gearset, a sun gear of the fourth planetary gearset is coupled to an output of the variable-ratio unit, and a carrier of the fourth planetary gearset is coupled to the housing, wherein the at least five planetary gearsets (132, 134, 136, 138, 140) include a fifth planetary gearset having a ring gear that is coupled to the housing,, wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a sixth clutch engageable to couple a carrier of the third planetary gearset to a carrier of the fifth planetary gearset, and the at least six clutches (118, 120, 122, 124, 126, 128) include a fourth clutch engageable to couple the carrier of the third planetary gearset to a sun gear of the fifth planetary gearset, and wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a fifth clutch engageable to couple a ring gear of the fourth planetary gearset to the carrier of the fifth planetary gearset and a third clutch engageable to couple the ring gear of the fourth planetary gearset to the sun gear of the fifth planetary gearset, and wherein the at least six clutches (118, 120, 122, 124, 126, 128) include a second clutch engageable to couple a carrier of a first planetary gearset and the carrier of the fifth planetary gearset to a ring gear of a second planetary gearset, and a first clutch engageable to couple a carrier of the second planetary gearset to the housing, and wherein a ring gear of the first planetary gearset is coupled to the sun gear of the second planetary gearset, a sun gear of the first planetary gearset is coupled to the input shaft, and a ring gear of the second planetary gearset is coupled to the output shaft.