US Patent 8007398 Multi-speed transmission having at least ten speed ratios

A transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices include clutches and brakes. The torque transmitting devices are selectively engageable in combinations of at least three to establish at least ten forward speed ratios and at least one reverse speed ratio between the input member and the output member.