According to the information that I have available to me, the Powertrain Warranty covers the engine, transmission, transfer case and axle assemblies on light duty vehicles.
The engine coverage includes: All internally lubricated parts, the entire pressurized fuel system (in-tank fuel pump, pressure lines, fuel rail(s), regulator, injectors and return line). Also included are all actuators and electrical components internal to the engine (i.e.: Active Fuel Management Valve Lifter Oil Manifold, etc.) as well as the Engine/Powertrain Control Module, module programming, cylinder head, block, timing gears, timing chain, timing cover, oil pump/oil pump housing, OHC carriers, valve covers, oil pan, seals, gaskets, manifolds, flywheel, water pump, harmonic balancer, engine mount, starter motor, turbocharger and supercharger. Timing belts are covered until the first scheduled maintenance interval.
Exclusions: Excluded from the powertrain coverage are sensors, wiring, connectors, engine radiator, coolant hoses, fans, coolant and heater core. Coverage on the engine cooling system begins at the inlet to the water pump and ends with the thermostat housing and/or outlet that attaches to the return hose. Also excluded are engine oil cooling hoses and radiators.
Transmission/Transaxle Coverage Includes: All internally lubricated parts, case, torque converter, mounts, seals and gaskets as well as any electrical components internal to the transmission/transaxle. Also covered are any actuators directly connected to the transmission (Slave cylinder, etc.) as well as any Transmission Control Module and/or module programming.
Exclusions: Excluded from the powertrain coverage are transmission cooling lines, hoses, radiator, sensors, wiring and electrical connectors.
The Transfer Case Coverage Includes: All internally lubricated parts, case, mounts, seals and gaskets as well as any electrical components internal to the transfer case. Also covered are any actuators directly connected to the transfer case (Slave cylinder, etc.) as well as encoder motor, transfer case control modules and/or module programming.
Exclusions: Excluded from the powertrain coverage are transfer case cooling lines, hoses, radiator, sensors, wiring and electrical connectors.
The Drive Systems Coverage Includes: All internally lubricated parts, final drive housings, axle shafts and bearings, constant velocity joints, propeller shafts, universal joints, wheel bearings, front and rear hub bearings, locking hubs, mounts, supports, seals, gaskets as well as any electrical components internal to the drive axle. Also covered are any actuators directly connected to the drive axle (i.e.: front differential actuator, etc.) as well as any transmission control module and/or module programming.
Exclusions: Excluded from the powertrain coverage are drive system cooling, lines, hoses, radiator, sensors, wiring and electrical connectors related to drive systems.
To confirm warranty information about any of your particular situations, you will want to contact the warranty specialist at your local General Motors dealership.
Michelle, GM Customer Service