A system and method to add an additional drive axle to a vehicle may include an auxiliary shaft aperture bored through the differential housing and an auxiliary shaft sleeve mounted over the aperture. An auxiliary shaft has a splined end interconnected to a modified pinion and a short transfer drive shaft interconnect disposed on an opposite end thereof, the short transfer drive shaft interconnect extending out from the modified differential housing through the auxiliary shaft sleeve. A short transfer drive shaft is operatively interconnected to the auxiliary shaft and rotational therewith. Further, an additional drive axle assembly is mounted to the vehicle rearward of the original drive axle, and the modified differential is operatively interconnected to an additional drive axle via the short transfer drive shaft, such that when the short transfer drive shaft rotates with the auxiliary shaft, the additional drive axle rotates with the original drive axle.

A kit for modifying an OE vehicle transmission includes a replacement forward piston housing, forward clutch hub and a forward clutch and a replacement direct piston housing, direct clutch hub and a direct clutch. A drum extends between and operably connects the replacement forward piston housing and direct piston housing. The kit includes a replacement sprag shaft. The forward clutch hub and forward clutch and the direct clutch hub and direct clutch are positioned between the forward piston housing and the direct piston housing. At least a portion of the forward clutch and at least a portion of the direct clutch are operably mounted to the drum. The forward piston housing and direct piston housing do not counter rotate relative to one another. A power flow module for an OE vehicle automatic transmission is disclosed.

A drop-in lube boost valve assembly replaces an OE lube boost valve assembly in a vehicle transmission hydraulic circuit. The OE valve assembly has a valve body with inlet, balancing and outlet ports. The drop-in valve assembly includes a sleeve having inlet and outlet ports, and a bore extending between and fluidically connecting the ports. The drop-in valve ports are spaced from each other. The sleeve includes valve and spring chambers. A valve has a valve face, a sealing portion and a spring stem and is positioned in the sleeve with the sealing portion positioned in the sleeve bore. A spring is positioned on the spring stem. The valve reciprocates in the sleeve between an open state in which the sealing portion does not overlie the sleeve outlet port and a closed state in which the sealing portion overlies and closes off the outlet port.

A modified cooler bypass manifold includes a manifold body having an inlet conduit, an outlet conduit, a return conduit, a thermal valve bore, a pressure valve bore and an intermediate conduit. A plug may be installed in the thermal valve bore. In another embodiment, a modified cooler bypass manifold includes an OE manifold body, a first inlet conduit, a second inlet conduit, a first outlet conduit, a second outlet conduit and a valve bore. The modified cooler bypass manifold may also include a pressure bypass valve assembly disposed in the valve bore. An OE end cap and retaining ring may be disposed in the valve bore and operably connected to the pressure bypass valve assembly and the OE manifold body.

A kit for modifying an OE vehicle transmission includes a replacement forward piston housing, forward clutch hub and a forward clutch and a replacement direct piston housing, direct clutch hub and a direct clutch. A drum extends between and operably connects the replacement forward piston housing and direct piston housing. The kit includes a replacement sprag shaft. The forward clutch hub and forward clutch and the direct clutch hub and direct clutch are positioned between the forward piston housing and the direct piston housing. At least a portion of the forward clutch and at least a portion of the direct clutch are operably mounted to the drum. The forward piston housing and direct piston housing do not counter rotate relative to one another. A power flow module for an OE vehicle automatic transmission is disclosed.

A drop-in lube boost valve assembly replaces an OE lube boost valve assembly in a vehicle transmission hydraulic circuit. The OE valve assembly has a valve body with inlet, balancing and outlet ports. The drop-in valve assembly includes a sleeve having inlet and outlet ports, and a bore extending between and fluidically connecting the ports. The drop-in valve ports are spaced from each other. The sleeve includes valve and spring chambers. A valve has a valve face, a sealing portion and a spring stem and is positioned in the sleeve with the sealing portion positioned in the sleeve bore. A spring is positioned on the spring stem. The valve reciprocates in the sleeve between an open state in which the sealing portion does not overlie the sleeve outlet port and a closed state in which the sealing portion overlies and closes off the outlet port.

A kit for modifying a transmission input housing includes an overrun piston sleeve positioned on an outer surface of an input housing inner stepped portion, an overrun piston configured to mate with the overrun piston sleeve, and a replacement forward piston housing. An inner diameter of the overrun piston is larger than an inner diameter of an OE overrun piston. A forward piston sleeve is positioned on the outer surface of the input housing inner stepped conical portion adjacent the overrun sleeve. A forward piston mates with the forward piston sleeve. The forward piston has an inner diameter that is larger than an inner diameter of an OE forward piston. Seals are positioned between the forward piston and the forward piston sleeve and between the overrun piston and the forward piston at an outer diameter of the overrun piston.

A gear train includes a first gear having teeth meshed with teeth of a second gear. Each tooth of the first gear includes a coast side and a drive side opposed to the coast side. The drive side has a pressure angle that is greater than that of the coast side. The gear train can be part of a powertrain system for a rotorcraft, and can replace a traditional gear train in a retrofit or new build. The first gear is a planet gear and the second gear is a ring gear wherein the planet gear and ring gear are in a planetary gear train configuration.

An input drum of an automotive transmission for motor vehicles is formed from a plurality of components assembled together. The input drum has a hub having outwardly extending tabs, and a clutch cylinder having internal grooves for receiving the tabs when the hub is assembled to the clutch cylinder. The hub and the clutch cylinder are arranged such that openings in the hub and openings in an inwardly extending circumferential flange of the clutch cylinder are in axial alignment when the tabs of the hub are received in the internal grooves of the clutch cylinder. The hub and clutch cylinder are assembled together by connecting elements extending through the aligned openings in the hub and clutch cylinder. An input shaft is permanently or removably attached to the hub.

A modular hybrid transmission configurable between a 9-speed configuration and an 8-speed configuration includes first, second, third, and fourth planetary gear sets each having first, second, and third elements. Seven torque transmitting devices are each selectively engageable to interconnect one of the first, second, and third elements of one of the planetary gear sets directly with (i) one of the first, second, and third elements of another one of the planetary gear sets, (ii) a housing, or (iii) an input member. The seven torque transmitting devices are selectively engageable to establish nine forward speed ratios and at least one reverse speed ratio. Upon removal of a fourth torque transmitting device, the transmission is arranged in the 8-speed configuration and the remaining six torque transmitting devices are selectively engageable to establish eight forward speed ratios and at least one reverse speed ratio.