Product Overview
This ATSG GM & Allison 10L1000 TechTran manual will guide you in the complete teardown and assembly of the 10L1000 transmission with many diagnostics included as well.
The Allison 10L1000 transmission was introduced in model year 2020 for use in Chevrolet and GMC 2500
and 3500 pickup trucks utilizing the 6.6 liter turbo diesel or 6.6 liter gas engine. This ten speed automatic transmission is manufactured by GM. Allison is only a design and development partner with GM. The resemblance to the 10L90 transmission will become very obvious once it has been disassembled.
The 10L1000 is a fully automatic, 10 speed, rear-wheel drive (RWD), electronic-controlled transmission. The
ten speed ratios are generated using four simple planetary gear sets, two brake clutches, and four rotating
clutches. The resultant on-axis transmission architecture utilizes a squashed torque converter, an off-axis
pump and four close coupled gear sets. The four rotating clutches have been located forward of the gear sets to
minimize the length of oil feeds which provides for more efficient shift response.
The transmission architecture features a case with an integral bell housing for enhanced powertrain stiffness.
A unique pump drive design allows for off-axis packaging placed very low in the transmission. The pump is a
variable vane type which effectively allows for two pumps in the packaging size of one to ensure there will be
no priming issues. This design and packaging strategy not only enables low parasitic losses and optimum
priming capability but also provides for ideal oil routing to the control system. The transmission control
module (TCM) is externally mounted, enabling packaging and powertrain integration flexibility. The
controller makes use of four speed sensors which provide for enhanced shift response and accuracy.
The 4-element torque converter contains a pump, a turbine, a pressure plate splined to the turbine, and a stator
assembly. The torque converter acts as a fluid coupling to smoothly transmit power from the engine to the
transmission. It also hydraulically provides additional torque multiplication when required. The pressure
plate, when applied, provides a mechanical direct drive coupling of the engine to the transmission.
The planetary gear sets provide the 10 forward gear ratios and reverse. Changing gear ratios is fully automatic and is accomplished through the use of the Delphi T87A stand alone transmission control module (TCM). The TCM receives and monitors various electronic sensor inputs and uses this information to shift the transmission at the optimum time.
The hydraulic system primarily consists of an off-axis gear-driven variable vane-type pump next to the valve body, and two control valve body assemblies. The pump maintains the working pressures needed to stroke the clutch pistons that apply or release the friction components. These friction components, when applied or released, support the automatic shifting qualities of the transmission.
The friction components used in this transmission consist of 6 multiple disc clutches. The multiple disc clutches deliver 11 different gear ratios, 10 forward and one reverse, through the gear sets. The gear sets then transfer torque through the output shaft.
The 10L1000 is available in two and four wheel configurations as well as PTO equipped, RPO code MGM and MKM or non-PTO equipped, RPO code MGU.
The transmission used to create this manual is RPO MGM which is a PTO equipped transmission.
