The G56 was introduced in 2005, featuring a lightweight aluminum case and a significantly higher input torque capacity than its predecessor, the NV5600. Interestingly, both transmissions were offered simultaneously for the 2005 model year, with the NV5600 being phased out by the start of 2006. However, the G56's feat as the only manual transmission in its class would be short-lived, facing challenges from the ever-increasing torque capacities of modern diesel platforms. As the torque wars escalated, particularly with engines like the 6.7L Cummins turbodiesel quickly outgrowing the G56's capacity, the manual transmission faced a decline. The
horsepower and torque sacrifices of G56-equipped trucks became apparent over the years. The shift towards automatic transmissions in the truck segment became more evident, eventually leading to the retirement of the manual transmission option from the Ram HD lineup after the 2018 model year. Identifying the G56 is relatively straightforward, particularly as it remained the only manual transmission offered in Ram 2500/3500/4500/5500 models from 2006 through 2018. However, controversies arose around its lubrication requirements. While
MOPAR ATF+4 was listed as the required lubricant, debates emerged regarding its adequacy. Alternative lubricants, including MobilTrans SHC DC, were considered, leading to discussions on viscosity grades and their suitability. == Reliability ==