Our general guidelines go as follows:
We use a maximum of 2000 RPM stall speed on trucks equipped with an 87MM turbine manifold turbocharger. If the manifold turbocharger turbine is greater than an 87MM, we recommend going with a (looser) 2200-2500 RPM stall speed. Running a more efficient stall speed is appropriate for very lightly modified trucks that still run small/ stock turbochargers. A lower stall (tighter, more efficient) converter will enhance shift feel, increase fuel economy and decrease transmission temperatures. With 2003-2007 model year trucks, a more efficient stall speed can cause a P1740 code. This code will trigger the check engine light to come on. The vehicle's computer interprets the more efficient torque converter as a dragging lockup clutch, and will trigger the OD/TCC solenoid code. This is nothing to worry about, and unfortunately one of the small cons to running a more efficient torue converter. On 1998.5-2002 VP44 equipped trucks with hot rod injection pumps/ big injectors, 1800 RPM stall speed can cause the engine to stall when initially going into gear. MPT uses 2000 RPM by default. It is the perfect balance for shift feel and allows for substantial engine upgrades without having to restall the torque converter.