ZF5 Manual Transmission- 1987-94 Rated for 420 ft./lbs. 1995-97 470 ft./lbs.
These transmissions work ok behind the Cummins, but the gas versions may have wider spacing in the gear ratios than the diesel versions. If you are planning on high performance upgrades, consider a 6 speed swap- as the Cummins will produce more torque than this transmission is rated for.
E4OD Automatic Transmission- Unless it’s a Bronco or a F-150, this is what your truck has now if it is a 4 speed automatic. Substantial grinding to the bottom of the bell housing is necessary to fit the 15.25" Dodge Cummins flexplate. You may want to strongly consider the use of a diesel version of the E4OD transmission. The diesel bell housing is larger and doesn't require the afore mentioned grinding to fit the flex plate.
We recommend that you have performance upgrades done to this transmission if you will be doing heavy towing or making performance upgrades to the Cummins engine. You should at least consider using a diesel (7.3) torque converter even if you are planning on using a stock engine.
Starter/Adapter Plate Kit Options:
1331 : 2003 - 2007 Ford 6.0L Power Stroke Starter which does not require any griding to the transmission bell housing.