Cummins to Ford 7.3 / 6.9 Diesel Automatic and Manual Transmissions
There is a split between the 6.9L and 7.3L diesel engines in the late 1980's. Using model years as a guide is usually a good way to judge which transmission you have however model year can not always be relied upon.
6.9L Diesel Transmissions
T-19 4speed Manual- Identified by case number T19 or 13-09 and have a PTO cover on both sides. You will need a 12” clutch disc and pressure plate for a ‘83-’84 Ford diesel 6.9 / 7.3 that has a T-19. You will need the 11/16” starter spacer that we provide. Keep in mind without an overdrive your top speed can be very limited, and although these transmissions have a reputation for being tough, they are not as tough as the new ZF transmissions because of their smaller input shaft.
Additonal notes: Transmission adapter kit includes a custom flywheel. You'll also need a 12" Clutch disc and pressure plate.
C-6 Automatic- You must use a Throttle Vacuum Valve for proper shift function and to prevent transmission damage. You may also need to re-calibrate the governor along with the valve body to make the shift points more ideal for the Cummins torque curve. You may not need a kick down rod unless you want a passing gear.
Additional Notes: The adapter kit includes a torque converter adapter kit. It uses a 1994-2006 Dodge flex plate, and stock dimensioned Ford torque converter. Grinding of the torque converter stud ends is usually required after the torque converter adapter is installed.
7.3L IDI and Power Stroke Diesel Transmissions
ZF5 5 speed Manual- The ZF5 was introduced in 1987. It is rated for 420 ft.lb of torque. 95 and newer transmissions are rated for 470 ft/lbs of torque.This is one of the most popular and sought after transmissions for conversions in the 80-90's model Ford conversion. In addition to being better equipped to handle the power of the Cummins engine than it's predecessor this transmission also has an overdrive gear allowing faster top speeds and lower cruising RPM's to help maximize fuel economy.
E4OD 4 speed Automatic- The E4OD is close to it's predecessor in power ratings and specs however the E4OD has an electronically controlled overdrive unit. Some people have used early E40D’s that were behind a non-powerstroke engine without an aftermarket transmission controller, however, we do not recommend it. If you do, don't expect the transmission to shift in the optimum torque range of the Cummins- since the Cummins makes it's best power and torque at a much lower rpm than the 7.3. It also is required for you to make a bracket to mount your original Ford throttle position sensor to the Cummins throttle lever. We do not currently provide such a bracket. We currently offer 2 different aftermarket control modules that work well for this conversion. Please see the conversion overview for more information.
Starter/Adapter Plate Options:
1272 or 1257: 2003-2007 Ford 6.0L Power Stroke Starter - No grinding is required when using an adapter plate designed for this starter, since the size of the starter allows better starter to transmission clearance.
Go to our catalog to order Adapter Plate Kits, or our kit builder to order Conversion Kits