Diesel Conversion Specialists

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.

2003-2010 Diesel trucks require use of the existing throttle pedal. Open this article to see how we identify these pedals to ensure you get the right pedal assembly in your conversion kit.

Ford 5R110 custom transmission tuning is fully supported.

The biggest advantages of using the Ford factory TCM is that you keep the tow/haul functions, retain your factory diagnostics with regard to the transmission, and the stock shift quality adaptive function is retained. We recommend our tuning services for the Ford TCM to assure proper transmission operation and to get the most from your conversion. Be certain to complete your conversion, per our instruction manual before driving your truck.

The 1999-2003 Ford 7.3 Diesel 6-speed works well behind a Cummins engine. Ford started using this transmission in ’99. If your truck did not have one of these transmissions originally you may want to consider using a ZF6, especially if you are planning to use your truck for heavy trailer pulling. They are rated for 520 ft/lbs of torque.

ZF6- Ford started using this transmission design in ’99 and they work well behind the Cummins. They are rated for 520 ft/lbs of torque. Our adapter plate for this transmission uses the Ford 6.0 starter, so no grinding of the transmission or engine block is required for starter clearance.

It is possible to use the Ford 6.0 single mass clutch with our custom flywheel. Some stock application 6.0’s have a dual mass clutch these will not work. The best option is to use a Ford 7.3 ZF6 clutch with the proper flywheel all of which is included in the complete conversion kits.

Whether you have a 2003-2010 Ford truck that already has the 5R110 automatic or you are considering a transmission swap- find out all the particulars on using this transmission behind a Cummins engine.

This adapter plate kit uses the 6.0L Ford Power Stroke starter. This is actually the same adapter that was designed for the 6.0L 5R110 automatic transmission and it also works for the 4R100 allowing you to use the same adapter plate if you choose to switch to a 5R110.

There is a split between the 6.9L and 7.3L diesel engines in the late 1980's. Using model years as a general guide is usually a good way to judge which transmission you have.  However model year can not solely be relied upon.

We offer transmission adapters for the following Chevrolet and GMC Transmissions:

TH350, TH400, 700R4, 4L60E**, 4L80E, Chevy Allison 1000 5&6 speed automatics

 **Some 4L60E Transmissions use a 300mm torque converter. If your 4L60E transmission has a bolt hole at the top of the "tent" of the bell housing you have a transmission that will require our300mm flex plate option.**

When using a modern automatic transmission behind a Cummins, aftermarket transmission control will be needed for proper transmission operation. Find out more in this article.

If you have a 4-speed manual or 3-speed automatic, swapping in a 5-speed manual is something to seriously consider. The earlier transmissions were tough, but they simply were not designed for the torque the Cummins engines produce. Their input shafts are smaller, the clutches are smaller, and without an overdrive you will lose all reasonable fuel economy at highway speeds due to running the engine at such high RPM's. 

Some guys say the Ford ZF-5 is a better transmission than the Dodge NV4500 and others say just the opposite. That debate aside; from a conversion standpoint the ZF-5 is better and easier- this article explains why.