1999-2003 Ford 7.3L Diesel
INFORMATION FOR ALL 7.3L MODELS
The Super Duty® 7.3L trucks are one of the easiest trucks to convert to Cummins® power. No modifications to the firewall, core support, or floor pan are necessary. The stock radiator and intercooler can all be used as is with the Cummins engine, and the fan shroud usually works with only minimal modifications. In some rare cases, it is possible to move the transmission back just enough to use an engine driven radiator fan with our custom carrier bearing mount and still retain the stock drive shaft length. Diesel Conversions® makes this bracket available to you after you have determined your stock drive-shaft has enough slip remaining for suspension travel and drive shaft compression needs.
When you buy Diesel Conversions® parts we include year specific installation instructions. This includes wiring instructions for customers using the 12-Valve 6BT or the 1998½ - 2002 24-Valve Cummins engines, or if you would prefer, you can opt to have us do the bulk of the wiring work for you by sending in your 7.3L engine harness to be modified, as we do with the 2003 and newer Cummins engines.
FORD STANDARD TRANSMISSIONS
Ford 5-Speed – Diesel Conversions® makes adapter plates for these transmissions that use the 2003-2007 Ford diesel starter and require no grinding- as long as they were behind a 7.3 diesel. We can also offer adapter plates that use the Dodge® Cummins starters for the 7.3 diesel or 460 big block 5-speeds. These adapter plates require grinding of the starter pocket for starter to transmission clearance.
The 1995 and newer transmissions are rated for 470 ft. / lbs. of torque.
Ford 6-Speed – Diesel Conversions® makes adapter plates for the 7.3 and 6.0L diesel 6-speed. These are very good transmissions for the conversion. Currently, we offer an adapter plate that uses a 2003 - 2007 Ford 6.0L Power Stroke starter for the ZF 6-speed. You will not need to grind your transmission bell housing but will need the correct starter for this application.
4R100 -This is what your truck has now if it is an automatic. It is a 4-speed transmission. If you are planning on doing a lot of heavy pulling or adding a lot of performance upgrades to your Cummins, you may want to have your transmission beefed up, and use an aftermarket torque converter. Diesel Conversions® recommends that you have performance upgrades done to this transmission if you will be doing heavy towing or making performance upgrades to the Cummins engine. Diesel Conversions® has two styles of adapter plates available for the diesel version of the 4R100 going to the 1989-2002 Cummins. If you buy yourself a Ford 6.0L diesel starter, you can use the adapter plate that does not require the grinder job on the transmission. This adapter plate uses the stock Dodge Cummins flex plate and torque converter adapters. The adapter plate has to tilt the transmission just 2½ degrees to accommodate the starter without grinding the transmission or starter (although there is a very insignificant rib that needs just a touch of grinding just behind the starter; this small amount of grinding shouldn’t affect any core value of your case and it most certainly will not affect the structural integrity either).
If you have a Common Rail Cummins, or just want to use the Cummins starter, you will need to grind the bell housing for starter clearance.
5R110 -If you want a reliable automatic transmission in your older truck that will handle the power of the Cummins you may want to consider the 5R110. These are a 5-speed that goes behind the 6.0Ll Fords. These transmissions are practically a bolt in replacement for the 4R100 (with the 5R110’s transfer case). While the 4R100 transmissions can be beefed up to handle the power, the 5R110 can handle it as is. If you can find a good used 5R110 and transfer case cheaper than beefing up your existing tranny, it may make more sense to use the 5R110. For more information, see our Cummins to Ford 5R110 Torqshift article for more information.
INFORMATION ON PARTS IN OUR KITS
The adapter plates for automatic transmissions require our torque converter adapters and use the Dodge flex plate. Manual transmissions require the appropriate Dodge Cummins flywheel.
Our adapter plates are built out of aircraft grade (6061) aluminum. This adapter replaces the existing adapter on the Cummins Engine, making a factory quality connection between the engine and the Ford transmission.
Our motor mounts are pre-drilled to accommodate for the stock engine fan (recommended). Because the Cummins engines are longer, your transmission and transmission cross member must be moved back 2” to 3”. Automatic transmission equipped trucks already have the holes in the frame to accomodate this move. The engine mounts are an excellent design with a bolt going all the way through the isolator, instead of relying on rubber and weak interlocking tabs to secure them to the frame cross member.
In some cases the front drive shaft on four-wheel drives will stretch enough to reach the front differential.
Bushing kits include adapters to put your Ford gauge sending units into the Cummins engine. Most trucks of these years require custom pieces for this, so they are quite helpful.
We offer an alternator mount that allows you to use the 7.3 alternator if you would like. The advantages of using this alternator is that your indicator light will still work as it should if your charging system should fail. If you would rather use the Dodge Cummins alternator, we can provide you with an external voltage regulator. Common Rail applications do not need the external regulator.
Diesel Conversions® sells exhaust manifolds that work much better in the conversion for the 12-Valve and 1998½ - 2002 24-Valve engines. These manifolds place the turbo in a better place for A/C box clearance than the stock variety, and also make exhaust and turbo oil drain connections easier as well.
For the 24-Valve engines, other exhaust pieces are necessary when using our exhaust manifolds to provide an adjustable elbow connection for the downpipe.
Both of these manifolds require you to re-orient your turbo housings to allow your oil drain to be pointed down correctly. This usually requires you to heat the exhaust housing on the turbo to remove the bolts and the housing so the housing can be re-oriented. Either fixing the waste gate shut or using a different waste gate actuator we can provide is also necessary because once the turbo is re-oriented the actuator will hit the engine block. Fixing the waste gate shut does not usually have any adverse effects on the engine, but we do recommend using a boost gauge to monitor and limit boost pressures to less than 40 PSI.
Diesel Conversions® also offers manifold gaskets, and new exhaust manifold to turbo studs if you would rather not try to get the studs out of your stock manifold. Also helpful is a flexible turbo drain tube that connects to the stock hose and elbow that is left in your engine block when you remove the stock drain tube connected to the turbo. If you would rather, it is possible to heat your stock tube up to bend and twist it to allow reconnecting it after you re-orient your turbo housings.
The tach kit consists of the Base, Mount, Sensor, and tach Ring. These parts are necessary to make your factory tachometer work since the stock 7.3 cam sensors cannot be used.
Most 12-Valve engines 1994 and newer already have the tach sensor base, which is bolted to the front cover at about 11:00 to the balancer. You will have to drill and tap a hole in it for our sensor mount to bolt to it. The tachometer signal can bypass the Ford PCM on 1999 - 2001 trucks only. This allows you to use 4 notches ground in the balancer to produce the correct signal pulse for the tach to work.
If you have a Common Rail engine, or do not wish to do any grinding on your balancer, you can purchase our tach ring. Bypassing the Ford PCM will require you to do some wiring down at the Ford PCM, and if you would like cruise control you will be dealing with some other wires at this connector as well.
All trucks 2002 and newer require a different tach ring that bolts onto the front of the Cummins crankshaft balancer. This tach ring is necessary for the sensor to send the correct signal pulse to the Ford PCM that makes the tachometer work.
If you have a laptop computer we recommend the PCS controller.
The Compushift controller for the 4R100 is user friendly and does not require a laptop computer. It comes with a programmer / display box that provides you the ability to make adjustments.
Read our Automatic Transmission Controller article for more information.
AIR FILTER KIT
Our air filter kit includes a Brute Force air filter; pipe, and hose to connect to your turbocharger. We offer two styles of air filter kits. The kit the 7.3 liter truck will most likely use DCS Part #1942. It requires relocating the passenger side battery to the driver’s side. This takes some fabricating skill to make the brackets to mount the passenger side battery tray and another one just like it on the driver’s side, but it provides a nice roomy area for the air filter, and allows you to keep the degas (radiator fill tank) in its stock location.
The DCS Part #1943 positions the Brute Force air filter between the passenger side battery and the radiator. This is especially the kit to use if you are using a Ford 6.0 diesel radiator and a common rail style turbo.
This A/C manifold bolts to the back of a 1994 and newer Dodge A/C pump, making the A/C plumbing less of a challenge. All you will need to do is have some new hoses crimped between our manifold and your Ford pieces at the drier and evaporator.
SOME OTHER PARTS YOU WILL NEED TO GET ON YOUR OWN
Even if you buy everything Diesel Conversions® sells, you will need to come up with a few parts on your own, such as an exhaust down pipe (usually a Dodge down pipe can be a good start), and intercooler tubes (again Dodge stuff can be a good start). Automatic transmission equipped trucks will require a throttle position sensor. Depending on the year and what transmission your Cummins engine had on it originally, you may need to purchase a throttle position sensor, or look into other options. All 24-Valve engines already have a throttle position sensor that can be used for the transmission controller.
Sometimes customers buy engines out of industrial applications. These engines may not have the correct brackets for conversion friendly accessories.
CONSIDERING HAVING US DOING THE CONVERSION FOR YOU?
Give us a call and find out how Diesel Conversions® can do a professional conversion on your truck for a reasonable price. We have an international airport for travel from and back to our shop, and also can help with shipping options getting a disabled truck here.
NEW, REBUILT, OR USED ENGINES FOR SALE
This information is provided to you to help you make an informed decision on your conversion. If you have any questions do not hesitate to contact us.
*Diesel Conversions® is not affiliated with Cummins, Ford, or Dodge. Our use of these and other registered trademarks is for descriptive purposes only.
Diesel Conversion Specialists