I know this is an old thread but I'm looking to do the same thing for my '17 EL XLT with fixed running boards. These aren't wide enough for my big feet and they tend to be slippery (and I'm at the age now where one good fall and that's all she wrote). We also have an '18 with power running boards. They are wider, not slippery, and at a lower height making them more comfortable to use. As a side benefit, I think the '15-17 truck looks better without the fixed running boards IMHO.
What I've learned so far is the OEM boards are made by AMP Research for Ford. But, they won't sell them for our trucks -- they only make aftermarket packages for the F-150, etc. I don't know about "shorty" models, but steps made for the F-150 are not long enough to fit extended wheelbase Expedition and Navigator trucks. To get a perfect fit, we need OEM parts from Ford.
The package consists of the following components:
- LH step with end caps (81 inches long for "shorty" models, 92.25 inches long for Expedition EL and Navigator "L" models)
- RH step with end caps
- LH front bracket with motor
- RH front bracket with motor
- LH rear bracket
- RH rear bracket
- Connecting torque rods (one per side, extended wheelbase models only)
- Control module (with 2 connectors)
- Wire harness (one plug per motor, 2 plugs for the module)
The steps are one piece with separate plastic front and rear end caps. The bottom of each step is matte black while the outward-facing portion of the step is painted to match the vehicle.
Extended wheelbase models use a different part number for the brackets. There is one extra long hinge pin in each bracket that sticks out and secures to a torque rod that connects the front and rear brackets. Shorty models don't have this connecting rod.
I don't see any reason why you could not use EL brackets in a "shorty" as long as you are not installing the connecting torque rod. Or, I suppose you could cut the torque rod to length and then use it in a shorty model. Unless I am missing something, this should work -- at least in theory.
2007-14 models either have a different motor altogether or they use a motor that has a different connector plug. For whatever reason, the plug was changed in 2015. It could be that Ford switched suppliers and started using a different motor, who knows.
Ford supplies replacement motors complete with bracket and they are PRICEY. As I am typing this, the 2015-17 RH front bracket with motor lists for about $800 while the LH motor is nearly $1300. That's typical price gouging as they know the LH motor is most likely to fail due to higher use.
Aftermarket replacement brackets can be had for far less but this might be a situation where you get what you pay for. I have no idea of the quality of a non-OEM bracket assemblies.
The brackets are cast aluminum with 3/8" DIA stainless pins and PTFE-coated press-in bushings. Over time the bushings fail when the PTFE coating wears through. At that point, the bushings need to be replaced but this is labor intensive and requires a heavy-duty press. I haven't seen anyone offering a rebuild service for these brackets.
When adding options to their vehicle a lot of people go to the expense of buying an entire wire harness. I don't recommend doing this as new harnesses from Ford are very expensive and many wrecking yards won't bother to extract a wire harness from a salvage vehicle because it can be labor intensive. What you really need is the connector for each motor along with a couple feet of harness that includes the grommet where the harness passes through a hole in the body. In addition, you also need the two connectors for the control module. With those in hand, it should not be too difficult to wire everything up.
Of course, getting it wired is not the entire story. You also need to do some programming in FORScan to add the Power Running Board Module to the truck and get it working. I haven't seen any info yet on exactly how to do that.
As an alternative, AMP Research makes a controller and harness (with override switch) that connects to the OBDII port and controls their aftermarket steps. You could use this controller in place of the Ford module, but you would not have any settings in the instrument cluster (at least for 2015-17 models).
If anyone reading this can add to this information, please let me know! Also, let me know if I have gotten anything wrong. I am still researching and trying to learn as much as I can about these power running boards in hopes I can successfully add them to my truck.
Thanks for your help!