This is a "heads-up" informative listing, in which I wanted to share my experience of replacing the left front door window regulator and motor assembly. The original Ford window regulator/motor had stopped working, and so I purchased a Dorman window regulator assembly, complete with motor, listed as a replacement for the OEM Ford parts. Installed the Dorman assembly, per instructions found on-line, and after consulting with my local Ford dealer. The installation process involves drilling out existing rivets, and installing new short screws/nuts in place of the factory rivets. Some of the screws are very close tolerance to inside moving parts of regulator, and therefore must be installed with the head on inside of door, nut on exterior face of door panel, to provide adequate clearance Completed the installation, then reconnected all wires, and tested window operation, and although the up-down operation worked OK, the auto-down feature did not work. When auto-down was engaged by pushing the switch all the way down and then releasing, the window would move only a few inches down, then stop. This was very strange, and led me to test the switch, which I did with a Fluke multimeter instrument, and found that the Ford OEM switch was fine, and I confirmed that by substituting a new switch, with same operational results. Because I had planned to have brakes checked at Ford, I asked them to give me the vehicle's trouble code, and they did so, which said a delay relay was not operating correctly. I checked the relay, and it was OK, so the problem was in the circuit beyond the relay, and so I began to suspect the motor, especially after a Ford tech at the dealer demonstrated that with more physical resistance (friction, load) applied to the window to cause the motor to work harder, the window would go down without stopping in the auto-down mode. At that point I called Dorman, and spoke with one of their technical folks who was very helpful. I asked him to give me the electrical characteristics of the Dorman motor, and he did so, along with the same information on the Ford OEM motor. The Dorman motor would draw about 3.0 amps, and the Ford motor draws about 7.5 amps. Because the auto-down mode is controlled by the computer, and relies on a current sensing circuit, I have concluded that the difference in the current draw, 3 amps vs. 7.5 amps is the cause of the malfunction of the auto-down mode. Dorman agreed with me, and has reimbursed me for the expense of their partially functioning window regulator/motor assembly. There are now 2 possible fixes 1) Replace the motor with a Ford Motorcraft part, or add resistance in the motor's power feed circuit so that the car's computer sees more amperage draw. I hope this will be helpful to someone dealing with this same problem. This might also effect other model years, because the 1999 Expedition is similar to model years 1997 thru 2002.