May of this year I was driving our '21 CA Rte 1 back from western North Carolina on a Sunday, when in South Carolina I received the 'Powertrain Malfunction service vehicle soon' message followed by a yellow wrench on the drivers display. The Mach E seemed okay, and being that Ford dealerships and service departments would all be closed, I kept driving. At the next stop I read the Ford Pass message and it indicated that power would be limited. A few times when I stopped to charge, the message did not reappear, but most of the time it did. I made it back to Florida with no problem except for the recurrence of the message. That week I called the local Ford dealership nearest to us and a service tech answered. I explained what happened and he said he would talk to his manager and they would call me back. This BTW is the same dealer that a few months before had put off our request for a second key fob after taking the vehicle in for that purpose only to discover they were on back-order. After waiting a few days, and no return call, I called Coconut Point Ford in Estero and the service advisor scheduled a diagnostic appointment three weeks out, which was one day before we planned to leave to drive to Iowa. Rather than fly, or rent another EV, I found a '21 Select at Englewood Ford that matched up with what we were looking for. We bought the Select, dropped the CA Rte 1 off on the appointed day, and left for Iowa as planned. However, we were driving the Select with the standard range battery instead of the CA Rte 1 with the extended range battery. As my wife and I were on the way to Iowa I heard from the service rep that the electric auxiliary oil pump needed to be replaced and it would be major work. Also that it would be another month or two to schedule that work. While they had the CA Rte 1 we asked if they would check the drivers side taillight (which was loose), as well as get us a second key fob, and address any other updates and recalls. Today (August 16) we received the CA Rte 1 back from Coconut Point Ford. We got our second key fob. The modules needed two different updates for Bluecruise. The car drove well on the way home. Fortunately, the oil pump was covered by the powertrain warranty. However, the taillight bracket replacement was not covered due to the Mach E being over 36k miles, and out of the bumper-to-bumper warranty. Our total cost was under $100.
Yes the electric motor and transmission uses Ford MERCON ULV transmission fluid for cooling. The oil pan and pump is unfortunately located within the entire motor and transmission housing and significant disassembly is required. You can see the Mexican assembled front Mach-E Eluminator motor (underside) specifying in Chinese 油冷 or OIL COOLING.
This Mustang Mach-E GT Motor Details is a really good disassembly video by Professor John Kelly at Weber State. The first few minutes of the video show the oil pump and use of the same transmission fluid as ICE Fords While my Mach E is not a GT, in the video he says the rear motor assembly is very similar for all Mach E's. Also, the screenshot above by @teslarati97 can be seen at 4:40 of the video.
I'm glad to learn it's coolant and not lubricant oil that needs pumping. Professor John Kelly is a national treasure.