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EV motor maintenance? Gear fluid change? When?

PreservedSwine

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Over 600 page owners manual, and the closest thing I can find is changing the "transmission fluid" at 160k. Since we don't actually have transmissions, are we to assume this is the ev motor gear fluid?

Other than flushing the brake and cooling system fluid periodically, are we supposed to change the ev motor fluid occasionally as well? I'm assuming letting the ev motor fluid go unchanged for too long would ruin the motor, but I really don't have anything to base this on.

Any input appreciated.
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21st Century Truck

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I had this very thing go BLOOOEY on my old Mach E Mustang, when the fluid in the front motor leaked internally through the motor seals. The techs showed me the orange motor connector when they took that motor out under warranty, and the fluid was visibly oozing through the orange connector's pins.

Per the techs' discussion with Ford Corporate and with me later, the fluid is the usual Motorcraft Mercon transmission fluid, and its function is to both cool and to lubricate the big electric motors. Some of the motors' internal parts are lubricated while other internal parts are dry... hence the internal seals.

I assume the Lightnings' electric motors use the same or very similar technology.

BTW -when, still under warranty but toward the end of the warranty as it was affected by the motor changeout (12 months's warranty for a major new part like that) the front motor had to be changed out once again i.e. 3 front motors in 75 thousand miles / 26 months of ownership, I traded that Mach E in for the current Lightning. I figured "let's make this hard-driven Mustang the next guy's problem" despite the depreciation.
 

RLXXI

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According to the owners manual, 150,000 miles change the oil in the transmission, other than that it's just look at stuff, rotate the tires, replace the cabin filter every so often.
 

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Henry Ford

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You can review the maintenance schedule in the Ford app as well.
 

Jseis

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On a Lightning tear down (Munro), I recall he “estimated“ final drive transmission ratio from the electric motor at 7:1 and max motor rpm at 14,000.

Given the lack of ICE engine heat/waste heat , a gear drive oil change at 160K seems reasonable.
 

RLXXI

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On a Lightning tear down (Munro), I recall he “estimated“ final drive transmission ratio from the electric motor at 7:1 and max motor rpm at 14,000.

Given the lack of ICE engine heat/waste heat , a gear drive oil change at 160K seems reasonable.
Exactly.
 

WXman

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On a Lightning tear down (Munro), I recall he “estimated“ final drive transmission ratio from the electric motor at 7:1 and max motor rpm at 14,000.

Given the lack of ICE engine heat/waste heat , a gear drive oil change at 160K seems reasonable.
All the published specs show it at 9.61:1. But I'm not sure I follow you on the heat thing. What does engine heat have to do with axle gear temperature? I would venture to say that the electric motor gear oil will get hotter than the differential on an ICE because the case is also housing the motor, whereas on an ICE truck the differential is separate, and it catches a lot of airflow.
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