21st Century Truck
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Folks,
For general information, a good EV tech I had known for years just diagnosed a failing bearing in the front drive unit.
Symptoms: this past Sunday while driving on cruise control at a speed of about 65 mph on a limited access highway I heard a new constant low-volume sound that reflected off the concrete center highway divider. The sound was a low-level thrumming, and only present when the motors were not under load. When I applied the gas pedal, the low level thrumming disappeared. When I (or the cruise control) let off the gas, the low level thrumming reappeared and stayed constant. The thrumming was definitely on the front left side of the truck.
On further testing, the low level thrumming would manifest at and above speeds of about 12 mph. It would grow with increased speed until it plateaued into a constant noticeable although not overwhelming background level, at about above 25 mph. There was some slight, constant gas pedal vibration as well, although far less noticeable.
Today, after some thorough shop testing and road testing, the diagnosis is: a bearing inside the front drive unit which is beginning to fail. The truck is evaluated as "driveable, but..."
Of course (sigh...) my truck is 12,647 miles beyond the Ford extended EV warranty.
The practical choices are two:
- drain the traction battery [edit:] coolant, remove the offending front drive unit (i.e. the front electric motor), disassemble the electric motor, remove and replace the failing bearing, reassemble everything.
- or drain the traction battery [edit:] coolant, remove the offending front motor, replace the entire front motor, reassemble everything.
We are awaiting the status of available front motors before I and the shop make action decisions. Apart from checking the supply of same, the shop estimates that, based on labor costs and the necessary replacement of other electric motor components like single-use stretch bolts etc., the overall price of a bearing replacement vice a full motor replacement would likely be close to a wash.
Assuming I will authorize one or the other (I'm leaning on a full motor replacement right now) I will also request a drain & refill of the rear electric motor's Mercon fluid, as the indicated drain & fill interval is at 140 thousand miles or about 26 thousand miles away now, and since the overall labor to drain & fill the electric motors closely resembles the labor to pull and fix the front motor anyway i.e. drain the traction battery, remove the battery armor plates, etc. etc. This way, both motors would have their drain & fill maintenance mileage reset together.
FYI - the price seems to be around $11 thousand - salty but better than the price of a new car. We've driven the truck far, wide and sometimes, pretty hard hehe.
I am posting this info here for general awareness... maybe it'll be helpful to others.
For general information, a good EV tech I had known for years just diagnosed a failing bearing in the front drive unit.
Symptoms: this past Sunday while driving on cruise control at a speed of about 65 mph on a limited access highway I heard a new constant low-volume sound that reflected off the concrete center highway divider. The sound was a low-level thrumming, and only present when the motors were not under load. When I applied the gas pedal, the low level thrumming disappeared. When I (or the cruise control) let off the gas, the low level thrumming reappeared and stayed constant. The thrumming was definitely on the front left side of the truck.
On further testing, the low level thrumming would manifest at and above speeds of about 12 mph. It would grow with increased speed until it plateaued into a constant noticeable although not overwhelming background level, at about above 25 mph. There was some slight, constant gas pedal vibration as well, although far less noticeable.
Today, after some thorough shop testing and road testing, the diagnosis is: a bearing inside the front drive unit which is beginning to fail. The truck is evaluated as "driveable, but..."
Of course (sigh...) my truck is 12,647 miles beyond the Ford extended EV warranty.
The practical choices are two:
- drain the traction battery [edit:] coolant, remove the offending front drive unit (i.e. the front electric motor), disassemble the electric motor, remove and replace the failing bearing, reassemble everything.
- or drain the traction battery [edit:] coolant, remove the offending front motor, replace the entire front motor, reassemble everything.
We are awaiting the status of available front motors before I and the shop make action decisions. Apart from checking the supply of same, the shop estimates that, based on labor costs and the necessary replacement of other electric motor components like single-use stretch bolts etc., the overall price of a bearing replacement vice a full motor replacement would likely be close to a wash.
Assuming I will authorize one or the other (I'm leaning on a full motor replacement right now) I will also request a drain & refill of the rear electric motor's Mercon fluid, as the indicated drain & fill interval is at 140 thousand miles or about 26 thousand miles away now, and since the overall labor to drain & fill the electric motors closely resembles the labor to pull and fix the front motor anyway i.e. drain the traction battery, remove the battery armor plates, etc. etc. This way, both motors would have their drain & fill maintenance mileage reset together.
FYI - the price seems to be around $11 thousand - salty but better than the price of a new car. We've driven the truck far, wide and sometimes, pretty hard hehe.
I am posting this info here for general awareness... maybe it'll be helpful to others.
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