i3 Motor/gearbox failure... help!

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This problem is on the rise as these cars reach higher mileage.

My 2015 BEV (Tera, w/every option) started this motor bearing whine at about 94k miles. The dealership (BMW South Kansas City) tried to get me to trade it in for $2500... what an insult.

They estimated over $16k for the repair, trying to convince me it was EME (Inverter), Gearbox, and Electric Motor.

There's a lot of owners out in public forums and Facebook Groups that have had this happen, outside of warranty, and with enough coaxing - get Goodwill replacement of the motor (parts only, customer pays labor)

I'll be pushing at BMW NA pretty hard... I just do not accept that this $50K car wasn't designed to last longer than 90k miles before suffering a terminal failure that costs more than the current used market price of the car to fix.

BMW changed the motor front bearing design from a normal roller bearing to a tapered roller bearing in 2018, which fixed the "no load - self destruct" problem with normal cylindrical roller bearings. When a roller bearing already has race wear, and is then run with little-or-no lateral load, the rollers can stop spinning. Then when lateral load is applied (motor torque jumps up), the 'non-rotating' rollers will skim along the inner surface of the outer race, WIPING any oil film away... then the next roller is rubbing metal-to-metal, causing serious wear.

This condition won't happen in a tapered roller bearing, since they require some pre-load to keep the rollers seated. BMW knew this years ago, but only fixed it in the 2018 model year.... the same year they increased the power output for the "S" model.

This new BMW part number immediately became the Service Replacement Part for all years of the i3 that had a bearing failure... so they won't get repeat failures and have to do it over again.

It is a known design flaw... but they won't admit it until it becomes a Class Action legal matter.... if even then.

edit: One of the outstanding design flaws they made was choosing cheap "sealed" bearings for a over-billion-cycle electric motor - that spins over 11,000 RPM, in all kinds of climate environments.
 
Arm said:
My take is if anyone plans to keep this car long term, put aside a couple of hundred dollars a month aside for future repairs, tires, etc. That's what I'm doing. I know eventually my 2018 BEV will need work...but until then, I'm building a nest egg for it. And if I don't use it, even better.

Kind of defeats the goal of buying an EV to save money that we were spending on gas (petrol).
 
ronbot said:
Arm said:
My take is if anyone plans to keep this car long term, put aside a couple of hundred dollars a month aside for future repairs, tires, etc. That's what I'm doing. I know eventually my 2018 BEV will need work...but until then, I'm building a nest egg for it. And if I don't use it, even better.

Kind of defeats the goal of buying an EV to save money that we were spending on gas (petrol).

What goal are you referring to? Saving money?
 
Can you fit a complete motor and gear box assembly from a 2018+ i3 into my 2015 i3? If I am chasing the bearing issue, probably should swap in a new transaxle too. I’d rather invest more into this car than buy newer one. The rest of the car is holding up well at 95k miles.
 
Vagabond63 said:
Can you fit a complete motor and gear box assembly from a 2018+ i3 into my 2015 i3? If I am chasing the bearing issue, probably should swap in a new transaxle too. I’d rather invest more into this car than buy newer one. The rest of the car is holding up well at 95k miles.

I'll soon be finding out, that's what I bought for my replacement... 2018 complete electric drive assembly, 24k miles, with EME... from a Rex S, but that doesn't change anything about the electric drive motor.
 
I await news of your replacing with a 2018 motor. Are you doing it yourself or have a place?

Update: I bought a salvaged 2018 motor and gear box unit. I’ll soon have it. From what I see it will fit just the same. The only difference are tapered roller bearings on the out put shaft. I’ll report back soon.

Where can you get a proper manual for tear downs?
 
If you join the BMW i3 Worldwide facebook group you can download a bunch of manuals. they are under "file" tab.
 
I’m doing lots of reading with a view to possibly buying an i3 BEV. Is this thread suggesting that a post 2018 i3 would have a much lower chance of getting the motor bearing issue? I was contemplating a 2020 or 2021 car as the newest I could afford but am concerned about BMW repair costs. I'm not on Facebook.
Paul
 
I’m doing lots of reading with a view to possibly buying an i3 BEV. Is this thread suggesting that a post 2018 i3 would have a much lower chance of getting the motor bearing issue? I was contemplating a 2020 or 2021 car as the newest I could afford but am concerned about BMW repair costs.
Yes, starting with the 2018 model, the motor bearings were apparently updated to tapered roller bearings that should handle the motor's torque better and thus have a longer life.
 
My 2016 motor was making a grinding noise . BMW technician told me sell it as it was just out of warranty and would fail in a few years. Failed in 4 weeks. No relief from BMW Canada and was quoted $8000cad for motor and about $5000 to install. Sourced a salvaged 2018 motor for $2400 and paid $2400 to private mechanic to install. Been 6 months and no issues.
 
My 2016 motor was making a grinding noise . BMW technician told me sell it as it was just out of warranty and would fail in a few years. Failed in 4 weeks. No relief from BMW Canada and was quoted $8000cad for motor and about $5000 to install. Sourced a salvaged 2018 motor for $2400 and paid $2400 to private mechanic to install. Been 6 months and no issues.
Hopefully they also entered the "Offset" value into the drive system...? That tells the EME what the exact offset is from the rotor to the magnetic position sensor, aka "resolver". Without performing this data entry, the EME will still use the previous motor timing value, and your new motor will be less efficient, and possibly run very hot.
 
I got my car back on the road after an 11 month hiatus... while waiting for money and parts.

I found a 2018 drive motor/transmission on ebay from a Rex, so I knew the transmission would not be compatible... but it was a great deal... had under 100 miles. It was a legal scrap, a test vehicle that was never registered... and not damaged.

I also bought a BEV transmission with zero miles. Seller bought it online from a BMW parts dealer, but chose the wrong one for his Rex.

I also bought all new mounts and brackets to bring it all up to date for the 2018+ motor.

So yes, all motors are interchangeable, and yes... the 2018 revised motor is now the required p/n for repair of all model year i3.

Used an independent BMW specialist shop, they were able to code-in the new Offset value with their aftermarket diagnostics system.

Back on the road again, absolutely silent drive system.

Planning on trying the 94Ah upgrade this Summer... and replace the aircon compressor at the same time... "preventative maintenance "... since it's still running quiet.

Still looking for detailed info on how to perform the battery upgrade coding. I know the early model years were "94Ah aware", and supposedly it's a relatively simple "retrofit"... I just have not had success finding this information.

My 94Ah battery is from a salvage car that was rather lightly rear-ended, but had NO airbag deployments... so the hope is that it has not been "locked" from the accident.
 
Can you fit a complete motor and gear box assembly from a 2018+ i3 into my 2015 i3? If I am chasing the bearing issue, probably should swap in a new transaxle too. I’d rather invest more into this car than buy newer one. The rest of the car is holding up well at 95k miles.
Yes... I did.
 

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