Greaseless ball bearings:Tesla should use these instead ?!

[fromport]

While the ball bearing might be among Leonardo Da Vinci's less celebrated inventions, it's arguably one of his most important.
Coo Space claims the ADB experiences as little as 10 percent of the friction of a regular ball bearing

http://www.gizmag.com/greaseless-ball-bearings-coo-space-adb/37689/

Throw out the Ceramic that cause the problems...

 

[smoothoperator]

has anyone confirmed that it is indeed the bearings? I am in the process of replacing the steel bearings currently on another EV (not a tesla variant) with hybrid ceramic bearings. Would be interesting to know if this will introduce the hum. Due to the design of the tesla motor (conductive path through the shafts) I believe it is required for them to use non-conductive ceramic bearings. The vehicle that I am doing a replacement on, I believe, has issues with the bearings being used as a ground path- which is causing some strange issues. Could the noise be more due to gear-whine? I have read the other thread on here about the replacements and it seems like Tesla/Toyota has not root caused this issue as yet?

 

[qwk]

has anyone confirmed that it is indeed the bearings? I am in the process of replacing the steel bearings currently on another EV (not a tesla variant) with hybrid ceramic bearings. Would be interesting to know if this will introduce the hum. Due to the design of the tesla motor (conductive path through the shafts) I believe it is required for them to use non-conductive ceramic bearings. The vehicle that I am doing a replacement on, I believe, has issues with the bearings being used as a ground path- which is causing some strange issues. Could the noise be more due to gear-whine? I have read the other thread on here about the replacements and it seems like Tesla/Toyota has not root caused this issue as yet?

The Tesla drive unit can have many different noises. Most of them are either inverter or gearbox related. I'm not sure I have heard of any motor bearing issues. I'll try and find out.

 

[fromport]

The Tesla drive unit can have many different noises. Most of them are either inverter or gearbox related. I'm not sure I have heard of any motor bearing issues. I'll try and find out.

within 500 miles after replacing the drive train, my 2696 starts to make a very low noise at speeds 54mph and up. My wife says it is like a big fly is humming under the hood. When you go up a hill ( or under regenerative braking so under load) into a corner at those speeds and leave the "mid position" of your steering wheel, you actually feel a vibration in the steering wheel.

Is that a known phenomena ?

 

[qwk]

The Tesla drive unit can have many different noises. Most of them are either inverter or gearbox related. I'm not sure I have heard of any motor bearing issues. I'll try and find out.

within 500 miles after replacing the drive train, my 2696 starts to make a very low noise at speeds 54mph and up. My wife says it is like a big fly is humming under the hood. When you go up a hill ( or under regenerative braking so under load) into a corner at those speeds and leave the "mid position" of your steering wheel, you actually feel a vibration in the steering wheel.

Is that a known phenomena ?

Yes, that sounds like the "drone" issue. The 2nd gen Tesla drive units have a much better chance to be quiet. It's a different part#, and I don't think that Tesla sends those out for Rav replacements. Tesla remanufactured units(what the Rav gets), suck in quality. That's why you and many Model S owners that have had a DU replacement are having noise issues. What is the vin on your DU(sticker on bottom of motor)?

 

[fromport]

Yes, that sounds like the "drone" issue. The 2nd gen Tesla drive units have a much better chance to be quiet. It's a different part#, and I don't think that Tesla sends those out for Rav replacements. Tesla remanufactured units(what the Rav gets), suck in quality. That's why you and many Model S owners that have had a DU replacement are having noise issues. What is the vin on your DU(sticker on bottom of motor)?

Thanks for all the info!
I will look when i get back home.
Doing a road trip through Oregon at the moment.
have to remove a shield in order to see the number.
will report in a week or so ;-)