Well you said electric motor oil. The motor itself has no oil. The gearbox has the oil.
And the oil in the gear box of an EV will degrade much the same as any gear box in a combustion vehicle.
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Oil change affect warranty?
- Thread starter bart_dood
- Start date
Well you said electric motor oil. The motor itself has no oil. The gearbox has the oil.
And the oil in the gear box of an EV will degrade much the same as any gear box in a combustion vehicle.
Very interesting. The Model 3 obviously has a different drive unit than the Model S, but even the Model 3 doesn't list a drive unit oil change on Tesla's website. I'd be very curious for someone who changes their Model S oil to send it for analysis. Heck, I'd even be willing to pay for the fees. 
Edit: So I found this video on YouTube, and the author mentions in a reply to some comments that they sent the oil in for analysis and it was "loaded with iron", with the exacts being "142PPM of iron. 7 times allowable numbers of 21PPM". This was on a 2012 Model S with the video posted in 2017. He also mentions "first service at 12,500 and every 50k thereafter", which was posted a year ago so I'm assuming that use to be the case but obviously not anymore (seeing as it's not listed on Tesla's service intervals). He apparently had another analysis done from a different car - I'm still trying to find the results.
Edit: So I found this video on YouTube, and the author mentions in a reply to some comments that they sent the oil in for analysis and it was "loaded with iron", with the exacts being "142PPM of iron. 7 times allowable numbers of 21PPM". This was on a 2012 Model S with the video posted in 2017. He also mentions "first service at 12,500 and every 50k thereafter", which was posted a year ago so I'm assuming that use to be the case but obviously not anymore (seeing as it's not listed on Tesla's service intervals). He apparently had another analysis done from a different car - I'm still trying to find the results.
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Here's the service manual instructions for replacing the oil on the drive units (if you don't have them already). I'm assuming the non P versions uses the small rear drive unit, but I've uploaded all three. The YouTube video I posted above is a P85, and surprisingly enough, the procedures are quite a bit different between the large and small rear drive unit. Anyways, would love to see some pictures and lessons learned when you get a chance to do this @bart_dood.
aerodyne
2 of 3 EV's - Defect Free!
Great stuff...I suppose someone spent $$$$ for the service manual.
They should make it free for all like the patents...
They should make it free for all like the patents...
Thanks for posting Shred, very useful. It does bring up some questions though, my understanding is the P Vs stock S drive motor on the RWD model S cars is the *same* (as is the battery) and the extra performance is simply software/firmware. Searching on ebay for Model S motors brings up the following, this is the motor from a Model S 70 RWD and its identical to the P version.
Searching ebay for a Tesla small rear motor brings up the other kind which seems to only be used on the AWD versions of the Model S. The other very strange thing in the oil change instructions for the smaller motor is the pulling of the drive shaft for filling. There is clearly a fill plug shown on the side of the casing yet it isn't used? The only reason I can think of is that Tesla realized later on via data/failures that the fill plug is too low and the oil level isn't where it needs to be. So they came up with this bandaid fix of pulling the driveshaft out and filling it there.
Looks like this gives an extra 1" of fill height, my guess is you could do the same thing by having the car at an angle, should be easy to calculate out what car angle is required to get this extra fill volume in.
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Here is the rear drive unit (small) used on D/AWD versions of the Model S. I have marked in blue where the proper fill plug is, the blue arrow is where Tesla wants you to fill it up to and the orange is the extra fill height you get from using the driveshaft hole.
aerodyne
2 of 3 EV's - Defect Free!
I bet there is a market for a product to simplify this small motor fill procedure. If the fill plug could be swapped for something with a one way valve or tap in it; then the correct volume of fluid could be pumped in then closed off. This would remove the need for this goofy procedure where the shaft has to be pulled on one side. Saving several hours of shop labor...
Maybe something like this would work?
Dorman EZ Drain Oil Pan Drain Plugs 092-006
aerodyne
2 of 3 EV's - Defect Free!
aerodyne
2 of 3 EV's - Defect Free!
Quick drain plugs very common on aircraft engines and very reliable. In this application would also allow for filling or sampling with a hose...search "safe air M12175 " for an example. Your drain plug threads may vary...
Yeah, I was considering doing this until I realized you have to pull the driveshaft out... I have access to a lift but still seems like a pain just to change the fluid. The front drive unit fluid change is interesting as well as you access it from the frunk, and you need a drain pain with a hose attachment.
I'm really curious to see more oil analysis done on higher mileage Tesla's. The only one I've seen is the one I posted above that was apparently "loaded with iron". It's worth noting that was an older Model S which my understanding is they made changes sometime in 2015 to fix a lot of the issues they were having before, but I'm not sure how much that would change the fact the fluid is still going to have contaminants. Not sure what the long term effects on the drive unit are with 4x the level of acceptable iron... can't imagine it's good. However, I'm guessing "good enough" that the probability of drive unit failure due to unchanged fluid before the 8 year warranty is up is so low that Tesla decided it's not economically worth changing.
Makes sense though if you plan on keeping the vehicle for a while (beyond the warranty) to change the fluid.
Does anyone know if Tesla will still change the drive unit fluid upon request? If so, how much do they charge?
I found some information on EV motors for vehicles and it made reference to oil cooling via a pump and spray bar on top of the rotor gives some advantages. This makes me wonder if Tesla found the small rear drive motor on the S was getting too hot with the oil level filled to the top drain plug and simply jammed more oil in to cool it. This isn't as much of a problem on the single RWD setup as the motor and gearbox is bigger and can handle the thermal load better?
It also might explain the model 3 rear drive unit; they perhaps found they could run a smaller motor (smaller and cheaper) harder by adding a pump to suck the oil through the spin on filter (therefore getting cleaner oil and longer life) and pumping it over the rotor thereby cooling it. So getting the lower cost and weight of a smaller motor, but pretty much the same performance as a larger heavier motor.
It also might explain the model 3 rear drive unit; they perhaps found they could run a smaller motor (smaller and cheaper) harder by adding a pump to suck the oil through the spin on filter (therefore getting cleaner oil and longer life) and pumping it over the rotor thereby cooling it. So getting the lower cost and weight of a smaller motor, but pretty much the same performance as a larger heavier motor.
Got it finished! got out of work early today and had enough time to get this done.
So here goes my oil change writeup....
I used ramps (with chocks), offset to compensate slightly for my driveway which slopes in 2 directions. The car was just about level when all done.
Next are the under panel retain bolts, these are almost all 10mm Hex heads, there are two plastic mushroom expanding bolts. You have to remove the two aerodynamic things that sandwich along the length. Make a note of what types go where, as there are 2 kinds of 10mm bolts, some are threaded (M4?) and some are self tapping and pointed. Don't mix up the locations of these.
So here goes my oil change writeup....
I used ramps (with chocks), offset to compensate slightly for my driveway which slopes in 2 directions. The car was just about level when all done.
Next are the under panel retain bolts, these are almost all 10mm Hex heads, there are two plastic mushroom expanding bolts. You have to remove the two aerodynamic things that sandwich along the length. Make a note of what types go where, as there are 2 kinds of 10mm bolts, some are threaded (M4?) and some are self tapping and pointed. Don't mix up the locations of these.
10 pic max per reply..
I checked the temp of the transmission, this is after about 30 mins resting after a drive. It gets warm but not hot, the two drain plugs are both 8mm Hex, always remove the fill plug *before* the drain plug!
I checked the temp of the transmission, this is after about 30 mins resting after a drive. It gets warm but not hot, the two drain plugs are both 8mm Hex, always remove the fill plug *before* the drain plug!
The fill plug is also magnet and showed some ferrous spooge on it which seems normal. NOTE: when I removed the fill plug I got a little ATF fluid coming out, so it was filled up to the plug. See my later reply about this:
The drain plug at the bottom had more ferrous spooge, but nothing I'm concerned about:
The drain plug at the bottom had more ferrous spooge, but nothing I'm concerned about:
Here is the old fluid, I used a clean smaller container to catch it in:
I used a pump to pump in the new fluid, this is the pump *after* I used it. I pumped ATF through it to waste to prime it first and make sure there we no plastic particles in the pump or tubing which could end up in my motor, I filled with Valvoline maxlife synthetic Dexron VI:
I used a pump to pump in the new fluid, this is the pump *after* I used it. I pumped ATF through it to waste to prime it first and make sure there we no plastic particles in the pump or tubing which could end up in my motor, I filled with Valvoline maxlife synthetic Dexron VI:
This bit is interesting. The Tesla manual calls for 1.5 quarts of fluid for a fill. However when I undid the fill plug some drained out, so it was filled to the plug.
When I was pumping in clean fluid (not shown, as hard to hold a phone and do the fill at the same time) it took more fluid to get it up to the fill plug, I estimate somewhere around 1.8-1.9 quarts (I lost a little). I cleared out the rest of the new fluid from the ATF container and poured the old fluid in to keep it. Note the level, its almost at 2 quarts (again I lost some on the transfer).
So it seems Tesla does *not put in 1.5 quarts* in its big motors, they just fill to the fill plug which equals about 1.8-1.9 quarts.
When I was pumping in clean fluid (not shown, as hard to hold a phone and do the fill at the same time) it took more fluid to get it up to the fill plug, I estimate somewhere around 1.8-1.9 quarts (I lost a little). I cleared out the rest of the new fluid from the ATF container and poured the old fluid in to keep it. Note the level, its almost at 2 quarts (again I lost some on the transfer).
So it seems Tesla does *not put in 1.5 quarts* in its big motors, they just fill to the fill plug which equals about 1.8-1.9 quarts.
The rest is just buttoning up to put everything back. Plugs are tightened to 28nm torque which is on the high side so *do not* torque any higher! the seal is an O-ring in shear sealing so tightening more does not seal any better.
Make sure you clean up excess oil, put all the fasteners back in the right place. I drove them down loosely with an automatic screwdriver then torqued them by hand to ensure correct tightness.
I did a test drive later, I swear the motor is now quieter than it was before the new fluid. Might be my imagination.
The old fluid wasn't too bad, a bit dark, no metallic sheen that I could see. There were some tiny chunks in the fluid at the bottom of the container but nothing to worry about. I'd say a 40k mile interval would be fine on this motor assuming you want to keep it in very good shape. I'll be doing by next one at 160k miles in about 2 years!
Next I have to do some clear bra and perhaps a brake fluid flush. Oh and I found some odd things which I will post in a different thread.
Make sure you clean up excess oil, put all the fasteners back in the right place. I drove them down loosely with an automatic screwdriver then torqued them by hand to ensure correct tightness.
I did a test drive later, I swear the motor is now quieter than it was before the new fluid. Might be my imagination.
The old fluid wasn't too bad, a bit dark, no metallic sheen that I could see. There were some tiny chunks in the fluid at the bottom of the container but nothing to worry about. I'd say a 40k mile interval would be fine on this motor assuming you want to keep it in very good shape. I'll be doing by next one at 160k miles in about 2 years!
Next I have to do some clear bra and perhaps a brake fluid flush. Oh and I found some odd things which I will post in a different thread.
FlatSix911
Porsche 918 Hybrid
Well done writeup! I have also used Blackstone on my Porsches with excellent results
Blackstone Laboratories – Oil Analysis – Learn What's Going On In Your Engine
Blackstone Laboratories – Oil Analysis – Learn What's Going On In Your Engine
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