Possible Battery Issue?

[Viro]

I've got a 2018 75D that gets 246 fully charged. I've made a few trips to the Indianapolis Tesla service shop to get minor repairs done and noted it was using 206-214 miles worth of energy to travel 138 physical distance. This occurred with temperatures in the high 60's and is pretty much the same with temperatures in the 20's-30's. I asked Tesla and they didn't seem concerned.

Today I had to go back to the service center for more work and I left my car so I received a loaner. The loaner is a 2016 MS 85D with 246 miles of charge (100% charge) and 58k miles on it (I have 25k miles on my car). When I drove it home, it was registering I used 152 miles of the 138 physical miles traveled. I drove the exact same route with the same interior heating conditions at the same speed (63 mph all highway) and with same weather conditions (wind 5-10 mph out of the W/NW( I was traveling N & S).

When I called the Tesla Service Center and asked why there is such a difference between the two cars they said it'd not apples to apples comparison due to the hardware configuration. But if they have the same battery wouldn't it be?

I'm just trying to figure out if this is something I need to pursue with Tesla. It seems odd to me that I am using 200+ miles worth of power to travel 138 miles in my car but only 152 in the loaner car.. Maybe if I had a long range version it wouldn't be that big of a deal but when you only have a max range of 246 miles to begin with, loosing 50 miles is kinda a big deal.

This is my first electric car, am I just being too picky expecting too much? I don't want to hassle Tesla if this is just the way it is.

Any input would be appreciated.

 

[Rocky_H]

When I called the Tesla Service Center and asked why there is such a difference between the two cars they said it'd not apples to apples comparison due to the hardware configuration. But if they have the same battery wouldn't it be?

Well, you're proposing a hypothetical that isn't true.

I've got a 2018 75D [...] The loaner is a 2016 MS 85D

The 75 battery is a 350V one with fewer cells than the 85 battery, which is a 400V type with more cells (and more weight).

Which actually brings up an interesting strange question. The smaller battery versions, being lighter, usually have a little better efficiency. The tech is technically correct that it's not quite apples to apples, but it is going the wrong direction. Your 75D should be a bit more efficient and use fewer rated miles than the 85D.

So that is odd. But there could be other issues involved. Tire size/quality/wear/pressure and wheel alignment can have pretty significant differences in the efficiency levels of different cars.