After a brand new drive unit install yesterday (not remanufactured), new battery contactors, and an update to v .251, I am concerned that something may be wrong with energy usage or range calculations. I have a 190 mile round trip today (no dest charger) so I only charged to 90%. I decided just to "drive slow". Previously on long trips I observed that if you drive slower, the rated range doesn't drop as fast (common sense if your going 250Wh/mi vs 350Wh/mi). I'm at my destination halfway and the rated range seemed to drop much faster than they should have given how slow I was driving and how little energy I used. Rated range at start: 222 Rated range after 94.6 miles: 130 Display: Total energy used: 21.1kWh Avg energy: 223Wh/mi Now the problem for me is that those numbers do not make sense. They do not look accurate. By my calculations, since I drove so conservatively and used little kWh, my range should have only dropped by about 70 miles. Instead it dropped by 92. AFAIK Tesla's rated range calculation is done assuming about 300Wh/mi. Since I only went 223Wh/mi, that means I saved about 77Wh/mi by driving conservatively. Over 94.6 miles that is 7284Wh of savings. Using 300Wh/mi , that means I should have saved about 24.2 miles, effectively meaning that rated range should have only dropped by about 70.3 miles. Instead it dropped by 92 miles. IMO that's a pretty significant error difference. You can do this calculation several ways. I'll do it another way. If I only used 21.1kW, at the rated range calculation of 300Wh/mi, it should have only dropped 70.33 miles, not 92 miles. Again, assuming Tesla's rated range calculation uses 300Wh/mi, common sense says if I drove 94.6 miles at an average of 300Wh/mile the rated range should drop by about 94.6 miles (duh). It dropped by 92 miles. Very close. However , 223Wh/mi is a significant difference from 300Wh/mi. About a 25.6% difference. I should have got about 74.3% of what 300Wh/mo would have got. The difference between 92 and 94.6 is not 25.6%. Guess what 74.3% of 94.6 is? 70.3. Am I calculating this wrong or does something look off to you all too?