I have two Tesla's; a MS and a Model X. Both are 75d and both were built in 2016.
At my home charger the Model S charges at 3 miles per hour faster than the model X. I get 28 miles per hour charge with the X and 31 miles per hour with the S. Is that normal and should be expected or is that an anomaly?
There isn't enough information to make a determination as a number of factors could affect this.
1) Were both batteries at the same state of charge when you started?
As an example, when drained low the car takes a bit to ramp up in charging.
2) How are you wired? Are your two chargers wired to talk to each other?
If using a v2 charger and wired together, the chargers will prioritize the car with the lowest SoC.
3) Did both cars start charging at the same time?
If it's cold outside, the car takes a bit to ramp up charging as well. If one car is warmed and the other is cold, there could be a discrepancy.
As someone else said, take a look at kw and not mi/hr.
A 10% SoC on a MX75D = 23.7mi
A 10% SoC on a MS75D = 24.9mi
So assuming they both charge at the same rate you would see different mileage differences.
I ran this test on both my cars - both were 60Ds at the time; MX & MS. I initially thought the same until I realized the kw rate was the same. I tested this at home as well as on the supercharger. The only time I did actually see a difference was during items 1-3 above.
