Considerations buying a 2nd hand Long Range Model 3

[S Ramsay]

Hi,

I've found a 2020 model 3 long range at a good price, but maybe the price is good for a reason. Its got 90k miles on the clock and the screenshot from the dealer of its charging status is that it is between 27% and 28% charged with 75 miles remaining. This would give a nominal range of 272 miles. I believe that this variant would have had 348 miles nominal range when new, so 21-22% degradation assuming that the battery is calibrated correctly. Its got 30k miles and 4 years left on the warranty, I anticipate doing about 8k miles a year, so if completely fails then I am still within the warranty for a bit. 272 miles nominal is is still better than the nominal range for the standard range models from when they were new going for the same price which makes it seem like a decent buy. Would this be ringing alarm bells for you or if treated well you would imagine it retaining its current nominal range for a while? And if the bulk of my driving was going at 65 mph on the motorway, how different would you expect the nominal and real range to be? Or any other thoughts or considerations for buying a used car such as this?

Thanks

 

[LoudMusic]

That seems like excessive degradation on the battery, but what do I know ...

I bought a 2019 M3 standard range used and was displeased to discover it didn't come with auto pilot or traffic aware cruise control. It didn't impact our infrequent use of the vehicle, but you definitely want to ensure it has the features you're looking for.

 

[E90alex]

2020 was rated at 322 EPA not 348. Early software versions actually still had it displaying 310 at 100% but was later updated to show 322. It still has the same battery as 2019 and older which is rated at 310.

Calculating the 100% range by just simple math isn’t usually accurate. First of all, rounding errors can make a huge difference. Depending if it’s truly estimating 74.5 mi or 75.4 mi or somewhere in between, and if it’s truly at 26.5% or 28.4% or somewhere in between, the calculated range number varies anywhere from about 262 mi to 285 mi which is between approximately 11-19% degradation. Simply taking the straight middle number would be 15% which I believe isn’t bad and about what is expected for that age.

But also keep in mind the BMS may be out of calibration and/or battery may be out of balance. Need to actually charge the car to 100% until it stops pulling power (can be minutes to over an hour after it displays 100%) to see what it estimates at true full capacity. If it is out of calibration it should show even more range once it’s recalibrated so it may in fact have less degradation in reality than what is calculated now.

Typical real world range is about 10-15% less than the displayed rated range.

 

[S Ramsay]

2020 was rated at 322 EPA not 348. Early software versions actually still had it displaying 310 at 100% but was later updated to show 322. It still has the same battery as 2019 and older which is rated at 310.

Calculating the 100% range by just simple math isn’t usually accurate. First of all, rounding errors can make a huge difference. Depending if it’s truly estimating 74.5 mi or 75.4 mi or somewhere in between, and if it’s truly at 26.5% or 28.4% or somewhere in between, the calculated range number varies anywhere from about 262 mi to 285 mi which is between approximately 11-19% degradation. Simply taking the straight middle number would be 15% which I believe isn’t bad and about what is expected for that age.

But also keep in mind the BMS may be out of calibration and/or battery may be out of balance. Need to actually charge the car to 100% until it stops pulling power (can be minutes to over an hour after it displays 100%) to see what it estimates at true full capacity. If it is out of calibration it should show even more range once it’s recalibrated so it may in fact have less degradation in reality than what is calculated now.

Typical real world range is about 10-15% less than the displayed rated range.

2020 was rated at 322 EPA not 348. Early software versions actually still had it displaying 310 at 100% but was later updated to show 322. It still has the same battery as 2019 and older which is rated at 310.

Calculating the 100% range by just simple math isn’t usually accurate. First of all, rounding errors can make a huge difference. Depending if it’s truly estimating 74.5 mi or 75.4 mi or somewhere in between, and if it’s truly at 26.5% or 28.4% or somewhere in between, the calculated range number varies anywhere from about 262 mi to 285 mi which is between approximately 11-19% degradation. Simply taking the straight middle number would be 15% which I believe isn’t bad and about what is expected for that age.

But also keep in mind the BMS may be out of calibration and/or battery may be out of balance. Need to actually charge the car to 100% until it stops pulling power (can be minutes to over an hour after it displays 100%) to see what it estimates at true full capacity. If it is out of calibration it should show even more range once it’s recalibrated so it may in fact have less degradation in reality than what is calculated now.

Typical real world range is about 10-15% less than the displayed rated range.

Thanks for that info, some websites said 322 miles and some said 348 for the 2020 version but I couldn't find a definitive source. Assuming that you're correct, I would feel much more relaxed going ahead with the purchase as 15% degradation is I understand fairly normal for that age and if it continued linearly then it would suffice for me for a long time. I will get the dealer to charge it to 80% before making a decision as that will reduce the rounding errors in the range estimate, and maybe recalibrate it myself at a later date if I buy it

 

[S Ramsay]

Bought the car, drove it a little over 106 miles home, mostly at 65-70 mph, and used 39% of the battery. That would translate into approx 275 mph on a single charge, pretty happy about that

 

[M3BlueGeorgia]

Bought the car, drove it a little over 106 miles home, mostly at 65-70 mph, and used 39% of the battery. That would translate into approx 275 mph on a single charge, pretty happy about that

Charge it to 90% and then (briefly) switch the battery display to EPA miles from percentage and divide by 0.9 to get the current range in EPA miles.

Because of the nature of Lithium batteries, the car estimating the remaining range is more art than science when in the 25% to 75% range, but 90% is more accurate.

BTW Always select the range in percentage as "EPA miles" can be seriously wrong in some road conditions.