Earlier this year, Tesla introduced new performance enhancements to Model S and Model X vehicles. The automaker never explained the impressive upgrade, which resulted in about 1-second faster 0 to 60 mph acceleration in almost all vehicle versions, beyond saying that it’s the result of both “software and hardware improvements.”

Now we learn that the company leveraged those improvements and they can implement them through a software update on some older Model S and X 75D vehicles for free.

The dual motor Model S and Model X vehicles with a 75 kWh battery pack were the most positively affected by the performance enhancements.

The Model S 75D’s 0-60 mph acceleration went down to 4.2 seconds from 5.2 seconds, while Model X’s went from 6.0 seconds down to 4.9 seconds.

All Model S and X 75D vehicles undelivered since July 1st had the update, but Tesla “spent the last few months validating” to see if the same update is possible for a broader range of their 75D fleet, according to an email sent to Tesla’s service staff and some potentially eligible owners verified by Electrek.

Interestingly, the update is not over-the-air as Tesla says it is “best managed through a hardwired connection” from Tesla’s Service centers.

The range of eligible vehicles is not exactly clear and Tesla’s service team will have to validate every VIN to see if the vehicles are eligible, but it looks like several Model S and X 75D owners could end up with a significantly quicker car after their next visit to a Tesla service center.

Apparently, some vehicles could not be eligible because of hardware differences and therefore, owners better check their VIN with their local service center before getting their hopes up. The update can take up to two hours and it is not mandatory if owners don’t want that extra acceleration for some reason.

Electrek’s Take

It’s an interesting move from Tesla that sheds some light on those mysterious performance enhancements from July.

We found it weird that Tesla didn’t want to elaborate on the significant acceleration upgrade beyond saying that it is from “software and hardware improvements.”

Right after the upgrade, a new part number for Tesla’s rear-wheel-drive electric motor showed up – indicating that the performance enhancements might be attributed to a new and improved motor, but today’s news shows that it seems to have more to do with software.

It looks like Tesla’s silence might have to do with them validating the possibility to extend that power uncorking to more vehicles over the last few months before elaborating on the upgrade.

Either way, it’s likely going to be an appreciated initiative from Tesla. The 75D is one of the automaker’s most popular options and with the recent discontinuation of the single motor configuration, it is now standard for both Model S and Model X.

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