Tesla announced improved battery ranges for some Model S and Model X vehicles ahead of first-quarter earnings

Bryan Logan/Business Insider

• Tesla announced a series of improvements to the Model S sedan and Model X SUV on Tuesday.
• Both vehicles received drivetrain upgrades that Tesla said would improve the battery performance on the long-range version of both cars to 370 miles for the Model S, and 325 miles for the Model X.
• The long-range Model S and Model X benefit from the extended range while using the same 100 kWh battery pack, according to Tesla.
• Additionally, the electric-car maker announced the lower-cost Standard Range Model S and Model X are once again available to purchase, a month after they were quietly removed from the Tesla website.
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Tesla is touting a handful of improvements to the Model S sedan and Model X SUV.

Both vehicles received drivetrain upgrades that Tesla said would improve the battery performance on the long-range version of both cars to 370 miles for the Model S, and 325 miles for the Model X.

The long-range Model S and Model X benefit from the extended ranges while using the same 100 kWh battery pack, according to a Tesla blog post published Tuesday.

The electric-car maker bundled a series of other announcements in its press release, including that it is bringing back the lower-cost Standard Range Model S and Model X, a month after they were quietly removed from the Tesla website.

Read more: Investors are looking for 3 things from Tesla's earnings

Additionally, the company introduced upgraded air suspension systems for both vehicles and said it is now offering a free Ludicrous Mode upgrade (normally a $20,000 option) for existing Model S and Model X owners who buy a brand-new Model S or Model X Performance vehicle, the priciest version of the cars in the lineup.

All of this news comes a day after CEO Elon Musk hosted an event - dubbed "Autonomy Day" - for investors on Monday. During the presentation, Musk touted Tesla's progress on its autonomous-driving technology.

The new-and-improved Model S and Model X also dropped just hours before Tesla is set to deliver its first-quarter earnings report. Wall Street analysts expect the automaker to swing to a loss after two straight profitable quarters, the Business Insider transportation correspondent Matt DeBord wrote earlier on Tuesday.

Musk said previously that Tesla would likely have a muted first quarter. The market has taken note of that projection, pricing in the expected loss accordingly.

Get the latest Tesla stock price here.