What appears to be a new EPA certification application (surfaced on Rivian Forums) reveals the possible performance and range results of Rivian’s new in-house-built dual-motor Enduro drive unit. So far, the company relied on external suppliers for its electric motors, but now with its own drivetrain, it is expected to exercise more control over costs and production.

The in-house powertrain entered production last month for the R1S electric SUV and R1T electric truck. The new findings from the application indicate a small bump in range and performance compared to Rivian’s previous estimates.

Rivian estimated the range for its R1S with the all-terrain upgrade and the Large, 135-kilowatt-hour battery pack, to be 300 miles. The EPA estimate is slightly more optimistic at 305.79 miles, or roughly 2 percent better.

The brand projected the 2023 R1S with the 22-inch wheels to have a range of 320 miles, while the EPA figure is about 6 percent more at 340 miles. The same can be said about the longest-range R1S, which gets 21-inch wheels. Its initial range estimate was 340 miles, while the EPA figure is about 3.5 percent more at 352.06 miles.

Compared to the quad-motor version, the new dual-motor R1S with 22-inch wheels has about 11 percent more range, while the one with 21-inch wheels has roughly 9 percent more range.

How does EPA calculate these figures? According to one report, EPA multiplies its preliminary highway and city range results by 0.7 to account for different driving styles and conditions. Hence, the combined range figures you see in the images attached to this piece are adjusted using the aforementioned calculation.

The rated horsepower for the performance dual-motor all-wheel-drive variant has also marginally improved, from 700 to 708 horsepower, as per the document. The quad-motor version remains the quickest of all variants with 835 hp and a 0-60 miles per hour acceleration time of 3.5 seconds.

How do these figures compare to other electric trucks on the market? Check out our comprehensive all-electric car price and range comparison for insights. Also, leave your thoughts about the new EPA range estimates for the 2023 Rivian R1S in the comments.

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