Dual-Motor Rivian R1T Is a More Efficient, Less Expensive Electric Pickup

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Electric truck manufacturer Rivian hit the ground running with the R1T pickup and, most recently, the R1S SUV with its powerful and capable Quad-Motor powertrains. However, as impressive as they are, four electric motors is probably overkill for most light duty drivers, which brings us to the Dual-Motor versions of the R1T and R1S, rolling off of the assembly line at Rivian’s Normal, Illinois headquarters and factory today.

With half the motors of its predecessor, the Dual-Motor powertrain promises improved range at a lower cost than Rivian’s current Quad-Motor offerings with surprisingly little trade-off to performance and power, thanks mostly to the automaker’s new generation Enduro electric drive units. I traveled to Rivian HQ to see the new Dual-Motor Enduro powertrain being built and compare it head-to-head on the automaker’s street and off-road test tracks with the familiar Quad-Motor version.

The Enduro drive unit

If you’re a delivery driver, you may have already experienced Rivian’s new electric motor without knowing. Manufactured for Amazon — and also used as Rivian’s own mobile service vehicle — the single-motor, front-drive Rivian Electric Delivery Van (EDV) was the first vehicle to feature the new Enduro drive unit, which now makes its way into the new R1T and R1S Dual-Motor AWD models.

Each Enduro drive unit integrates the motor, transmission, differentials and power electronics into a single compact housing

Antuan Goodwin/CNET

The Dual-Motor EVs make 533 horsepower and 610 pound-feet of torque, punching it to 60 mph from a stop in just 4.5 seconds. Stepping up to the Performance Dual-Motor configuration bumps output to 665 hp and 829 lb.-ft. and shaves the 0-to-60 mph sprint to 3.5 seconds, just 0.5 ticks short of the 835 hp, 908 lb.-ft. Quad-Motor’s time.

Enduro features a new stator and rotor — the stationary and rotating magnetic parts of an electric motor — that are assembled in-house at Rivian’s plant in Normal. (The R1 Quad-Motor’s Origin units source off-the-shelf rotors and stators.) The new stator uses 240 hairpin wires with a flat profile, squeezing more coils in closer for more efficient packaging and operation than round wires. Building in-house allows Rivian’s engineers to tightly integrate the entire drive unit, combining the electric motor, the inverter and three-phase power electronics, the two-stage reduction gear set, an open differential and, for the rear unit, an axle disconnect clutch into one housing that’s around 60 pounds lighter than a single Origin motor.

Rivian Enduro Power Control Unit

The new silicon-carbide MOSFET power module is 99% power efficient, versus the around 98% efficient silicon IGBT tech used prior. It’s a small difference that adds up to around a 3.5% range improvement for this generation.

Antuan Goodwin/CNET

Dual-Motor AWD

Of course, there are only two Enduro units per Dual-Motor chassis, as opposed to four Origins in the Quad, which saves even more weight. The rear-motor uses a higher final drive ratio (13.7:1) than the front (11:1), creating a rear-biased torque distribution that Rivian says improves driving feel and fun. The torque split can range from 50:50 to 30:70 during all-wheel operation depending on the drive mode. Enduro also introduces a dynamic rear-motor clutch that can automatically decouple the rear axle when cruising in the default All-Purpose drive mode to boost range, and then instantly re-engage the rear motor when passing or climbing power is needed or slip is detected. (The Quad-Motor EVs could only rear-disconnect by manually selecting the Conserve mode on the dashboard display.)

Rivian also employs brake-biasing to shuffle power laterally across the axle, which comes with its own advantages and disadvantages versus the one motor per wheel Quad setup. Driven back-to-back with the Quad-Motor R1T, the Performance Dual-Motor R1T feels nearly identical on the street. However, when tackling Rivian’s short off-road course, the Quad-Motor setup felt more sure-footed, particularly in situations where one or more wheels would lose contact with the ground, such as rock crawling or transitioning between severe opposite cambers. The Dual-Motor system was a touch slower to adjust — requiring patience and a steady pedal foot while the brakes built pressure on the lifted wheel to send torque back through the open diff — but it handled every obstacle that the Quad did safely and impressively.

For daily driving and weekend adventures, the R1 Dual-Motor powertrain should be capable enough for all but the most hardcore EV offroaders.

Rivian

Drive modes and towing

The R1 Dual-Motor’s simplified software reduces the EV’s drive mode programs to just All-Purpose, All-Terrain, Snow and Towing, skipping the specialized Rally, Drift, Rock Crawl and Soft Sand drive modes present on the Quad-Motor. And of course, there’s no longer need for a Conserve program, thanks to that dynamic rear axle. Performance Dual-Motor AWD models feature an additional Sport program that locks the powertrain into full-time all-wheel drive and adds a “Lowest” selectable ride height.

Finally, all R1 EVs feature a Towing mode that preps the vehicle to haul heavy loads and brings trailer braking systems online. The R1T pickup is capable of dragging up to 11,000 pounds, while the R1S SUV is rated for 7,700 pounds. I was able to experience the former during a ride-along in the passenger seat of an R1T Dual-Motor pulling Rivian’s EDV service van on a flatbed trailer. The van, trailer and the full complement of onboard tools was said to weigh around 9,800 pounds and the R1T still accelerated, braked and cruised acceptably.

The 9,800-pound EDV and trailer are well within the R1T Dual-Motor’s maximum towing capacity.

Antuan Goodwin/CNET

Battery packs and range

At launch, the Rivian R1T and R1S Dual-Motor will be offered with the automaker’s Large battery pack and up to 352 miles of estimated EPA range, an improvement over the 314 to 316 miles the Quad-Motor returns with the same battery. Post-launch, the automaker plans to roll out an even larger Max battery pack with up to 410 miles for R1T or 390 miles for R1S and, eventually, a smaller 260-270 mile Standard pack for the base non-Performance models.

Rivian Dual-Motor models

Model Range Horsepower Torque Price
R1T Dual-Motor Standard 270 miles 533 hp 610 lb.-ft. $73,000
R1T Dual-Motor Large 352 miles 533 hp 610 lb.-ft. $79,000
R1T Dual-Motor Max 410 miles 533 hp 610 lb.-ft. $89,000
R1T Dual-Motor Performance Large 352 miles 665 hp 829 lb.-ft. $84,000
R1T Dual-Motor Performance Max 410 miles 665 hp 829 lb.-ft. $94,000
R1S Dual-Motor Standard 260 miles 533 hp 610 lb.-ft. $78,000
R1S Dual-Motor Large 352 miles 533 hp 610 lb.-ft. $84,000
R1S Dual-Motor Max 390 miles 533 hp 610 lb.-ft. TBD
R1S Dual-Motor Performance Large 352 miles 665 hp 829 lb.-ft. $89,000
R1S Dual-Motor Performance Max 390 miles 665 hp 829 lb.-ft. TBD

The extra range and lower price are well worth the slight tradeoff to extreme rock-crawling performance.

Antuan Goodwin/CNET

The Rivian R1T and R1S Dual-Motor will start at $73,000 and $78,000, respectively, when the Standard battery becomes available. Currently, with the Large battery, $79,000 and $84,000 gets you in the door, around $8,000 less than a comparably equipped Quad-Motor EV. The Large battery Performance models climb to $84,000 for the R1T and $89,000 for R1S — only around $3,000 saved versus the Quads, but still money in the pocket at the end of the day. 

Considering how closely the Enduro-powered R1T performed back to back with its more complex predecessor, both on and off of the road, the Dual-Motor configuration’s increased range and reduced price make it a much better value as a daily driver for most drivers most of the time. As the saying goes, sometimes less is more.


Editors’ note: Travel costs related to this story were covered by the manufacturer, which is common in the auto industry. The judgments and opinions of CNET’s staff are our own and we do not accept paid editorial content.



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