Out of Spec Reviews just got the Pebble Flow delivered to their facility in North Carolina and wasted no time hitching it to a Rivian R1T for a first tow test. The Pebble Flow is an electric travel trailer with a 45 kWh LFP battery and two 60 kW hub motors built into the rear axle. In its Easy Tow mode, those motors are designed to offset the trailer's drag as you drive, reducing the load on the tow vehicle. The hardware numbers sound imposing, but the out-of-the-box towing tune is deliberately conservative, producing roughly 14 to 15 kW of forward push at highway speeds. That is a fraction of what those motors are physically capable of, and it is noticeably lower than what the competing Lightship L1 delivered when Out of Spec tested that trailer previously. Pebble says a more aggressive tune is coming in a future software update.
The Pebble Flow is priced starting at $109,000 and sits in direct competition with the Lightship L1, which starts at $125,000. Both use hub motors and onboard batteries to offset tow drag, but they take different technical approaches. The Lightship used dual force sensors in the hitch pin to measure exactly how hard the trailer was pulling or braking at any moment, giving it precise, near-instantaneous feedback for its tow-assist logic. The Pebble appears to have no hitch force sensor, relying instead on accelerometers or software-inferred vehicle state. The crew spent considerable time on camera puzzling over how the assist logic is even triggered, describing the transition between push and regen modes as feeling almost instantaneous despite the absence of any obvious sensor. That is either very clever software or a sign that the tuning is conservative enough that it avoids edge cases entirely. Probably both.
The first-night impressions on the highway were genuinely positive. Cruising at 70 mph behind the Rivian with Easy Tow engaged, the trailer tracked dead straight over bumps, showed no sway tendency, and the driver noted he could barely tell something was behind him. The braking system is also notable: the Pebble has a built-in trailer brake controller that activates automatically when towing a vehicle without one, and it defers to the tow vehicle's integrated controller when one is present. At highway speed, even in regen mode draining back up to 30 kW, the sensation in the cab was described as imperceptible. The crew noted a few early gripes: exterior lighting is sparse, the interior lights pulsed at medium brightness, and the parking brake automatically locks five minutes after the trailer stops moving, requiring an app code each time you want to reposition it. Not dealbreakers, but noticeable on day one.
Bottom line: The Pebble Flow's highway stability is legitimately impressive for a first tow, and the ease-of-use promise, particularly the self-hitching and self-parking capabilities, addresses real pain points for trailer owners. But the tow-assist output in its current tune is underwhelming given the hardware on board. At $109,000, buyers deserve the option to run these motors at their full potential on shorter trips. The software update Pebble has promised should be the real test of whether this system competes seriously with the Lightship's hitch-force-sensor approach. Until then, it is a very nice trailer with half its powertrain sitting idle.