Honda's V6 Has Been Federally Investigated Three Times for Destroying Itself. 1.4 Million Are Still Running.

In November 2023, Honda recalled 248,999 vehicles after discovering that improperly manufactured crankshafts in its 3.5-liter V6 could cause connecting rod bearings to seize and engines to self-destruct while driving.^[1] Root cause: equipment with incorrect settings had ground the crank pins into a convex shape, starving the bearings of oil. Honda had known since 2020. It took three years to issue the recall and another three months to notify owners.

A year later, NHTSA opened a full investigation into 1.4 million vehicles equipped with the same engine. Not because the recall failed, but because 173 complaints rolled in from owners whose vehicles were never included in it. Their crankshafts came from different production batches. Their bearings seized anyway. One owner crashed.^[2]

Now, in August 2026, NHTSA has opened a third investigation. Complaint count: 414. Nearly triple the 2024 figure. Same engine, same failure mode, same five models across Honda and Acura: the 2016 through 2020 Pilot and MDX, the 2018 through 2020 Odyssey and TLX, and the 2017 through 2019 Ridgeline.^[3] All family-hauling workhorses. All powered by Honda's J-series V6, one of the most widely deployed six-cylinder engines in North America.

Connecting rod bearing seizure is not a gentle failure. When a bearing locks, the crankshaft can snap the connecting rod. Metal fragments ricochet inside the block. Oil pressure drops to zero. In the best scenario, you lose all engine power on a highway and coast to a shoulder with no power steering and fading power brakes. In the worst, the rod punches through the block and spills oil onto the exhaust manifold. Honda's own 2023 recall filing acknowledged the risks: engine damage, stalling, loss of power, fire.^[1]

Honda's explanation for the 2023 recall was reassuringly specific. One piece of manufacturing equipment. Incorrect settings. A quantifiable batch of bad crankshafts. Dealers would inspect engines, grind crankshafts to spec or replace them entirely. Problem contained. Except the problem was not contained. Four hundred and fourteen complaints from vehicles outside that batch is not noise; it is a pattern that Honda's root cause analysis either missed or scoped too narrowly. NHTSA's decision to reopen the investigation after closing the 2024 probe signals that the agency believes the same thing.^[4]

In FARS data, the five affected models account for 1,658 combined fatalities over the 2014 through 2023 reporting period.^[5] FARS does not isolate engine seizure as a crash contributing factor, so none of those deaths can be directly attributed to connecting rod failure. But the Odyssey alone carries an 864-death total with one of the lowest impairment rates in the database at 15.4%. Sober families in minivans, relying on the mechanical integrity of an engine that Honda has now admitted can fail without warning.

If you own a 2016 through 2020 Pilot, MDX, Odyssey, TLX, or Ridgeline with the 3.5-liter V6: Check your VIN at nhtsa.gov/recalls immediately. If your vehicle was included in the 2023 recall (23V-838) and you never brought it in, do so now. If your vehicle was not included, watch for a knocking or rattling sound from the engine bay, sudden oil pressure warnings, or any loss of power. File a complaint at nhtsa.gov/report-a-problem. Every complaint strengthens the data NHTSA uses to decide whether 1.4 million more engines need to come out.