Research from the database
Original analysis of NHTSA owner complaint and recall data, focused on the patterns that matter when you're buying, selling, or maintaining a used vehicle.
The GM 2.4L Ecotec: The Engine Behind the Equinox and Terrain's Oil Consumption Problem
GM built the same 2.4-liter Ecotec four into the Chevrolet Equinox and GMC Terrain for eight straight model years. The NHTSA record: 2,384 engine complaints, and owners in both nameplates describe the same pattern in the same order — a dipstick that reads low between changes, then a rattle at cold start as the timing chain wears. Median failure mileage lands between 80,000 and 100,000 miles.
The ZF 9-Speed: One Transmission, a Jeep, a Chrysler, and an Acura
Consumer Reports blamed Jeep for the notoriously balky 9-speed automatic in the 2014 Cherokee. But it was built by a German supplier, ZF Friedrichshafen, and the same transmission family also went into the Chrysler 200, the Jeep Renegade, and the Acura TLX — a Honda product with zero corporate tie to FCA. The NHTSA record: 6,137 powertrain complaints across all four, and the same hesitation-and-harsh-shift pattern in every one.
The VW/Audi 2.0T Timing Chain Tensioner
Volkswagen and Audi ran the same turbocharged 2.0-liter four across a decade of sedans, hatchbacks and crossovers. Its weak point was the timing chain tensioner — serious enough to draw a class-action settlement and an extended warranty. The NHTSA record: 1,679 engine complaints across the Jetta, Passat, Tiguan and Audi A4, most landing well inside 92,000 miles.
The Ford 5.4L Triton 3V: Spark Plugs and Cam Phasers, Right at 80,000 Miles
Ford's 5.4L 3-valve Triton V8 ran the F-150, Expedition, and Navigator for a decade. Ask any independent shop what it's known for and you'll get the same two answers: the spark plugs, and the cam phasers. The NHTSA record backs both up — 917 engine complaints, clustered in an unusually narrow mileage window.
The Car Brands Owners Complain About Most, Per Model
Raw complaint totals just name the best-seller. Divide each brand's NHTSA owner complaints by how many model-years it fields and a real order appears: Jeep tops the list at ~475 per model-year, the American brands cluster near the top, and Toyota and Honda land mid-pack. The full ranking — and the honest caveat about what 'per model' does and doesn't measure.
The Most-Complained-About New Car of Every Model Year
For every model year from 2005 to 2025, the single vehicle owners filed the most NHTSA complaints against. Ford dominates the annual title and the 2010 Fusion leads with more than 5,000 complaints. Why the count tracks sales and time on the road — and how to read the list honestly.
The Most-Complained-About Car Transmissions of the Last 20 Years
Ten transmission families, 171,000 NHTSA complaints. Raw volume just rewards a long production run; normalized per model-year, Ford's DPS6 PowerShift is the most-complained-about transmission per vehicle of the last twenty years. The full ranking — and where the crashes cluster.
One Transmission for the Whole Lineup: The Nissan Jatco CVT Failure
Nissan standardized on the Jatco CVT across the Altima, Sentra, Rogue, Versa and Pathfinder — so one weakness shipped in everything. Owners filed more than 4,400 powertrain complaints on the 2013–2019 cars. Most break at mid-life; the 2013 Pathfinder's failures cluster at a median of 10,000 miles.
Coolant in the Cylinders
No vehicle draws more engine complaints in the NHTSA record than the Ford Escape. Two small turbo EcoBoost engines, one root cause — coolant reaching the cylinders. The 1.6L overheated, caught fire, and got recalled; the 1.5L cracked its block, drew 3,110 complaints across three model years, and never got an engine recall. The data, and the ~80,000-mile failure window.
The GM 3.6 V6 Timing Chain
The Theta II got the headlines and the class action. GM's 3.6L LFX/LLT V6 — the only engine in the Lambda crossovers (Traverse, Acadia, Enclave, Outlook) — throws the same P0008/P0009 timing-chain-stretch code around 90,000 miles, and never got a recall for it. The engine-complaint record, isolated to the platforms where a complaint can only mean the V6.
A Honda Engine Problem That Depends on the Weather
In Texas nobody talks about the Honda 1.5T. In Minnesota the dealer cut your oil-change interval in half. The L15B7 turbo drops fuel in the oil pan on cold-start, short-trip driving — and on the 2017 CR-V the median complaint mileage was 14,000. Where it hits, and why the same engine looks different in different ZIP codes.
A Recall Covers One Defect. It Is Not a Clean Bill of Health.
A recall is one defect the manufacturer was forced to fix; it is not a verdict on the whole car. Here are widely-driven vehicle systems owners complain about by the hundreds with no recall for that system — each one cross-checked against the live NHTSA recall record.
The Theta II Decade
A decade of Hyundai and Kia Theta II rod-bearing failure plotted by model year against the recall timeline that chased it. 2013 was the worst year. 2019 brought a software band-aid. 2020 brought a settlement. The cars are still on the road.
Tires Before Engines
Owners report each vehicle system failing at very different odometer readings. We pulled 308,855 owner-reported mileages across 7,634 NHTSA problem clusters and aggregated by component category. Tires cluster near 30,000 miles. Engines and suspension at 70,000. The maintenance roadmap on a used car looks nothing like buyers assume.
Not All CVTs Are Equal
They're both called "CVT," but the NHTSA record splits them cleanly. Nissan's belt-and-pulley unit draws about 6.5 times the powertrain complaints per model-year of Toyota's planetary eCVT, with failures clustering around 82,000 miles. The belt is the difference.
When Things Break, in Actual Miles
For decades, "at what mileage will it fail?" was a guess. NHTSA's mileage field is now populated in our database, so we plotted ten famous engine and transmission failures by when owners actually filed. Some hit at 14,000 miles. Some hold until 90,000.
The Ford Transmission Nobody Recalled
Everyone knows the Ford PowerShift. Almost nobody talks about the 6F35, which quietly accumulated four times the NHTSA owner complaints at a comparable per-car failure rate. One got a $35M settlement. The other got a software flash.
7% of Vehicles, 39% of Complaints
When you actually count up the NHTSA owner complaints filed against the engines and transmissions everybody in the shop world already knows are problems, how big is that pile? We pulled the data and counted.