He Called the Shelby GT350 the Best Mustang Ever in 2016 — Ten Years Later, He Bought One With a Seized Engine

Engineering Explained’s Jason Fenske spent a decade calling the Ford Shelby GT350 the greatest Mustang ever built before finally buying one. The 2018 model he found had a seized flat-plane-crank V8 and metal shavings throughout its oiling system. Here’s why he bought it anyway — and what the Voodoo engine’s quirks reveal about this car’s cult following.

In 2016, Jason Fenske ended his review of the Ford Mustang Shelby GT350 with a simple verdict: “in summary, buy one.” He didn’t — not for a decade, anyway. It wasn’t until this year that the Engineering Explained host finally tracked down a used GT350 he could call his own, a 2018 model he’d been thinking about since the day he first drove one. But the car that showed up at his door wasn’t the flawless machine he remembered testing years earlier. According to the dealership’s own service notes, its engine had already seized, the oil filter was packed with so much metal debris the technician called it “really bad,” and the car’s locked-out computer wouldn’t even communicate with a diagnostic tool. For most buyers, that would be a dealbreaker. For Fenske, it became the opening act of a video explaining exactly why he still thinks this is the greatest Mustang Ford has ever built — and why that engine is both the car’s glory and its Achilles’ heel.

A YouTuber Who Said “Buy One” Finally Took His Own Advice

Fenske’s channel has built its reputation on breaking down the engineering behind performance cars rather than just reviewing how they feel from the driver’s seat, and his history with the GT350 goes back to the car’s debut. He drove one shortly after its release and came away convinced it was something genuinely special — a factory Mustang with a heart borrowed from exotic sports cars. A decade of testing everything from hypercars to EVs later, he says the GT350 still holds its place in his personal list of all-time greats. So when a seized-engine 2018 model turned up needing a full replacement, he didn’t walk away. He bought it anyway, had the dealership install a new engine, oil cooler, and intake manifold, and turned the whole ordeal into a deep dive on what makes this car’s drivetrain so unusual in the first place.

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The dealership technician’s notes, which Fenske shared in the video, read like a small horror story for anyone shopping a used GT350: a seized engine, oil passages and the intake manifold fouled with metal shavings, and a tuned engine computer that blocked normal diagnostics. It’s the kind of used-car red flag that would scare off most buyers. But rather than treat it as a reason to avoid the car, Fenske used it as a reason to explain what’s actually happening inside the engine bay — and why the GT350’s reputation for being finicky is tied directly to the same engineering choices that make it so good to drive.

The Only American V8 With a Formula One Heartbeat

The centerpiece of the GT350 is its 5.2-liter “Voodoo” V8, and what makes it unusual isn’t its displacement or its horsepower figure — it’s the crankshaft. Nearly every American V8 ever built uses a cross-plane crankshaft, which staggers the firing order to produce that familiar deep, uneven burble. The Voodoo instead uses a flat-plane crank, a design far more common in Ferrari V8s and Formula One engines than anything wearing a Ford badge. A flat-plane crank allows the engine to rev dramatically higher because the reciprocating assembly is lighter and better balanced for high-RPM operation, which is exactly what the GT350 does: it revs all the way to the far end of the tachometer and makes the bulk of its power near redline, with an exhaust note that sounds nothing like a typical American V8 and everything like an angry European one.

That high-revving character connects directly back to the nameplate’s origins. The original Shelby GT350 was built in the 1960s as a homologation special — a street car built in just enough numbers to let Carroll Shelby’s race-prepped Mustangs compete, and it earned its reputation by being track-focused in a way ordinary Mustangs weren’t. Ford resurrected the GT350 name for the 2016 model year with that same mission in mind: build the most track-capable, engineering-forward Mustang the factory had ever offered, and give it a heart unlike anything else in the lineup. The flat-plane Voodoo V8 was the clearest expression of that goal, and it remains the only engine of its kind Ford has ever put into a mass-production car.

The Homologation Instinct Never Really Left

Ford didn’t stop at the standard GT350. A year into production, it introduced the GT350R, a track-only-minded version that stripped out the rear seat and swapped the standard wheels for the world’s first full production carbon-fiber wheels, built by Carbon Revolution in Australia. Between the carbon wheels, a carbon-fiber rear spoiler, and the rear seat delete, the R shed roughly 200 pounds compared to the regular GT350 — weight savings pulled almost entirely from rotating mass and the car’s extremities, exactly where a chassis engineer wants it gone. It’s a strategy that would have looked familiar to Carroll Shelby’s original team six decades earlier, who pulled the back seat out of the 1965 GT350 for the same reason: strip anything that doesn’t make the car faster around a track.

That parallel isn’t a coincidence. The modern GT350 program was built by engineers who understood exactly what made the original nameplate matter, and they leaned into it rather than softening it for a broader audience the way some other performance-Mustang programs have. Ford built the GT350 to be uncompromising — manual-only, naturally aspirated, tuned for lap times over drag-strip bragging rights — in an era when most performance-car makers were adding turbochargers and dual-clutch automatics to chase easier numbers. Reviewers at the time noted the car felt like Ford quietly building its answer to a Ferrari-style, high-revving driver’s car rather than just another muscle-car horsepower war entry, and that ambition is a big part of why a car this demanding still has owners defending it a decade later.

What a Seized Engine Reveals About the Voodoo’s Reputation

The Voodoo’s high-strung nature is also exactly why GT350 owners have spent years talking about oil consumption and engine health more than owners of almost any other modern Mustang. A flat-plane crank spinning to a sky-high redline puts more stress on bearings and oiling systems than a conventional cross-plane design, and the GT350 community has developed something of a maintenance culture around it — checking oil levels more frequently than the manual requires, installing aftermarket oil catch cans, and sending oil samples out for analysis after every change. Several owners who commented on Fenske’s video described exactly that routine: one reported pulling nearly 550 milliliters of collected “stuff” from a catch can over the life of his car, while another with over 45,000 miles said he still sends off an oil sample with every change just to keep tabs on wear.

None of that means every GT350 is a ticking time bomb — plenty of owners in the comments reported six-figure mileage with zero issues, including one who said a friend’s 2016 GT350 still “wings out to redline with no issues” at 160,000 miles. But it does mean the car Fenske bought wasn’t an isolated fluke; it’s a known enough pattern that an entire subculture of GT350 owners has organized their maintenance habits around protecting this specific engine. That’s the trade-off baked into building a race-bred, flat-plane V8 for road use: the same design that makes it sing at 8,000 RPM also makes it far less forgiving of neglect than a garden-variety pushrod V8.

Tremec Gears, a Torsen Diff, and Brembo Brakes: The Hardware Behind the Hype

The engine gets most of the attention, but the rest of the GT350’s hardware was chosen with the same singular focus. Power runs through a Tremec six-speed manual transmission — no automatic was ever offered on the GT350, a deliberate decision that kept the car firmly in enthusiast territory. A Torsen limited-slip differential manages power to the rear wheels for more consistent grip out of corners than a clutch-type diff typically provides, and the suspension uses Ford’s adjustable MagneRide magnetorheological dampers, which change stiffness in real time based on road conditions and driving mode. Brembo brakes handle stopping duty — six-piston calipers up front clamping 15.4-inch rotors, four-piston calipers in the rear — sized to match a car that Ford designed to spend real time on a road course rather than just posing in a dealership showroom. Ford quoted the standard GT350 at 0-60 mph in roughly 4.3 seconds, a number that undersells how the car actually behaves, since most owners and reviewers agree the real story is what happens after 60, when the Voodoo keeps pulling hard all the way to its 8,250-RPM redline instead of running out of breath the way a typical muscle-car V8 does.

It’s that complete package — not any single spec sheet number — that keeps owners defending the car so fiercely. In the comments under Fenske’s video, one owner described his modified 350R as “simply magical” at any RPM, another called the stock combination of a six-speed manual, 520-plus horsepower, and Brembo brakes enough to explain “your gigantic smile,” and a retired Ford dealership mechanic recalled the entire service staff being encouraged to spend a day driving one just so they’d understand what they were selling. Fenske’s own read on the car, even after inheriting someone else’s engine problem, hasn’t changed: he still calls it, without much hesitation, the best Mustang Ford has ever built.

Watch the full video above and let us know your thoughts in the comments.