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NOCO Boost GB40 Jump Starter

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NOCO Boost GB40 Jump Starter

The keep-one-in-every-car jump starter: 1,000 amps in a glovebox-sized box with clamps designed so you can't hook it up wrong.

  • Rated for gasoline engines up to 6.0L and diesels up to 3.0L.
  • Spark-proof, reverse-polarity-protected UltraSafe clamps.
  • Holds charge for months; doubles as flashlight and USB power bank.

$84.85

On Amazon when we checked (June 16, 2026) — live price may differ.

See price on Amazon

By Patrick Smith · Updated July 10, 2026 · How we review · We may earn a commission from Amazon links.

Price when checked
$84.85
on Amazon, June 16, 2026
Best for
Drivers of 4- and 6-cylinder cars, crossovers and smaller trucks — plus motorcycle, boat…
Biggest complaint
Deeply discharged batteries trigger an error light until you find the manual override; clamp cables run…

Reasons to buy

  • The punch-to-size ratio — starting 5.7L V8s from a glovebox-sized unit — plus the idiot-proof spark-proof clamps, months of charge retention, and the flashlight/power-bank extras.
  • Widely treated as the default 'one in every car' pick.

Reasons to skip

  • Deeply discharged batteries trigger an error light until you find the manual override; clamp cables run short; recharging takes 3-4 hours over micro-USB with no wall adapter included; and real-world jump counts (10-15) run below the advertised 20.

The GB40 is the jump starter that made cables-and-a-second-car feel obsolete: a 1,000-amp lithium unit the size of a paperback, with spark-proof, reverse-polarity-protected clamps that make it nearly impossible to hurt yourself or the car. Reviewers have started 5.7L V8s with it, it holds charge for months between top-ups, and the flashlight and USB power-bank output earn their space. Its limits are specific and worth memorizing: it's rated for gas engines up to 6.0L and diesels up to 3.0L, and when a battery is deeply discharged the safety circuit refuses to boost until you engage the not-so-obvious manual override (press and hold the boost button). Owners also note short clamp cables and a slow 3-4 hour recharge over micro-USB with no wall adapter included.

What buyers say

Our summary of recurring themes in customer reviews on the NOCO Boost GB40 Jump Starter Amazon listing (read July 2026) — not quotes or endorsements.

Most praised

The punch-to-size ratio — starting 5.7L V8s from a glovebox-sized unit — plus the idiot-proof spark-proof clamps, months of charge retention, and the flashlight/power-bank extras. Widely treated as the default 'one in every car' pick.

Most common complaint

Deeply discharged batteries trigger an error light until you find the manual override; clamp cables run short; recharging takes 3-4 hours over micro-USB with no wall adapter included; and real-world jump counts (10-15) run below the advertised 20.

Worked best for

Drivers of 4- and 6-cylinder cars, crossovers and smaller trucks — plus motorcycle, boat and mower owners. Worked worst on big-block V8s and larger diesels, which need a GB50/GB70-class unit.

Frequently asked questions

Why won't my NOCO GB40 jump my car?

If the vehicle battery is deeply discharged, the GB40's detection circuit won't send power and shows an error light. Engage manual override (press and hold the boost button) to bypass detection, and check the unit is charged with clean, solid clamp contact.

How big an engine can the GB40 start?

NOCO rates the 1,000A GB40 for gas engines up to 6.0L and diesels up to 3.0L. Bigger V8s and diesel trucks need a higher-output model like the GB50 or GB70.

NOCO Boost GB40 Jump Starter

$84.85 on Amazon when we checked (June 16, 2026). Amazon handles checkout, shipping and returns.

See price on Amazon →

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