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NOCO GB40 Crash Course

Portable jump starters like the NOCO GB40 provide the convenience of on-demand power when your battery dies.

Jumps various lead-acid batteries, including wet cell, gel, maintenance-free, enhanced flooded, and absorbed glass mat (AGM) batteries. 

Includes a built-in flashlight for working at night and a “USB Out” port for charging a phone or tablet.

Automoblog Review & Evaluation Process

During the winter of 2023, we received the GB40 portable jump starter from NOCO. While using the unit and writing this review, we kept three things in mind, outlined below.

NOCO GB40 Review Summary

Officially called the NOCO Boost Plus GB40, the 1,000-amp unit accommodates nearly all lead-acid car batteries, most gasoline engines, and smaller diesel powertrains. It’s easy to store as the entire unit with clamps and accessories is under 2.5 lbs. An integrated 100-lumen flashlight, built-in charging bank, and helpful safety features make the GB40 a good value for the money.

The NOCO GB40 usually retails for about $130, not counting any deals or specials. Below, we will cover the main features of the GB40 if you are in the market for a portable jump starter.   

NOCO GB40 In-Depth: What It Offers

The GB40 comes with detachable heavy-use clamps, a 40-inch micro USB cable for charging, a 12V 2.1-amp USB car charger, an owner’s manual, and a microfiber storage bag. The GB40 is only partially charged out of the box, so NOCO recommends fully charging it before use.

Internal Battery & Charging

Using the included micro USB cable and a USB wall charger, our GB40 took about three hours to charge fully. According to NOCO, the GB40 can provide up to 20 jump starts on a full charge in ideal conditions.

We have the GB40 in our winter emergency kit and charge it periodically, but we have been pleasantly surprised by just how long the unit holds its internal charge. That said, we have still gotten in the habit of charging it every so often, especially before a longer road trip. We want to ensure it’s ready to go if and when needed.

The GB40 has a 24-watt-hour lithium-ion internal battery with natural convection cooling. Meanwhile, the rubber housing covers for the 12V and USB outlets have an IP65 rating to protect against dust and water. NOCO engineered the GB40 to withstand temps as low as -4°F (-20°C) and as high as 122°F (50°C).

Battery & Vehicle Compatibility

The NOCO GB40 will jump various lead-acid batteries, including wet cell, gel, maintenance-free, enhanced flooded, and absorbed glass mat (AGM) batteries. Given the wide range of lead-acid battery compatibility, the GB40 is suitable for a vast majority of vehicles on the road today, whether brand new or gently used.

The GB40 will handle gas engines up to six liters, which covers a wide swath of half-ton trucks and every small to midsize SUV. Likewise, the GB40 will bring a smaller diesel mill (up to three liters) to life on a cold day.

It’s also handy around the garage or shed to jump any dead lawn and garden batteries. If you go camping or hit the trails, the GB40 can be used for almost any RV, marine, four-wheeler, or snowmobile battery.

Precision Clamps & Jumper Cables

One of the GB40’s top features is the detachable heavy-duty clamps (listed as “precision clamps” on the spec sheet). The shark-style, spark-proof design allows the clamp to bite down on batteries and terminals of different shapes and sizes.

The only potential downside is the relatively short length of the cables, which might be inconvenient depending on where your battery is located under the hood (although the shorter cables make for easier storage).

Instead of waiting on a friend with jumper cables or for roadside assistance, you pop the hood, hook the unit to your battery, and fire up your vehicle. Portable jump starters, like the NOCO GB40, are also great for winter emergency kits and extended road trips.   

Integrated Flashlight

On the GB40’s right bank is a 100-lumen flashlight (the bulbs are nestled on each side of the 12V outlet for the jumper cables). Hit the lightbulb button on the unit to access seven different modes, including an SOS beacon and emergency strobe. The constant-on modes have three different brightness settings, from higher to lower.

While the convenience and safety aspects of the flashlight are probably apparent, we did have occasion here at the office to use it during an afternoon snowstorm. Right around the time we received our GB40, the Detroit metro was hit with a storm that produced ice and heavy winds, knocking down trees and powerlines. We used the flashlight to walk down the stairs before heading out.

Charging Bank

That night, after we got home, the GB40’s USB charging port came in handy. On the unit’s left side are two 5V, 2.1A ports: USB In for charging the GB40 and USB Out for charging devices like tablets and phones. The built-in charging bank makes the NOCO GB40 more versatile and opens up other potential uses for the unit beyond jumping batteries.

The bright green light at the top indicates the NOCO GB40 is fully charged. When a proper battery connection is detected, the white 12V light will illuminate. Only at that time will the GB40 be able to deliver power. Photo: Alex Hartman.

Battery Management System

The GB40 is built on a proprietary software platform known internally at NOCO as the Battery Management System, or BMS. As described by NOCO, the BMS is responsible for key safety features and creating a “mistake-proof” product for customers.

With the BMS, the GB40 only outputs when it recognizes its cables are correctly attached to a battery. For example, if you accidentally connect to the wrong terminal (reverse polarity), the GB40 will not activate. Similarly, if the polarity is correct, but one of the clamps is loose, the BMS prevents the GB40 from delivering power.

With a proper connection, the white 12V LED light will illuminate on top of the unit. The GB40 will make an audible click, indicating that jumping the battery is safe (you can hear how that audible click sounds in our YouTube video of the GB40).

Rather than hitting everything it connects to at full blast, the NOCO GB40 only delivers the juice required by the battery needing a jump. Essentially, it can tell the difference between a lawnmower battery and a truck battery and adjust its power delivery accordingly.

Is The NOCO GB40 Worth The Money?

The compact, safety-focused design combined with the flashlight and charging bank make the NOCO GB40 a winner. While a dead car battery may happen only occasionally, the GB40 is something you would rather have and not need than need and not have.

If you want a portable jump starter for your emergency kit, the GB40 is a good pick. NOCO has more powerful units available, but the GB40 will suffice for most vehicle owners, and it’s priced reasonably for its performance.

We also own a 1200A Shell Portable Jump Starter, but the NOCO GB40 feels more durable with its hard protective casing, and the internal battery lasts longer. Our Shell is still a good unit, and we still plan to use it, but the NOCO GB40 is a welcome addition to our office garage.

Carl Anthony is the Managing Editor of Automoblog and the host of AutoVision News Radio and AutoSens Insights. As a respected automotive industry thought leader, Carl has appeared on numerous podcasts and radio shows, including Wrench Nation, Cars Yeah, The Car Doctor, and Brains Byte Back, in addition to appearing as a regular contributor on MotorMouth Radio on WHPC 90.3 FM. His work can also be seen and heard 24/7 on the Automoblog YouTube channel.

Photos: Alex Hartman.

Original article: NOCO GB40 Review: Small Portable Jump Starter With Big Value