NOCO Boost Plus GB40 Review: Honest Pros & Cons (2026)

The NOCO Boost Plus GB40 is a compact 1,000-amp lithium jump starter that fits in your glovebox and starts gas engines up to 6 liters. It includes spark-proof technology, reverse polarity protection, a 100-lumen flashlight, and USB charging. It’s the best pick for most car owners who want a safe, reliable jump starter without the bulk.

Your car battery dies. It’s 7 AM. You’re already late. No one is around to help. Sound familiar? That’s the exact moment the NOCO Boost Plus GB40 was built for.

I’m Alex Rahman, and I’ve tested portable jump starters for years. The GB40 keeps coming up as the go-to pick — but is it actually worth the $100? Let me show you what I found, including the parts most reviews skip.

What Is the NOCO Boost Plus GB40?

The NOCO Boost Plus GB40 is a portable lithium-ion jump starter made by NOCO (a US-based automotive tool brand). It’s designed to start a dead 12-volt vehicle battery without needing another car nearby.

NOCO launched this model as their mid-range “Boost Plus” option, sitting between the smaller GB20 and the more powerful GB50. The GB40 hits the sweet spot for most everyday drivers. It handles sedans, SUVs, half-ton trucks, motorcycles, and even boats.

Here’s what the specs look like at a glance:

Spec	Detail
Peak Amps	1,000A
Battery Capacity	24 Wh lithium-ion
Gas Engine Support	Up to 6.0 liters
Diesel Engine Support	Up to 3.0 liters
Weight	2.4 lbs (with clamps)
IP Rating	IP65 (water & dust resistant)
Jump Starts Per Charge	Up to 20
Operating Temperature	-4°F to 122°F (-20°C to 50°C)
Charge Time	3 hours via USB-C (2A)
Price (Typical)	~$100

How Does the NOCO GB40 Actually Work?

The GB40 uses a lithium-ion battery cell to store charge. When you connect it to your dead car battery, it delivers a burst of current to crank the engine. It’s the same idea as jumper cables — except you don’t need a second vehicle.

NOCO’s UltraSafe technology is the standout feature here. It detects the battery’s polarity before allowing current to flow. So if you clip the red clamp to the wrong terminal, nothing bad happens. The LED will flash red to warn you instead of sparking or damaging anything.

NOCO Boost Plus GB40 Pros: What It Gets Right

Here’s where the GB40 genuinely stands out against the competition.

1. The Clamps Are Surprisingly Good

Most budget jump starters use cheap, flimsy clamps. The GB40 doesn’t. NOCO uses the same clamp design on the GB40 as it does on its more powerful and more expensive models.

The jaws open wide and grip hard. They’re also narrow enough to squeeze into tight battery compartments — a real issue in modern vehicles where the battery is tucked under panels or near other components. That’s a feature you’ll appreciate the first time you actually need it.

2. Tiny Size, Real Power

The GB40 is 8 inches long and weighs 2.4 pounds. It fits inside a glovebox, a backpack, or under a seat. Don’t let the size fool you — this thing starts V8 trucks.

Testing showed it fired up a midsize SUV engine with ease, even when the battery was nearly fully drained. For most drivers with cars under 6 liters, the 1,000-amp output is more than enough.

3. Idiot-Proof Safety

The reverse polarity protection and spark-proof connection make this safe for anyone. You don’t need to know anything about electricity to use it. Connect, wait for green, start. That’s the whole process.

The IP65 rating means it handles rain, dust, and workshop grime. You’re not babying this thing — it’s built for real use.

4. Holds Charge for Months

One of the biggest fears with a jump starter is pulling it out during an emergency and finding it dead. The GB40 holds its charge for an extended time between uses. Many users report still finding charge after several months in their trunk. NOCO recommends a top-up every 3 to 6 months, which is easy to remember.

5. Cold Weather Performance

The GB40 is rated to operate down to -4°F (-20°C). Real users have confirmed it works in extreme cold — one reviewer used it at -15°F wind chill with a fully dead battery and it fired right up. That kind of reliability matters in winter climates.

NOCO GB40 Cons: Where It Falls Short

No product is perfect. Here’s what you should know before buying.

1. No Wall Charger in the Box

This is the most common complaint. The GB40 comes with a USB-C cable but no power brick. You’ll need your own USB-C wall charger. If you already have a fast charger at home, this isn’t a problem. But for a $100 device, NOCO should include one.

For best results, use a charger rated at 45W or above. Slow chargers stretch the charge time to 6 to 12 hours instead of 3.

2. No LCD Display

The GB40 uses LED indicator lights instead of a full display. You get battery level in rough percentage bands, not exact numbers. Some competing models at a similar price point offer small LCD screens. The LEDs are functional, but less precise.

3. USB Ports Are Slow

The USB-A output port is rated at 2.1A, and the USB-C is input-only. That means you can charge your phone from it — slowly. Don’t plan on using this as your main power bank or for fast-charging your devices. It works in a pinch, but it’s not built for that.

4. Battery Capacity Efficiency

The internal battery is rated at 24 watt-hours, but real-world testing found usable capacity closer to 15 to 16 watt-hours. That’s about 65% efficiency. Other NOCO models perform better in this area. It doesn’t hurt jump starting performance, but it limits how many phone charges you’ll get.

5. Durability Concerns After 12–18 Months

Some long-term users have reported the internal battery degrading significantly after 12 to 18 months, especially with inconsistent storage habits. The warranty is 1 year, which is standard but on the shorter side. Storing it at room temperature and maintaining the charge extends its life.

How to Use the NOCO Boost Plus GB40: Step by Step

The whole process takes under two minutes. You don’t need to read the manual every time — it’s that simple.

NOCO GB40 vs. GB50 vs. GB20: Which One Should You Get?

NOCO makes several Boost models. Here’s how the GB40 compares to its siblings so you can choose the right fit.

Model	Peak Amps	Gas Engine	Best For	Price
GB20	500A	Up to 4.0L	Small cars, motorcycles	~$70
GB40	1,000A	Up to 6.0L	Most cars, trucks, SUVs	~$100
GB50	1,500A	Up to 7.0L	Heavy trucks, large diesel	~$130
GBX45	1,250A	Up to 6.5L	Off-road, rugged use	~$120

For most drivers — anyone with a standard car, crossover, or half-ton truck — the GB40 hits the right balance. Go with the GB50 only if you drive a heavy-duty diesel truck or a large V8 engine above 6 liters.

What Battery Types Does the NOCO GB40 Support?

The GB40 works with virtually every 12-volt lead-acid battery type on the market. That covers the vast majority of vehicles sold in the US, Canada, and Europe today.

Compatible battery types include:

• Wet Cell (Flooded) — the most common type in older vehicles
• Gel Cell — used in motorcycles, ATVs, and some European cars
• AGM (Absorbed Glass Mat) — common in modern cars and stop-start systems
• EFB (Enhanced Flooded Battery) — found in many newer economy cars
• Maintenance-Free — sealed units in many modern vehicles

The GB40 does not support 6-volt batteries, 24-volt systems, or lithium-ion vehicle batteries (like those in some newer EVs and hybrids). For those, you’d need a different tool entirely.

Is the NOCO GB40 Safe to Use on Modern Cars?

Yes — and this is where NOCO genuinely stands apart. Modern vehicles are packed with sensitive electronics. A wrong connection or a voltage spike from a cheap jump starter can fry an ECU. That’s a $500 to $2,000 repair.

The GB40’s UltraSafe technology prevents current flow until it confirms a correct, safe connection. No spark, no surge, no risk to your car’s computer. It’s approved for use on modern vehicles, including those with start-stop systems and AGM batteries.

According to NOCO’s official product page, the GB40 is engineered specifically for safe operation on 12-volt systems with sensitive electronics.

Who Should Buy the NOCO Boost Plus GB40?

The GB40 is the right choice for most drivers. Here’s who it specifically suits best:

• Daily commuters who want peace of mind in parking lots or remote areas
• New drivers who want a beginner-friendly, mistake-proof jump starter
• Truck and SUV owners with gas engines up to 6 liters
• Off-roaders and van lifers who venture out alone and need self-rescue ability
• Anyone with an older vehicle whose battery is aging and less reliable

It’s less ideal for:

• Owners of large diesel trucks (6L+ diesel) — go with the GB70 instead
• People who need a serious power bank for camping or outages — the capacity is limited
• Fleet operators who need to charge dozens of vehicles — a commercial-grade charger makes more sense

Does the NOCO GB40 Work in Cold Weather?

Yes — better than most competitors. The GB40 uses high-discharge lithium technology rated down to -4°F (-20°C). Standard lead-acid booster packs lose 30 to 40 percent of their power output in freezing temps.

Real-world testing has confirmed it works reliably in sub-zero wind chill. If you live somewhere with harsh winters — Minnesota, Canada, northern Europe — this cold-weather performance is one of the GB40’s strongest selling points.

One note: lithium batteries do charge more slowly in cold temperatures. If you need to recharge the GB40 after a cold-weather use, bring it inside first and let it warm up before plugging it in.

How Long Does a Full Charge Last in Storage?

The GB40 holds a charge for months when stored properly. Most users report finding usable charge after 3 to 6 months without a top-up. NOCO recommends charging it every 3 months to maintain peak performance.

Store it at room temperature — not in a hot car or a freezing garage. This protects the lithium cells from stress and extends overall battery life. Following this single habit will keep the GB40 working well for 2 to 3 years or longer.

For more detail on lithium battery storage best practices, Battery University’s storage guide is a reliable resource.

NOCO GB40 vs. Other Portable Jump Starters

How does the GB40 stack up against popular alternatives? Here’s the honest comparison.

Brand / Model	Peak Amps	Safety Features	Display	Price
NOCO GB40	1,000A	Excellent (UltraSafe)	LED only	~$100
NOCO GB50	1,500A	Excellent (UltraSafe)	LED only	~$130
Clore JUMP-N-CARRY JNC660	1,700A	Basic	Gauge	~$120
Tacklife T8	800A	Moderate	LCD	~$50
Schumacher DSR116	1,200A	Good	LED	~$90

The GB40’s edge is its safety system and clamp quality. Cheaper alternatives like the Tacklife T8 have LCD displays, but they can’t match NOCO’s build quality or spark-proof engineering. For most people, paying $100 for the GB40 is smarter than risking a fry on your car’s electronics with a $50 unit.

Final Verdict: Is the NOCO Boost Plus GB40 Worth It?

The short answer? Yes — for most drivers, it’s the best jump starter at this price point.

The GB40 does exactly what it promises. It starts dead batteries fast, it’s safe enough for beginners, and it’s compact enough to keep in your car full-time. The clamps are excellent. The cold-weather performance is real. The safety features protect both you and your vehicle’s electronics.

The downsides — no included charger, slow USB ports, LED-only display — are real but minor. None of them affect its primary job: getting your car started when you’re stranded.

If your budget allows $100, buy the GB40 now and keep it in your car. You’ll be glad you did the first time your battery dies on a cold morning. — Alex Rahman

Frequently Asked Questions