NOCO GB40 vs GB50: Which Jump Starter Should You Buy?
The NOCO GB40 gives you 1,000 amps and handles gas engines up to 6.0L. The GB50 steps up to 1,500 amps and covers gas engines up to 7.0L and diesel up to 4.5L. If you drive a standard car or small SUV, the GB40 is enough. If you own a large truck, diesel vehicle, or want extra jump-start capacity, go with the GB50.
Your car won’t start. It’s dark. You’re alone. That moment is exactly why a portable jump starter matters. The NOCO GB40 and GB50 are two of the most popular options on the market — but they’re not the same device.
I’m Alex Rahman, and I’ve tested both units on everything from a compact sedan to a full-size pickup. The right choice depends on your vehicle and how you’ll use it. Let me break this down clearly so you can decide in the next five minutes.
- The GB40 delivers 1,000 amps and handles most passenger cars, SUVs, and motorcycles.
- The GB50 delivers 1,500 amps — 50% more power — and adds diesel engine support up to 4.5L.
- Both use NOCO’s UltraSafe spark-proof technology and work on any 12-volt vehicle.
- The GB50 weighs slightly more and costs about $50 more, but offers 30 jump-starts per charge vs. 20 for the GB40.
- For most everyday drivers, the GB40 is the smarter buy. Truck and diesel owners should get the GB50.
What Is the NOCO Boost Series?
NOCO is an American battery technology company known for its Genius charger line and portable jump starters. Their Boost series — which includes the GB40, GB50, and GB70 — launched its first generation around 2010 and has been one of the best-selling jump starter families on Amazon ever since.
The GB40 and GB50 both fall in the middle tier of the Boost lineup. They’re compact enough to fit in a glove box, powerful enough to start most real-world vehicles, and smart enough to protect against common user errors. That combination is why they’re consistently rated above 4.5 stars by tens of thousands of buyers.
NOCO GB40 vs GB50: Full Spec Comparison
| Feature | NOCO GB40 | NOCO GB50 |
|---|---|---|
| Peak Amps | 1,000A | 1,500A |
| Max Gas Engine | 6.0L | 7.0L |
| Max Diesel Engine | 3.0L | 4.5L |
| Battery Capacity | 24 Wh | 35 Wh |
| Jump Starts Per Charge | Up to 20 | Up to 30 |
| Flashlight | 100 lumens | 200 lumens |
| Weight | 2.4 lbs | 2.45 lbs |
| Dimensions | 6.6″ x 3.1″ x 1.7″ | 7.7″ x 3.4″ x 1.9″ |
| Hot/Cold Temp LEDs | No | Yes |
| IP Rating | IP65 | IP65 |
| Retail Price (approx.) | ~$99 | ~$149 |
How Much Power Do You Actually Need?
Here’s the thing — most drivers overestimate how much power they need. The GB40’s 1,000 amps is enough for the vast majority of passenger vehicles on the road today. A standard 4-cylinder sedan, a V6 SUV, even a smaller V8 truck — the GB40 handles them all without breaking a sweat.
The GB50 becomes the smarter buy when you’re dealing with larger engines. Think 6.2-liter V8 trucks, full-size diesel pickups, or diesel-powered work vans. At 1,500 amps, it gives you a reliable margin of extra power for cold-weather starts or deeply discharged batteries.
Cold weather reduces battery performance by up to 35%. If you live in a cold climate, bump up one power tier. A GB40 owner in Minnesota might want the GB50 just for winter confidence.
Both units use lithium-ion technology, which holds a charge for up to a year when stored correctly. That’s important — you don’t want to grab your jump starter in an emergency and find it dead.
What’s the Same on Both Models?
NOCO designed both the GB40 and GB50 around the same core platform. They share more features than they differ in. Here’s what you get on both:
- UltraSafe spark-proof technology — prevents sparks when connecting to the battery terminals
- Reverse polarity protection — alerts you if you connect the clamps backwards, preventing damage
- IP65 rating — sealed against dust and water splashes, but not full submersion
- USB output port — 5V/2.1A to charge phones, tablets, and other USB devices
- 7-mode LED flashlight — full, 50%, 10%, SOS, blink, strobe, and off
- 12V charging input — recharges via your car’s power port
- Manual override button — bypasses the automatic safety detection in extreme cases
- Rugged rubberized casing — scratch-resistant and impact-resistant outer shell
Both also ship with the same accessory package: precision battery clamps, a 12V car charger, a micro USB cable, and a microfiber storage bag. The GB40 does not come with a hard case, which is worth noting if storage protection is important to you.
Both models are spark-proof, reverse-polarity protected, IP65-rated, and include USB charging. The key differences are starting amps, battery capacity, diesel engine support, flashlight brightness, and temperature indicator LEDs.
Where the GB50 Wins: The 5 Real Advantages
The GB50 isn’t just marginally better — in specific situations, it’s significantly better. Here are the five real advantages it has over the GB40.
1. 50% More Starting Power
Five hundred extra amps isn’t a small thing. It’s the difference between a reliable start on a large V8 and a borderline attempt. If your truck has a 6.2-liter engine and a slightly weak battery, the GB40 might struggle. The GB50 won’t.
2. Diesel Engine Support Up to 4.5L
The GB40 maxes out at 3.0-liter diesel engines. The GB50 doubles that range to 4.5 liters. If you drive a diesel pickup, delivery vehicle, or boat with a diesel motor, the GB50 is the minimum you need. Don’t assume the GB40 will work — it might not.
3. 10 More Jump Starts Per Charge
The GB40 gives you up to 20 jumps per charge. The GB50 gives you up to 30. If you use your jump starter regularly — for multiple vehicles, a fleet, or a rental — that extra capacity matters. It also means you can share it with family members without constantly worrying about recharging.
4. Brighter Flashlight
The GB50 ships with a 200-lumen flashlight. The GB40 has 100 lumens. That’s twice the light output. In a dark parking garage or on the side of a highway at night, that difference is genuinely useful.
5. Temperature Warning LEDs
The GB50 adds hot and cold temperature indicator LEDs. The red LED warns you when the unit is getting too warm. The blue LED signals when it’s too cold to safely jump start. The GB40 doesn’t have these. In extreme weather, this safety information is valuable.
Never attempt to jump start a frozen battery. Both the GB40 and GB50 will alert you if conditions are unsafe — but only the GB50 has dedicated temperature LEDs. Always check the indicator lights before connecting the clamps.
Where the GB40 Wins: Why It’s Still the Better Buy for Most People
The GB40 isn’t a lesser product. For millions of everyday drivers, it’s the perfect product. Here’s where it earns its place.
Compact and Easy to Store
The GB40 is slightly smaller than the GB50 — about 1.1 inches shorter in length. That might not sound like much, but it’s the difference between fitting neatly in a glove box versus not. If space is tight, the GB40 wins.
$50 Cheaper
At roughly $99 versus $149, the GB40 saves you $50. For most drivers who’ll use this once or twice a year, that’s a real difference. You’re not leaving power on the table either — 1,000 amps is genuinely enough for most 4-cylinder and V6 vehicles.
Handles Everything Most Drivers Own
The vast majority of passenger cars on the road have engines under 4.0 liters. The GB40’s 6.0-liter gas engine limit covers almost every car, crossover, and mid-size SUV sold in the US. It’s the right tool for the right job.
The GB40 is Amazon’s #1 bestselling jump starter and has earned nearly 100,000 five-star reviews. That track record reflects millions of real-world success stories. Don’t feel like you’re buying the “lesser” model.
Who Should Buy the GB40?
The GB40 is the right choice if you drive:
- A compact car, sedan, or hatchback with a 4-cylinder engine
- A mid-size SUV or crossover with a V6
- A motorcycle, ATV, or small watercraft
- A lawn tractor or small utility vehicle
- Any gas-powered vehicle with an engine under 6.0 liters
It’s also the right choice if you want to save $50 and you’re confident your vehicle falls within its spec range. For most urban and suburban drivers, the GB40 is genuinely enough.
Who Should Buy the GB50?
The GB50 makes more sense if you drive or own:
- A full-size truck with a 6.2L or larger V8 engine
- A diesel-powered vehicle with an engine larger than 3.0 liters
- An RV, camper van, or large boat with a diesel motor
- Multiple vehicles and want one jump starter for all of them
- You work in a cold climate and want the extra safety margin
The GB50 is also the smarter buy if you use your jump starter frequently or want to lend it to others. More capacity means more uses before you need to recharge it.
Here’s a simple rule: if you’re not sure which engine size you have, check your vehicle’s manual or look at the engine displacement sticker under the hood. Then match it to the spec table above. That one number makes the decision easy.
How to Use a NOCO Jump Starter Safely
- Make sure the jump starter is charged — check the LED battery indicator first.
- Connect the red clamp to the positive (+) terminal of the dead battery.
- Connect the black clamp to the negative (–) terminal or a clean metal ground point.
- Power on the jump starter and wait 30 seconds before attempting to start.
- Start the vehicle — it should fire within 1 to 3 attempts.
- Disconnect the black clamp first, then the red clamp.
- Let the vehicle run for at least 15 minutes to recharge its battery.
Both the GB40 and GB50 will light up an error LED if you connect the clamps incorrectly. They won’t deliver power until the connection is safe. That’s the UltraSafe system doing its job.
GB40 vs GB50: Real-World Performance
On paper, specs tell one story. In the real world, user experience tells another. Here’s what actual owners report after extended use of both models.
GB40 owners consistently report success jump-starting everything from small sedans to full-size SUVs. One common theme is that the compact size makes it easy to keep in the car at all times — which is exactly what a jump starter should be.
GB50 owners report the same ease of use, with the added confidence of extra power. Several users note using the GB50 to jump-start diesel generators, excavators, and heavy equipment — well beyond its car-specific marketing.
Both models hold a charge for up to a year in storage. That’s critical for an emergency device. You don’t want to grab it after six months and find it dead.
For a deeper look at automotive battery technology, the MotorTrend automotive testing team and Consumer Reports both rank NOCO as a top-tier brand in the jump starter category.
The Best NOCO Jump Starter: Our Pick
For most drivers, the GB40 is the better value. It covers the vast majority of vehicles, costs $50 less, and has an unmatched real-world track record. If you drive a large truck or diesel vehicle, spend the extra $50 and get the GB50. You’ll use it with confidence every time.
NOCO Boost Plus GB40 1000 Amp 12-Volt UltraSafe Portable Lithium Car Battery Jump Starter Pack
The GB40 is the top-rated jump starter on Amazon — compact, safe, and powerful enough for most passenger vehicles. A must-have for any car owner.
Conclusion
The GB40 and GB50 are both excellent jump starters. Your vehicle’s engine size makes the decision for you. Most everyday drivers don’t need the extra power of the GB50 — but truck owners and diesel drivers do.
Pick the one that matches your engine. Don’t overthink it. Either way, you’ll have one of the best portable jump starters ever made sitting in your glovebox, ready when you need it.
I’m Alex Rahman, and both of these units have earned a permanent spot in my vehicle lineup — the GB40 in my daily driver and the GB50 in my truck.
Frequently Asked Questions
I’m Alex Rahman, a car enthusiast and automotive writer focused on practical solutions, car tools, and real-world driving advice. I share simple and honest content to help everyday drivers make better decisions.