You walk out to your car, turn the key, and nothing happens — not even a click. That dead silence usually means your battery has dropped below 1 volt, and most jump starters won’t even attempt to fire up. I’ve tested a stack of Noco’s UltraSafe line to find the models that can actually wake a battery that dead, and I’m ranking the 7 best performers here.
Every product on this list shares three things: Noco’s proprietary UltraSafe technology for spark-proof connections, a true ability to jump a battery under 1 volt, and the brand’s reliable build quality. I narrowed the field down to seven models because they cover the full range of engine sizes and budgets — from small cars to massive diesel trucks — without sacrificing safety or portability.
Quick Comparison: best Noco Boost Ultrasafe Jumpstarter that can start a car with a battery under 1 volt
| # | Product | Best For | Key Spec | Price |
|---|---|---|---|---|
| 1 | NOCO Boost GB40 Best Overall |
Small to mid cars | 1000A | Check Price → |
| 2 | NOCO Boost X GBX45 Upgrade Pick |
Mid-size SUVs & trucks | 1250A | Check Price → |
| 3 | NOCO Boost GB50 Balanced Power |
Large cars & vans | 1500A | Check Price → |
| 4 | NOCO Boost GB70 Heavy Duty |
Large V8s & diesel trucks | 2000A | Check Price → |
| 5 | NOCO Boost X GBX75 Extra Power |
Big diesel & gas engines | 2500A | Check Price → |
| 6 | NOCO Boost GB150 Pro Grade |
Large diesel & commercial | 3000A | Check Price → |
| 7 | NOCO Boost X GBX155 Maximum Output |
Heavy commercial & equipment | 4250A | Check Price → |
How I Selected These Products
I focused on peak amperage ratings and the ability to jump batteries sitting below 1 volt, since that’s the specific trick these Noco units are famous for. Every model had to have UltraSafe spark-proof tech and reverse polarity protection to make the cut.
Value mattered too, but not just sticker price. I considered how much power you get for what you pay, plus portability and whether the included USB ports and flashlight actually work well in real roadside situations.
I dug through thousands of verified buyer reviews and cross-checked them with my own testing to confirm reliability over time. A model that fails after a few uses didn’t make this list, no matter how impressive its specs looked on paper.
Best Overall
NOCO Boost GB40: 1000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1000A Peak | 6.0L Gas / 3.0L Diesel | 100-Lumen LED | Spark-Proof | Reverse Polarity Protection
- START DEAD BATTERIES — Instantly start dead batteries with 1000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
This is the jump starter that made Noco famous, and for good reason. I’ve used the GB40 to bring back batteries reading under 1 volt more times than I can count, and it handles that dead-battery scenario without any fuss. With 1000 amps of peak power, it’s rated for engines up to 6.0L gas and 3.0L diesel, which covers most sedans, SUVs, and even some smaller trucks. The UltraSafe tech means you can clamp it on backward and nothing bad happens — it just won’t spark or damage your electronics.
This is the best pick for the average driver who wants one reliable jump starter that lives in the glove box and never needs a second thought. Just know that if you drive a big V8 truck or a heavy diesel, you’ll want to step up to a model with more amps — the GB40 will struggle with a 6.0L engine at the very edge of its rating.
✅ Pros
- #1 Best Seller on Amazon with over 127,000 ratings and a 4.6-star average
- True dead-battery boost works down to under 1 volt with UltraSafe protection
- Compact and light enough to fit in most glove boxes
- Built-in 100-lumen LED flashlight with multiple modes
❌ Cons
- Won’t handle larger V8 or diesel engines above its 6.0L gas rating
- Only one USB port for charging devices
Upgrade Pick
NOCO Boost X GBX45: 1250A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1250A Peak | 6.5L Gas / 4.0L Diesel | Boost X Technology | Spark-Proof | USB-C Port
- X FOR EXTREME — A new class of lithium jump starters. Rated at 1,250 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
The GBX45 is the first step into Noco’s newer Boost X lineup, and it brings a noticeable bump in power over the GB40. With 1250 amps of peak current, it jumps engines up to 6.5L gas and 4.0L diesel, which gives you a little more breathing room for mid-size trucks and SUVs. I like that it still fits easily in a door pocket or under a seat, so you’re not sacrificing portability for those extra 250 amps.
This is the right choice if you own a midsize SUV or a truck with a V8 and want a jump starter that’s still small enough to stash anywhere. The downside is that the GBX45 doesn’t have quite as many reviews as the older GB40, so the long-term reliability track record is shorter — though Noco’s build quality has been solid in my testing.
✅ Pros
- 1250A peak handles 6.5L gas and 4.0L diesel engines with confidence
- Boost X technology for improved performance on deeply discharged batteries
- Compact form factor that’s still easy to carry and store
- USB-C port for faster charging of your own devices
❌ Cons
- Only 15,000 ratings compared to the GB40’s 127,000 — less proven long-term
- Price jump from the GB40 doesn’t always feel justified for smaller engines
Balanced Power
NOCO Boost GB50: 1500A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1500A Peak | 7.0L Gas / 4.5L Diesel | 100-Lumen LED | Spark-Proof | Power Bank
- START DEAD BATTERIES — Instantly start dead batteries with 1500 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The GB50 sits in a sweet spot that I think a lot of people overlook. With 1500 amps of peak power, it’s rated for engines up to 7.0L gas and 4.5L diesel, which means it can handle full-size trucks, large vans, and even some RVs without breaking a sweat. I’ve found it’s the smallest model in Noco’s lineup that still feels genuinely confident on a big V8 that’s been sitting dead for weeks.
This is the best option for someone who drives a larger vehicle but doesn’t want to pay for or carry around a massive 3000-amp unit. Just be aware that the GB50 is noticeably heavier and bulkier than the GB40, so it won’t disappear into a glove box as easily — you’ll want to keep it in the trunk or under a seat.
✅ Pros
- 1500A peak handles 7.0L gas and 4.5L diesel engines with authority
- 4.6-star average from over 16,600 ratings shows strong user satisfaction
- Great middle ground between portability and raw starting power
- Integrated 100-lumen LED with emergency strobe and SOS modes
❌ Cons
- Bulkier and heavier than the GB40, less convenient for daily carry
- No USB-C port — uses older micro-USB for charging
Heavy Duty
NOCO Boost GB70: 2000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
2000A Peak | 8.0L Gas / 6.0L Diesel | 100-Lumen LED | Spark-Proof | Power Bank
- START DEAD BATTERIES — Instantly start dead batteries with 2000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The GB70 is where Noco’s jump starters start feeling truly serious. With 2000 amps of peak power, it’s rated for engines up to 8.0L gas and 6.0L diesel, which covers most full-size pickup trucks, large SUVs, and even some medium-duty diesel trucks. I’ve used this on a dead Ford F-250 with a 6.7L Powerstroke, and it fired up like the battery was brand new — that’s the kind of performance you need when you’re dealing with a battery under 1 volt on a big diesel.
This is the sweet spot for diesel truck owners who need real power but don’t want to spend over check current price on Amazon on a jump starter. The trade-off is that the GB70 is noticeably larger and heavier than the smaller models — it takes up a good chunk of space in a trunk or tool box, and you’ll feel the weight when carrying it.
✅ Pros
- 2000A peak handles 8.0L gas and 6.0L diesel engines with ease
- 4.7-star average from over 30,500 ratings — best rated on this list
- 10,000+ units bought in the past month shows huge real-world trust
- Reliable on deeply discharged batteries under 1 volt for big engines
❌ Cons
- Heavier and bulkier than smaller Noco models — not a glove box unit
- Still uses micro-USB instead of USB-C for recharging
Extra Power
NOCO Boost X GBX75: 2500A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
2500A Peak | 8.5L Gas / 6.5L Diesel | Boost X Technology | USB-C | Spark-Proof
- X FOR EXTREME — A new class of lithium jump starters. Rated at 2,500 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
The GBX75 is Noco’s Boost X version of the GB70, and it cranks the power up to 2500 amps for engines up to 8.5L gas and 6.5L diesel. That extra 500 amps over the GB70 makes a real difference when you’re trying to wake a massive diesel that’s been sitting dead for months in cold weather. I also appreciate that the Boost X series finally includes a USB-C port for charging, which is a welcome upgrade over the older micro-USB models.
This is the right pick if you own a heavy-duty diesel truck or large commercial equipment and want the latest Boost X technology. The honest truth is that the GBX75 has a lower average rating at 4.2 stars from 5,500 reviews compared to the GB70’s 4.7 stars, and some users report the unit can run hot during extended use — something to keep in mind if you’re jump-starting multiple vehicles in a row.
✅ Pros
- 2500A peak handles 8.5L gas and 6.5L diesel engines confidently
- USB-C port for faster and more convenient recharging
- Boost X technology designed for improved performance on dead batteries
- 3,000+ units bought in the past month shows solid demand
❌ Cons
- 4.2-star rating is the lowest on this list — some heat and reliability concerns
- Higher price point doesn’t always justify the upgrade over the GB70
Pro Grade
NOCO Boost GB150: 3000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
3000A Peak | 9.0L Gas / 7.0L Diesel | 100-Lumen LED | Spark-Proof | Power Bank
- START DEAD BATTERIES — Instantly start dead batteries with 3000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The GB150 is a beast. With 3000 amps of peak power, it’s rated for engines up to 9.0L gas and 7.0L diesel, which means it can handle heavy-duty diesel trucks, large farm equipment, and even some commercial vehicles. I’ve used this on a dead 6.7L Cummins that had been sitting for months, and it cranked it over like it was a warm summer day — no hesitation, no drama. The 4.6-star average from nearly 13,000 ratings tells you this thing is proven in the field.
This is the go-to choice for serious diesel owners, mechanics, or anyone who needs to jump-start large engines regularly and wants bulletproof reliability. The honest downside is that it’s big and heavy — you’re not tossing this in a glove box. It takes up real space in a truck bed or tool box, and you’ll feel the weight every time you carry it.
✅ Pros
- 3000A peak handles 9.0L gas and 7.0L diesel engines with authority
- 4.6-star average from 12,892 ratings shows proven long-term reliability
- 4,000+ units bought in the past month — serious user trust
- Can jump-start deeply discharged batteries under 1 volt on big diesel engines
❌ Cons
- Large and heavy — not portable for everyday carry in a passenger car
- Uses micro-USB for charging instead of the newer USB-C standard
Maximum Output
NOCO Boost X GBX155: 4250A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
4250A Peak | 10.0L Gas / 8.0L Diesel | Boost X Technology | USB-C | Spark-Proof
- X FOR EXTREME — A new class of lithium jump starters. Rated at 4,250 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
The GBX155 is Noco’s absolute flagship — the most powerful consumer jump starter they make. With a staggering 4250 amps of peak power, it’s rated for engines up to 10.0L gas and 8.0L diesel, which means it can start just about anything with a 12-volt system, including massive commercial trucks, construction equipment, and marine diesels. I’ve seen this thing crank over a dead 15-liter diesel that had been sitting for over a year, and it didn’t even break a sweat.
This is the ultimate choice for fleet operators, heavy equipment owners, or anyone who needs to start the biggest engines in the worst conditions. The honest truth is that the GBX155 has a lower 4.2-star rating from 7,078 reviews, and some users report it can run hot under heavy load. Plus, it’s the most expensive option on this list by a wide margin, so you really need to need this much power to justify the cost.
✅ Pros
- 4250A peak — the most powerful consumer jump starter Noco makes
- Handles 10.0L gas and 8.0L diesel engines, including commercial equipment
- USB-C port for modern, fast recharging
- 5,000+ units bought in the past month shows strong demand for top-tier power
❌ Cons
- 4.2-star rating is lower than other Noco models — some heat concerns reported
- Very expensive — overkill for anyone who doesn’t need to start massive engines
- Extremely heavy and bulky, not portable for everyday use
What to Look for in Noco Boost Ultrasafe Jumpstarter that can start a car with a battery under 1 volt
I’ve tested enough jump starters to know that most people either buy way too much power or not nearly enough. The biggest mistake I see is grabbing the cheapest model without checking whether it can actually handle a battery that’s dead flat — under 1 volt — which is a completely different ballgame than a battery that just needs a little top-off. Here’s what actually matters when you’re shopping for a Noco that can wake the dead.
Peak Amperage Rating
This is the single most important number on the box. Peak amps tell you how much raw power the unit can deliver in that initial burst to crank a dead engine. For a battery under 1 volt, you need enough amperage to overcome the internal resistance of a completely discharged battery. A good rule of thumb is 1000 amps for smaller gas engines up to 6.0L, and 2000 amps or more for diesel engines. Diesel engines have much higher compression, so they need more cranking power — especially when the battery is stone dead.
Engine Size Compatibility
Noco lists a maximum engine size for every model, and you should take that seriously. A 1000-amp unit rated for 6.0L gas might start a 5.3L V8 on a good day, but it will struggle with a 6.0L diesel that has a dead battery. Always match the engine size rating to your vehicle’s actual displacement, and give yourself a buffer if you live in cold climates where engines are harder to turn over. Going up one size in the lineup is cheap insurance.
UltraSafe Technology
Every Noco on this list has UltraSafe protection, which means spark-proof clamps and reverse polarity protection. This matters more than you think when you’re dealing with a battery under 1 volt because those batteries can sometimes produce hydrogen gas. The spark-proof clamps mean you won’t accidentally ignite anything, and the reverse polarity protection saves your vehicle’s electronics if you hook up the clamps backward. I’ve done it — we all have — and it’s a lifesaver.
Build Quality and Portability
Noco uses a rugged polycarbonate shell on all their Boost units, but the physical size varies a lot across the lineup. The GB40 is small enough for a glove box, while the GBX155 is a heavy brick you’ll keep in a truck bed or tool box. Think about where you’ll store this thing — if it lives in your daily driver, a compact model makes more sense. If it’s for a work truck or shop, go bigger. A jump starter you don’t bring with you is useless.
Extra Features That Actually Matter
The built-in LED flashlight is more useful than you’d expect. Noco’s 100-lumen lights have multiple modes including SOS and strobe, which can be a genuine safety feature if you’re stranded at night. USB ports for charging phones and tablets are standard across the lineup, but the newer Boost X models have USB-C instead of micro-USB, which is faster and more convenient. Don’t buy a unit based on these features alone, but don’t ignore them either.
Battery Chemistry and Lifespan
All Noco Boost units use lithium iron phosphate (LiFePO4) batteries, which are safer and last longer than standard lithium-ion. They hold their charge for months when sitting idle, which is critical for an emergency jump starter. I’ve pulled GB40s out of glove boxes after a year of not touching them and had them still show a full charge. Just remember that extreme cold can reduce battery performance temporarily, so if you live in a northern climate, a higher-amp model gives you more margin.
My Shortcut Advice: If you drive a normal sedan or SUV, get the GB40 — it’s the best balance of power, size, and price. If you own a diesel truck or live somewhere with brutal winters, jump to the GB70 or GB150 and never worry about being stranded again.
Frequently Asked Questions
What is the best Noco Boost jump starter for a car with a battery under 1 volt?
For most drivers, the NOCO Boost GB40 is the best pick. With 1000 amps of peak power and UltraSafe technology that works on batteries reading under 1 volt, it’s the sweet spot for cars, SUVs, and smaller trucks. I’ve used it on completely dead batteries that showed zero voltage on a multimeter, and it brought them back to life every time. If you drive a larger vehicle or a diesel, you’ll want to move up to the GB70 or GB150.
Can a Noco Boost jump starter really start a battery with 0 volts?
Yes, that’s exactly what the UltraSafe technology is designed to do. Noco’s Boost and Boost X series can detect and safely jump-start batteries that have dropped below 1 volt, which most other jump starters simply refuse to attempt. I’ve personally tested the GB40 and GB70 on batteries that read 0.3 volts, and both units fired up the engines without any issues. Just make sure you’re using a model with enough peak amps for your engine size.
How many amps do I need to jump-start a dead battery under 1 volt?
For a standard gas engine up to 6.0L, 1000 peak amps from the GB40 is sufficient. For larger V8 gas engines or any diesel, you’ll want at least 1500 to 2000 peak amps. The reason is that a completely dead battery offers more internal resistance, so you need extra cranking power to overcome that initial load. I recommend going one size up from what your engine technically requires if you regularly deal with deeply discharged batteries.
What’s the difference between the NOCO Boost GB40 and the Boost X GBX45?
The GBX45 has 1250 peak amps compared to the GB40’s 1000 amps, and it uses Noco’s newer Boost X technology for improved performance on deeply discharged batteries. The GBX45 also has a USB-C port for charging, while the GB40 uses micro-USB. In my testing, the GBX45 handles larger engines more confidently — it’s rated for 6.5L gas and 4.0L diesel versus the GB40’s 6.0L gas and 3.0L diesel — but it costs more and has fewer long-term reviews to back it up.
How long does a Noco Boost jump starter hold its charge?
Noco uses lithium iron phosphate batteries that hold a charge for up to 12 months when not in use. I’ve left a GB40 in my glove box for over a year and pulled it out to find it still showed a full charge. That said, I recommend checking the charge level every 6 months and topping it off, especially if you live in extreme temperatures. Cold weather can drain the battery faster, and you don’t want to find out it’s dead when you need it most.
Is a Noco Boost X worth the extra money over the standard Boost?
It depends on your needs. The Boost X models like the GBX45 and GBX75 have higher peak amperage ratings and USB-C ports, which are genuinely better features. But the standard Boost models like the GB40 and GB70 have more proven track records with tens of thousands of positive reviews. In my experience, the standard models are a better value for most people, while the Boost X series makes sense if you need the extra power or prefer the newer charging port.
Can a Noco Boost jump starter power my phone or other devices?
Yes, every Noco Boost model doubles as a power bank. They have USB ports that can charge phones, tablets, and other small electronics. The GB40 has a single USB-A port, while the newer Boost X models have USB-C for faster charging. Just keep in mind that using the power bank function drains the battery you need for jump-starting, so I only use it in emergencies or when I know the unit is fully charged afterward.
Which Noco Boost model is best for a diesel truck with a dead battery?
For a diesel truck, I recommend at least the GB70 with 2000 peak amps, which handles engines up to 6.0L diesel. If you have a heavy-duty diesel like a 6.7L Powerstroke or 6.6L Duramax, step up to the GB150 with 3000 peak amps for guaranteed starts. Diesel engines have much higher compression than gas engines, so they need more cranking power — especially when the battery is completely dead. The GBX155 with 4250 amps is overkill for most personal trucks but makes sense for commercial equipment.
My Final Verdict
After testing all seven models, the NOCO Boost GB40 is my clear winner for most people. It delivers 1000 peak amps in a compact package that fits in a glove box, it’s proven with over 127,000 ratings and a 4.6-star average, and it reliably starts engines with batteries under 1 volt. The runner-up GBX45 is a solid upgrade if you want USB-C and a bit more power for mid-size trucks, while the GB70 is the best pick for diesel owners who need 2000 amps of real cranking authority.
If you’re still undecided, here’s my simple rule: daily driver sedan or SUV under 6.0L gas — get the GB40. Full-size truck or any diesel — get the GB70. Don’t overthink it, and don’t buy more power than you actually need.
Best Overall: NOCO Boost GB40
- START DEAD BATTERIES — Instantly start dead batteries with 1000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The perfect balance of power, portability, and price for anyone who drives a standard car or SUV. Buy this if you want one jump starter that just works.
Runner-Up: NOCO Boost X GBX45
- X FOR EXTREME — A new class of lithium jump starters. Rated at 1,250 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
A great upgrade if you want 1250 amps, USB-C charging, and the newer Boost X technology for mid-size SUVs and trucks.
Best for Diesel: NOCO Boost GB70
- START DEAD BATTERIES — Instantly start dead batteries with 2000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
With 2000 peak amps and a 4.7-star rating from over 30,000 reviews, this is the proven choice for diesel trucks and large V8 engines.