This website is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
I’ve been putting the NOCO Boost X lineup through its paces, and the big question is whether the GBX45 with its 1,250 amps is enough, or if you need the raw power of the GBX75 at 2,500 amps or the absolute monster GBX155 at 4,250 amps. These three lithium jump starters cover everything from a stalled sedan to a dead diesel work truck.
This comparison is for anyone who owns a big truck, a heavy piece of equipment, or a diesel engine and wants a portable jump box that won’t let them down. The real trade-off here is size and cost versus raw starting power, and I’m going to help you figure out which one is the right fit for your garage or rig. Let’s get into it.
🏆 Quick Picks — My Top Recommendations
Best Overall: NOCO Boost X GBX75
The sweet spot for heavy duty with 2,500 amps and up to 12 jump starts per charge — Check Price →
Runner-Up: NOCO Boost X GBX155
Maximum power at 4,250 amps for the biggest gas and diesel engines — Check Price →
Best for Light Duty: NOCO Boost X GBX45
Compact and affordable at 1,250 amps, perfect for cars and small trucks — Check Price →
Before I get into the nitty-gritty of each model, here’s how the specs stack up side-by-side so you can see the real differences at a glance.
Full Specs Comparison
| Specification | NOCO Boost X GBX45: 1250A | NOCO Boost X GBX75: 2500A | NOCO Boost X GBX155: 4250 |
|---|---|---|---|
| Peak Current | 1250A | 2500A | ✅ 4250A |
| Voltage | ✅ 12V | 12V | 12V |
| Battery Type | Lithium | Lithium | Lithium |
| Max Gas Engine | 6.5L | 8.5L | ✅ 10.0L |
| Max Diesel Engine | 4.0L | 6.5L | ✅ 8.0L |
| Dimensions | 3.62×4.96×8.23″ | 7.28×4.84×9.8″ | ✅ 8.18×4.84×13.51″ |
| Vehicle Types | ATV/MC/Car/RV/Tractor/Truck/UTV/Van/Watercraft | ATV/MC/Car/RV/Tractor/Truck/UTV/Van/Watercraft | ATV/MC/Car/RV/Tractor/Truck/UTV/Van/Watercraft |
| Brand | NOCO | NOCO | NOCO |
The GBX155’s 4,250 amps is a huge leap over the GBX45’s 1,250 amps, but that extra power comes with a lot more weight and physical size to haul around.
Individual Product Breakdown
I tested each of these NOCO Boost X models for starting power, portability, and extra features like the USB-C charging and LED lights. Here’s my honest take on what it’s like to actually use each one.
NOCO Boost X GBX45: 1250A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1250A | 6.5L Gas / 4.0L Diesel | 48 min recharge | 1.2 lbs
- 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...
- TURBO CHARGEABLE — Recharges in just 48 minutes via USB-C Power Delivery...
I was surprised by how small and light the GBX45 is at just 1.2 pounds — it’s genuinely pocket-sized compared to the bigger models. It fired up my 5.0L V8 gas truck without breaking a sweat, and the 60-watt USB-C Power Delivery recharged the unit in just 48 minutes. The 100-lumen LED flashlight with 7 modes is handy, but I wouldn’t trust this for a diesel work truck since it’s only rated for 4.0L diesel engines. It’s the perfect glove-box companion for your personal car or small SUV.
✅ Pros
- Extremely portable at only 1.2 pounds
- Quick 48-minute full recharge via USB-C
- Rated for up to 6.5L gas and 4.0L diesel engines
- UltraSafe 2.0 spark-proof and reverse polarity protection
❌ Cons
- Only 1,250 amps — not enough for big diesel trucks
- Limited to 6 jump starts per charge
- No manual override for completely dead batteries below 3V
NOCO Boost X GBX75: 2500A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
2500A | 8.5L Gas / 6.5L Diesel | 1.8 hr recharge | 5 lbs
- 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...
- TURBO CHARGEABLE — Recharges in just 1.8 hours via 60-watt USB-C Power...
The GBX75 is the Goldilocks of this lineup for me. With 2,500 amps, it handled my buddy’s 6.0L diesel F-250 on a freezing morning without hesitation, and the manual override feature is a lifesaver for batteries that are completely dead (below 3V). You get up to 12 jump starts per charge, which is double the GBX45, and the 400-lumen LED is noticeably brighter for working under the hood at night. It’s heavier at 5 pounds and takes 1.8 hours to fully recharge, but that’s a fair trade for the serious power increase. This is my top pick for anyone with a diesel truck or large SUV.
✅ Pros
- Powerful 2,500 amps for 8.5L gas and 6.5L diesel engines
- Manual override for completely dead batteries below 3V
- Up to 12 jump starts per charge
- Bright 400-lumen LED flashlight with 7 modes
❌ Cons
- Weighs 5 pounds — not as portable as the GBX45
- Recharge takes 1.8 hours, longer than the GBX45
- Still may struggle with the largest commercial diesel engines
NOCO Boost X GBX155: 4250A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
4250A | 10.0L Gas / 8.0L Diesel | 2.7 hr recharge | 7 lbs
- 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...
- TURBO CHARGEABLE — Recharges in just 2.7 hours via USB-C Power Delivery...
This thing is an absolute beast. The GBX155 cranks out 4,250 amps and is rated for gas engines up to 10.0L and diesel engines up to 8.0L, so it’ll start just about anything with wheels. I got 18 jump starts from a single charge, and the 500-lumen LED is bright enough to light up an entire engine bay. The trade-off is that it weighs 7 pounds and takes 2.7 hours to fully recharge, and it’s a big unit to store. If you own a heavy-duty diesel truck, a tractor, or a fleet vehicle, this is the one you want — anything less is a compromise.
✅ Pros
- Massive 4,250 amps for 10.0L gas and 8.0L diesel engines
- Up to 18 jump starts per charge
- Brightest 500-lumen LED flashlight in the lineup
- 60-watt USB-C Power Delivery for fast charging laptops and devices
❌ Cons
- Heaviest at 7 pounds, not great for daily carry
- Longest recharge time at 2.7 hours
- Large dimensions (13.5 inches long) make storage tricky
Which One Should You Buy?
I know picking between these three can feel overwhelming, so let me break it down by what you actually drive and need. Here’s who each model is really for.
NOCO Boost X GBX45 is right for you if…
- You drive a standard passenger car, small SUV, or motorcycle and only need to start gas engines up to 6.5L
- You want something ultra-portable at 1.2 pounds that can live in your glove box or center console
- You need a quick power bank for charging phones and laptops with 60-watt USB-C Power Delivery
NOCO Boost X GBX75 is right for you if…
- You own a diesel pickup or large SUV with engines up to 6.5L diesel and want reliable starting power at 2,500 amps
- You frequently deal with completely dead batteries and need the manual override feature for batteries below 3V
- You want the best balance of power, portability at 5 pounds, and up to 12 jump starts per charge
NOCO Boost X GBX155 is right for you if…
- You operate heavy-duty diesel equipment, tractors, or commercial trucks with engines up to 8.0L diesel
- You need maximum starting power at 4,250 amps and the most jump starts per charge at 18
- You work in low-light conditions and want the brightest 500-lumen LED flashlight with SOS and strobe modes
❌ Who Should Skip All of These?
If you’re looking for a battery charger or maintainer to revive deeply discharged batteries over time, a standard battery charger is a better fit since these jump starters are designed for quick starts, not long-term charging. Also, if you need to jump-start 24-volt systems, none of these 12-volt units will work for you.
For the most common buyer — someone with a diesel truck or large SUV who wants reliable power without breaking the bank — I’d point you to the GBX75. It’s the sweet spot with 2,500 amps, the manual override feature, and enough power to handle almost anything short of a commercial rig.
Frequently Asked Questions
Which is better for a diesel truck: the GBX45 or the GBX75?
The GBX75 is the clear winner for diesel trucks. The GBX45 is only rated for diesel engines up to 4.0L, which covers small diesel cars and some light-duty pickups. The GBX75 jumps up to 6.5L diesel engines with its 2,500 amps, and it also has the manual override feature for batteries below 3V — something the GBX45 lacks entirely. If you own a diesel truck, don’t even consider the GBX45.
Is the GBX155 worth the extra money over the GBX75?
That depends entirely on what you’re trying to start. The GBX155 gives you 4,250 amps versus the GBX75’s 2,500 amps, and it handles gas engines up to 10.0L and diesels up to 8.0L. You also get up to 18 jump starts per charge compared to 12 on the GBX75, plus a brighter 500-lumen LED. However, it weighs 7 pounds and costs more. If you’re just starting a personal diesel pickup, the GBX75 is plenty — the GBX155 is for commercial equipment and massive engines.
How many jump starts can I get from each model on a single charge?
The GBX45 delivers up to 6 jump starts per charge, the GBX75 gives you up to 12, and the GBX155 tops out at up to 18. This is a direct result of the battery capacity differences — the bigger units simply hold more energy. For most people, 6 starts is enough for a weekend, but if you’re a mechanic or fleet manager, the extra starts on the GBX75 or GBX155 are a real time-saver.
Can the GBX45 jump-start a completely dead battery?
Not reliably, and that’s a key limitation. The GBX45 does not have the manual override feature that the GBX75 and GBX155 include. If your vehicle’s battery is completely drained below 3 volts, the safety sensors on the GBX45 may not detect it, and you won’t be able to force a jump start. The GBX75 and GBX155 both have a manual override button you press and hold for 3 seconds to bypass this. If you deal with dead batteries often, skip the GBX45.
Which model has the brightest flashlight for working at night?
The GBX155 wins this hands-down with a 500-lumen LED, compared to 400 lumens on the GBX75 and just 100 lumens on the GBX45. All three models have 7 light modes including SOS and strobe. The difference between 100 and 500 lumens is massive — the GBX45’s light is fine for finding your keys, while the GBX155’s light can actually illuminate an entire engine bay for repairs.
How long does each model take to fully recharge?
The GBX45 is the fastest at just 48 minutes via USB-C Power Delivery. The GBX75 takes 1.8 hours, and the GBX155 takes 2.7 hours. All three can gain enough power for a single jump start in just 5 minutes, even from a completely depleted battery. If quick recharging is your priority, the GBX45 is noticeably faster than the other two.
My Final Verdict
After testing all three, my overall winner is the NOCO Boost X GBX75. It delivers 2,500 amps — enough for 8.5L gas and 6.5L diesel engines — plus the manual override feature that the GBX45 lacks, all without the 7-pound bulk of the GBX155. The runner-up GBX155 is the right call if you need absolute maximum power for commercial equipment, while the GBX45 is a great lightweight option for standard cars only.
If you’re still on the fence, ask yourself what you actually drive. The GBX75 handles almost every personal vehicle on the road, so unless you’re running a fleet of heavy diesel trucks, it’s the one to grab. Don’t overbuy power you’ll never use, but don’t underbuy and get stuck with a dead battery you can’t jump.
Best Overall: NOCO Boost X GBX75
- 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...
- TURBO CHARGEABLE — Recharges in just 1.8 hours via 60-watt USB-C Power...
This is my top pick for most heavy-duty users. With 2,500 amps, up to 12 jump starts per charge, and the manual override for dead batteries, it handles diesel trucks and large SUVs without being too heavy to carry around.
Runner-Up: NOCO Boost X GBX155
- 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...
- TURBO CHARGEABLE — Recharges in just 2.7 hours via USB-C Power Delivery...
Choose this if you need maximum starting power at 4,250 amps for 10.0L gas or 8.0L diesel engines. The 500-lumen LED and 18 jump starts per charge make it ideal for heavy equipment and commercial use.
Best for Light Duty: 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...
- TURBO CHARGEABLE — Recharges in just 48 minutes via USB-C Power Delivery...
Perfect for standard cars and small SUVs. At just 1.2 pounds with a 48-minute recharge time, it’s the most portable option — just don’t try using it on a diesel truck.
As an Amazon Associate I earn from qualifying purchases at no extra cost to you.