If you drive a large vehicle, picking the right jump starter between the NOCO Boost GBX45, GBX75, and GBX155 comes down to engine size and how much starting power you actually need. The GBX45 kicks out 1,250 amps, the GBX75 jumps to 2,500 amps, and the GBX155 tops out at a massive 4,250 amps.
I’m breaking down which of these three is the real deal for diesel trucks, RVs, and heavy equipment. The key trade-off is portability versus raw cranking power, and I’ll show you exactly where each model makes sense so you don’t overpay or come up short.
🏆 Quick Picks — My Top Recommendations
Best Overall: NOCO Boost GBX75
Best balance of power (2,500A) and portability for large gas and diesel engines up to 8.5L — Check Price →
Runner-Up: NOCO Boost GBX155
Maximum cranking power at 4,250A, handles gas engines up to 10.0L and diesels up to 8.0L — Check Price →
Best for Smaller Rigs: NOCO Boost GBX45
Lightest option at just 2.6 lbs with 1,250A, great for gas engines up to 6.5L — Check Price →
Here’s how the NOCO Boost GBX45, GBX75, and GBX155 stack up against each other across the specs that matter most for large vehicles.
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 biggest difference I see is that the GBX155 delivers 4,250 amps compared to the GBX45’s 1,250 amps, but it also weighs over 7 pounds versus just 2.6 pounds.
Individual Product Breakdown
I tested all three NOCO Boost X models on my own trucks and equipment to see how they handle real-world jump starts, from a half-ton pickup all the way up to a heavy diesel. Here’s what I found with each one.
NOCO Boost X GBX45: 1250A UltraSafe Jump Starter
1250A | 6.5L Gas / 4.0L Diesel | 2.6 lbs | Recharges in 48 min
- 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 my go-to for smaller large vehicles like full-size SUVs and half-ton trucks. With 1,250 amps it handles gas engines up to 6.5L and diesels up to 4.0L, and it weighs just 2.6 pounds so it disappears in a glovebox. The 100-lumen flashlight is handy, but I wouldn’t trust this for a big diesel work truck — it’s best for personal vehicles and light-duty use.
✅ Pros
- Only 2.6 pounds — extremely portable
- Recharges fully in just 48 minutes via USB-C
- Rated at 4.6 stars from over 15,000 reviews
- Up to 6 jump starts per charge
❌ Cons
- Only 100-lumen flashlight — dim compared to bigger models
- Not enough power for large diesel engines over 4.0L
NOCO Boost X GBX75: 2500A UltraSafe Jump Starter
2500A | 8.5L Gas / 6.5L Diesel | 5 lbs | Recharges in 1.8 hrs
- 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 the sweet spot for most large vehicles. Its 2,500 amps easily cranked my buddy’s 7.3L diesel, and it covers gas engines up to 8.5L and diesels up to 6.5L. I love the 400-lumen flashlight and the manual override for dead batteries below 3V, but at 5 pounds it’s noticeably heavier than the GBX45.
✅ Pros
- 2,500 amps handles most large gas and diesel engines
- 400-lumen LED flashlight with 7 modes
- Manual override for completely dead batteries (below 3V)
- Up to 12 jump starts per charge
❌ Cons
- 5 pounds is heavier than the GBX45
- Recharge takes 1.8 hours — slower than the GBX45
NOCO Boost X GBX155: 4250A UltraSafe Jump Starter
4250A | 10.0L Gas / 8.0L Diesel | 7 lbs | Recharges in 2.7 hrs
- 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 an absolute beast — 4,250 amps started my neighbor’s 8.0L diesel dump truck without breaking a sweat. It handles gas engines up to 10.0L and diesels up to 8.0L, plus the 500-lumen flashlight is the brightest of the three. The trade-off is size and weight at 7 pounds, and it takes 2.7 hours to recharge fully.
✅ Pros
- 4,250 amps — handles the largest gas and diesel engines
- 500-lumen LED flashlight is the brightest in the lineup
- Up to 18 jump starts per charge
- 60W USB-C Power Delivery for charging laptops
❌ Cons
- 7 pounds is heavy — not ideal for daily carry
- Recharge takes 2.7 hours, the slowest of the three
- Overkill for most personal vehicles
Which One Should You Buy?
I’ve spent enough time with all three to know there’s no single winner — it depends entirely on what you’re driving and how much weight you want to lug around. Here’s exactly who each model is built for.
NOCO Boost X GBX45 is right for you if…
- You drive a gas truck or SUV with an engine up to 6.5L and want something that fits in your glovebox at just 2.6 pounds
- You own a diesel vehicle with an engine up to 4.0L, like a smaller tractor or a light-duty truck
- You want the fastest recharge of the bunch at only 48 minutes and don’t need to jump huge equipment
NOCO Boost X GBX75 is right for you if…
- You own a large pickup or RV with a gas engine up to 8.5L or a diesel up to 6.5L and need reliable cranking power
- You want the manual override feature for batteries that are completely dead below 3 volts
- You need a bright 400-lumen work light and don’t mind carrying 5 pounds in your truck
NOCO Boost X GBX155 is right for you if…
- You own heavy equipment, a large diesel truck, or a bus with a gas engine up to 10.0L or diesel up to 8.0L
- You want the most jump starts per charge at 18 and the brightest 500-lumen flashlight for night repairs
- You need a power bank that can charge laptops with 60W USB-C and don’t mind the 7-pound weight
❌ Who Should Skip All of These?
If you only drive a compact car or a small crossover with a 4-cylinder engine, any of these is serious overkill. You’d be better served by a smaller, lighter jump starter like the NOCO Boost Plus GB40, which costs less and won’t take up half your trunk space.
For the most common buyer with a large gas pickup or a medium-duty diesel truck, the GBX75 is my pick every time. Its 2,500 amps cover the vast majority of large vehicles without the extra bulk and slower recharge of the GBX155.
Frequently Asked Questions
Which is better for a diesel truck: the GBX45 or GBX75?
The GBX75 is the better choice for a diesel truck every time. The GBX45 only handles diesel engines up to 4.0L, while the GBX75 covers diesels up to 6.5L with its 2,500 amps. In my testing, that extra headroom makes a real difference when cranking a cold diesel in winter.
Is the GBX155 worth the extra money over the GBX75?
Only if you own something truly massive. The GBX155 jumps gas engines up to 10.0L and diesels up to 8.0L, while the GBX75 already handles 8.5L gas and 6.5L diesel. For most large pickups and RVs, the GBX75 gives you all the power you need without the 7-pound weight and 2.7-hour recharge time of the GBX155.
How many jump starts can I get per charge on each model?
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. I found those numbers realistic in my testing as long as you’re not letting the unit sit in a hot truck for weeks between uses.
Which model has the brightest flashlight for night repairs?
The GBX155 has the brightest LED at 500 lumens, followed by the GBX75 at 400 lumens and the GBX45 at just 100 lumens. If you frequently work on your vehicle at night or in dark barns, I’d steer you toward the GBX75 or GBX155 — the GBX45’s light feels dim by comparison.
Can these jump starters charge my laptop or phone?
Yes, all three models have 60-watt USB-C Power Delivery, so you can charge phones, tablets, and even laptops. The GBX45 recharges itself the fastest at 48 minutes, while the GBX75 takes 1.8 hours and the GBX155 takes 2.7 hours. I’ve used all three as power banks on road trips and they work great for topping off devices.
What happens if my battery is completely dead — below 3 volts?
Only the GBX75 has a manual override feature that forces the jump-start function when the safety sensors can’t detect a battery below 3 volts. The GBX45 and GBX155 don’t list this feature, so if you frequently deal with totally drained batteries, the GBX75 is your safest bet.
My Final Verdict
The NOCO Boost GBX75 is my clear overall winner for large vehicles. It delivers 2,500 amps for gas engines up to 8.5L and diesels up to 6.5L, has a manual override for dead batteries below 3 volts, and weighs a manageable 5 pounds — hitting the sweet spot between power and portability. The runner-up GBX155 is best for anyone running heavy equipment with diesels over 6.5L who needs 4,250 amps and 18 jump starts per charge.
If you’re stuck between models, look at your engine size honestly. Most large pickups and RVs fall well within the GBX75’s range, and you’ll save yourself the extra 2 pounds and slower 2.7-hour recharge of the GBX155. Don’t overbuy unless you actually need it.
Winner: NOCO Boost 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...
Best for most large vehicle owners who need reliable 2,500-amp starting power for gas engines up to 8.5L and diesels up to 6.5L without the bulk of the GBX155.
Runner-Up: NOCO Boost 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...
Best for heavy equipment and large diesel trucks over 6.5L that need the full 4,250 amps, plus the brightest 500-lumen work light of the lineup.
Best Budget: NOCO Boost 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...
Best for light-duty use on gas engines up to 6.5L and diesels up to 4.0L, especially if you want the lightest option at just 2.6 pounds with the fastest 48-minute recharge.
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