Last updated September 10, 2026
NOCO Boost X GBX45 Review
The GB40's newer-generation sibling — 1,250A, a 6.5L gas / 4.0L diesel rating, and 60W USB-C that recharges the pack in under an hour.
The verdict
The GBX45 is what the GB40 should have become: a little more cranking margin, a diesel rating that covers small turbodiesels, and — the real upgrade — a 60W USB-C port that refills the pack in about 48 minutes and doubles as a laptop-class power bank. It's the same glovebox size and the same -4°F operating floor, so it's still a four- and six-cylinder pack, not a V8 truck pack. For roughly $15 over the GB40, we'd take the GBX45 unless the GB40 is on a deep sale.
Typical price: ~$115 (typical street price — current price shown on Amazon)
Buy on AmazonWhat we like
- +1,250A rating covers gas engines up to 6.5L and diesels up to 4.0L — more headroom than the GB40 on a cold V6
- +60W USB-C Power Delivery in and out: full recharge in about 48 minutes, and it fast-charges a phone or laptop
- +'0% to boost in 5 minutes' — a few minutes on a charger is enough to attempt a jump if you've let it run down
- +UltraSafe 2.0 clamps: spark-proof, reverse-polarity protected, manual override for fully dead batteries
- +1.3 lb bare, about 2.2 lb with clamps — lighter than the GB40 and just as pocketable
What to know
- −Same -4°F operating floor as the rest of NOCO's line — no cold advantage over the GB40
- −Still not a V8 or big-diesel pack; a cold 5.7L truck wants the GB70
- −Charging temperature is 32°F to 104°F — you can't top it off in a frozen car
- −60-second boost timeout means power-cycling the unit between attempts
Full review
NOCO's Boost X line is the GB series redrawn around USB-C, and the GBX45 is the compact one. On paper the jump from the GB40 is modest — 1,250A versus 1,000A, a 6.5L gas rating versus 6.0L — but the diesel rating goes from 3.0L to 4.0L, which now covers most of the small turbodiesel crossovers and pickups that the GB40 technically excludes. The 'UltraSafe 2.0' label is NOCO's second-generation clamp electronics: same spark-proof, reverse-polarity-proof behavior as before, with revised thermal and power management the company credits for longer pack life.
The reason to actually buy it over the GB40 is the port. The GB40's micro-USB input takes most of a day to refill the pack from a wall brick; the GBX45's USB-C takes 60W in and refills a 31Wh cell in about 48 minutes, and NOCO's '0% to boost in 5 minutes' claim means that if you find it flat, a few minutes on the charger buys you an attempt. The same port pushes 60W out, so it will charge a laptop — something no jump starter at this price did a few years ago. The 100-lumen light is unchanged, and there's a 12V output the GB40 lacks.
What hasn't changed is the cold math. NOCO rates the GBX45 to the same -4°F as the GB40, and it can't recharge below freezing, so it needs to live in the cabin like every lithium pack. And 1,250A is not a truck number: a cold V8 with a tired battery is still GB70 territory. If you drive a four- or six-cylinder car and you'll appreciate the fast charging, this is the compact NOCO to buy now; if the GB40 is $30 cheaper the day you look, it's still a perfectly good answer.
Best for: The commuter-car buyer who'd pick the GB40 but wants USB-C fast charging, a small-diesel rating, and a bit more cold-morning margin.
Specifications
| Peak amps | 1,250A |
|---|---|
| Engine rating | Gas up to 6.5L / diesel up to 4.0L |
| Battery | 31Wh lithium-ion, 12V systems only |
| Ports | USB-C PD 60W in/out, USB-A out (2.1A), 12V out |
| Flashlight | 100 lumens, multi-mode incl. SOS and strobe |
| Safety | UltraSafe 2.0 — spark-proof, reverse polarity, over-charge, short-circuit; manual override |
| Operating temp | -4°F to 122°F (-20°C to 50°C); charges at 32°F to 104°F |
| Ingress rating | IP65 (ports closed) |
| Recharge | ~48 minutes at 60W USB-C; 0% to boost-ready in 5 minutes |
| Weight | 1.3 lb bare, ~2.2 lb with clamps |
| Warranty | 1 year |
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~$115 typical price
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