NOCO Boost X GBX55 jump starter review

Overview

The NOCO Boost X GBX55 is a premium portable jump starter aimed at drivers who need more capacity than a compact car-focused pack provides. It ranks #9 in our list of the top 10 best-selling portable jump starters on Amazon UK, with an 8.5/10 score and our Best for motorhomes award. Its 1,750A peak output and claimed compatibility with petrol engines up to 7.5 litres and diesel engines up to 5.0 litres make it a stronger match for vans, motorhomes and larger cars than the NOCO Boost GB40. The GB70 ranks higher overall and is another option for larger vehicles; the GBX55’s distinction is its 60W USB-C charging and power-bank capability.

Features and specification

The GBX55 is a 12V lithium-ion unit measuring 23.2 × 16.1 × 10cm and weighing 1.53kg according to the supplied specifications. NOCO claims up to nine starts per charge, though results will depend on the vehicle, battery condition and use. Its spark-proof and reverse-polarity protections are intended to reduce connection mistakes, but users should still follow the instructions and confirm the clamps are correctly attached.

USB-C Power Delivery works in both directions, so the pack can charge devices such as phones, tablets and compatible laptops. The listing says it can recharge in as little as 1.2 hours with a 60W charger, which is not included; a standard lower-powered charger may take longer. A 200-lumen torch has seven modes, including SOS and strobe. There is no display for checking battery status, so drivers who want a clear readout may prefer the Ring UltraBoost 1500A. The box includes jump leads, a USB-C cable and a storage bag, and the stated warranty is one year.

What owners say

Owner reports are encouraging on starting power and charge retention. Motorhome and van owners describe successful starts on diesel vehicles, while others say the pack has remained useful after months in storage or delivered several starts between charges. Review themes also praise straightforward operation, convenient storage and the torch. These are individual experiences, not a guarantee of performance in every situation.

There are some durability and reliability concerns. A few owners report trouble recharging a faulty unit, and complaints include breakage to the plastic around the clamps. Independent product-review listings also mention occasional early defects and clamp-plastic damage. At this price tier, those reports are worth considering alongside the generally positive feedback.

Who should buy it

The GBX55 is a sensible shortlist choice for motorhome, van and larger-car owners who want substantial starting capacity plus USB-C power delivery in one pack. Its charge-retention reports may also appeal to drivers keeping an emergency booster in a vehicle that sits unused for long periods. The fast recharge claim depends on having a suitable 60W charger, so allow for a slower top-up if you only have a basic USB supply.

For a small petrol car, this is likely more capacity and expense than necessary; consider a smaller option such as the NOCO GB20 instead. Skip it if a battery-status display is important, or if you want a longer warranty. Overall, the GBX55 is a capable premium choice for larger vehicles, but its size, cost and occasional durability complaints make it less compelling for everyday small-car use.