NOCO GBX45
Boost X 1250A · 31Wh
Gas engines up to 6.5L; diesel up to 4.0L
Check exact product and conditionNOCO Boost X Jump Starters: GBX45, GBX55, GBX75 & GBX155
NOCO Boost X portable lithium jump starters are intended for emergency starting of compatible 12-volt vehicle batteries. The GBX45, GBX55, GBX75 and GBX155 vary by peak starting current, manufacturer-listed gasoline and diesel engine size, and internal battery capacity. The most powerful model is not automatically the correct choice for every vehicle or battery system. This guide compares the four models and identifies two related accessories offered by UsedRVParts.
NOCO Boost X size and starting-power chart
| Model | Peak starting current | Gasoline rating | Diesel rating | Internal battery |
|---|---|---|---|---|
| GBX45 | 1,250A | Up to 6.5L | Up to 4.0L | 31Wh |
| GBX55 | 1,750A | Up to 7.5L | Up to 5.0L | 46Wh |
| GBX75 | 2,500A | Up to 8.5L | Up to 6.5L | 74Wh |
| GBX155 | 4,250A | Up to 10.0L | Up to 8.0L | 99Wh |
These are NOCO's published maximum engine displacement ratings for compatible 12V gasoline and diesel starting applications. They are not a promise of successful starting in every circumstance: cold weather, poor battery condition, engine condition and electrical faults can affect the required starting power. The internal Wh figures describe the jump starter's own lithium battery capacity, not the battery capacity of the vehicle.
For smaller enginesGBX45 supplies 1,250A of peak power, with a 31Wh internal battery and NOCO-listed engine applications up to 6.5L gasoline and 4.0L diesel. GBX55 increases the peak current to 1,750A and covers up to 7.5L gasoline and 5.0L diesel.
For larger starting loadsGBX75 provides 2,500A, with published engine ratings up to 8.5L gasoline and 6.5L diesel. GBX155 is the 4,250A option with a 99Wh internal battery and published ratings up to 10.0L gasoline and 8.0L diesel.
What to check before selecting a portable jump starter
- Confirm battery voltage. These four Boost X models are intended for 12V starting systems. Do not connect one directly to a 24V starting system, a high-voltage hybrid/EV traction system or an application outside NOCO's instructions.
- Check engine displacement and fuel type. Compare the actual gasoline or diesel engine size with the model-specific published limit. The vehicle badge or body size does not establish engine compatibility.
- Consider the starting conditions. Cold temperatures, battery damage and engine mechanical problems can increase starting demand. A portable booster does not diagnose or repair the underlying fault.
- Follow the clamp connection procedure. NOCO's UltraSafe protection includes safeguards against common connection errors, but the battery terminals and vehicle manufacturer's procedures must still be followed.
- Keep the booster charged. NOCO specifies USB-C Power Delivery recharging on these models. Recharging time depends on the charger and cable used; a lower-output USB supply can take longer.
- Inspect accessories separately. A protective case is a storage accessory and a USB-C charger restores the Boost X's charge. Neither increases the starter's peak output or turns it into a 12V battery charger for maintaining the vehicle's battery.
Using Manual Override: Certain NOCO jump-starting procedures allow a manual override for severely discharged batteries. The manufacturer's warnings state that override mode disables important safety protections. Follow the exact manual and never use it to bypass uncertain polarity, a damaged battery or a non-12V system.
Which NOCO accessories go with these models?
U65 is a separate 65-watt USB-C AC power supply listed for GBX45, GBX55, GBX75 and GBX155. It accepts 100–240V AC and includes interchangeable mains plug adapters. It charges the jump starter's internal battery; it is not a vehicle charging or maintenance unit.
GBC101 is a semi-rigid EVA storage case designed specifically for GBX45. Its model-specific fit should not be assumed to accommodate the larger GBX55, GBX75 or GBX155 jump starters.
Shop exact NOCO Boost X models
These product cards link to the corresponding UsedRVParts.ca listings. Check current condition and availability before ordering. The store sells brand-new as well as used RV, towing and marine parts; eligible used items may be viewed or picked up in Kelowna by appointment.
NOCO GBX55
Boost X 1750A · 46Wh
Gas engines up to 7.5L; diesel up to 5.0L
Check exact product and condition
NOCO GBX75
Boost X 2500A · 74Wh
Gas engines up to 8.5L; diesel up to 6.5L
Check exact product and condition
NOCO GBX155
Boost X 4250A · 99Wh
Gas engines up to 10.0L; diesel up to 8.0L
Check exact product and conditionCompatible charger and storage case listings
NOCO U65
65W USB-C AC charging adapter
100–240V AC, compatible with GBX45, GBX55, GBX75 and GBX155
View matching accessory
NOCO GBC101
Protective EVA storage case
Designed specifically for the GBX45 jump starter
View matching accessoryRelated battery charging equipment
If you need continuous charging and maintenance rather than emergency starting, see our NOCO GEN5X and GENPRO10X marine battery-charger comparison. Those are dedicated onboard chargers with independently controlled charging banks, not portable jump starters.
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