Jump starter guide
NOCO Boost X GBX155 4250A 12V Lithium Jump Starter
Gas engines to 10L and diesels to 8.0L, with a 60 W USB-C charger on hand
NOCO rates the GBX155 at 4250 A peak for gas engines to 10 litres and diesels to 8.0 litres, on a 99 Wh pack. The guide's charging table runs from 2.7 hours on a 60 W USB-C PD charger to 64 hours on a 2.5 W one.
Listing checked . Confirm the model, included parts and availability before ordering.
Published specifications
- NOCO: 4250 A peak; gas up to 10 L, diesel up to 8.0 L; 12V lead-acid only
- NOCO: 99 Wh lithium-ion; starts batteries down to 3 V
- Guide: recharge 2.7 h at 60 W, 16 h at 10 W, 64 h at 2.5 W
- Guide: 60-second timeout; max 5 starts in 15 minutes, then 15-minute rest
- NOCO: 5.82 lb; 12.0 x 6.9 x 2.7 in; IP65 with ports closed
- Guide: one-year warranty from purchase, or from serial date without receipt
Fit and limits
Strengths
- Guide publishes a recharge table for four charger sizes
- USB-C in and out up to 60 W, plus a USB-A output
- Warranty still runs from the serial number date if you lose the receipt
Caveats
- Box lists differ: NOCO names a 12V to USB-C cable, the listing a fast charger
- Manual override disables both protections and the 60-second timeout
- Listing's 18-starts-per-charge claim is not in NOCO's documents
What NOCO rates the GBX155 for
NOCO rates the Boost X GBX155 at 4250 amps peak, for gas engines up to 10 litres and diesel engines up to 8.0 litres, on its tech specs and overview pages, and the listing uses the same figures. The guide attached to this listing gives the same 4250 A peak current rating and a 99 watt-hour lithium-ion internal battery, which matches the tech specs page.
The guide says the GBX155 is compatible with 12-volt lead-acid batteries only, and that it is designed to start 12-volt lead-acid batteries down to 3 volts. The guide's regulatory text names Model Number GBX155, as does the listing.
The listing's bullet says the 60-second timer delivers up to 18 jump starts per charge. That count does not appear in the guide pages we read or in the parts of NOCO's pages we read, so it rests on the listing alone; ask NOCO if the number of starts per charge matters to you.
Recharge time depends heavily on the charger
The guide's recharge table spells out how much the charger matters: 64 hours at 2.5 W, 32 hours at 5 W, 16 hours at 10 W and 2.7 hours at 60 W. NOCO's overview page and the listing give the 2.7-hour figure, and the overview says the unit can go from 0% to jump starting in 5 minutes of charge.
The guide says a compatible charger capable of 60 W USB-C Power Delivery 3.0 is required to use fast charging fully, and that the fast charge light comes on when the charge rate exceeds 15 W. It says to charge with the included USB-C cable or the 12V car charger, and that NOCO does not recommend third-party USB-C cables and power adapters.
The unit ships partially charged and must be fully charged before use, according to the guide, which also says to avoid charging for more than a week at a time, that an unused unit will discharge and must be recharged before use, and to disconnect it from power sources when not in use.
What is in the box depends on who you ask
NOCO's tech specs page lists the box as the GBX155 with integrated HD precision battery clamps, a 24-inch USB-C to USB-C cable, a 24-inch 12V to USB-C cable, a microfiber storage bag and safety and warranty information. It lists no wall charger.
The listing's What's in the box block names a USB-C charging cable and a '12V USB-C Fast Charger', along with heavy-duty jumper cable clamps and a microfiber storage bag, and its bullet list leaves the 12V charger out. The guide refers to 'the included USB-C Charge Cable or 12V Car Charger'. None of the three explains how its wording relates to the others.
Check the box on arrival against NOCO's list. If you want the 2.7-hour recharge at home, none of these sources lists a 60 W USB-C wall charger in the box.
The 60-second timeout, the five-starts rule and override
The guide says a 60-second countdown starts as soon as a battery is detected, and once it ends the jump starting function is disabled until the unit is switched off and back on; the power LED turns orange after the timeout. The countdown is disabled in manual override mode.
It sets a duty limit of no more than five consecutive jump starts within a fifteen-minute period, followed by a fifteen-minute rest. The troubleshooting table says that when the unit is too cold or too hot to jump start, only the flashlight is available, and lists codes for a system above 12 V, a failed cell, a charge timeout and back-charging.
For batteries below 3 volts the guide describes a manual override. Its caution says both the spark-proof and reverse polarity protections are disabled, the 60-second timeout is disabled, and the mode uses up to 4250 amps. We do not reproduce the procedure; it is in the guide.
Weight, size, temperature and outputs
The guide and NOCO's tech specs page both give 5.82 pounds (2.64 kg). The listing's product details give 7.01 pounds and do not say whether that includes packaging; NOCO does not comment on the difference.
The guide gives dimensions of 12.0 by 6.9 by 2.7 inches, and the tech specs page gives a height of 6.89 inches, width 12.03 inches and depth 2.72 inches. The listing gives 8.18 by 4.84 by 13.51 inches. The guide's operating range is -20°C to +50°C, charging 0°C to +40°C, and storage -20°C to +50°C with a daily average of 0°C to +25°C.
Outputs are USB-C at up to 20 V and 3 A and USB-A at 5 V, 2.1 A, 10 W, per the guide and the tech specs page, and the listing's comparison table marks a 12V power port. The flashlight is 500 lumens on NOCO's tech specs page, and the housing is rated IP65 with the ports closed.
Warranty: with or without a receipt
The guide attached to this listing gives a one-year limited warranty from the date of purchase, with repair or replacement at NOCO's discretion, subject to its technical support analysis. It is for the original purchaser from NOCO or a NOCO approved reseller or distributor and cannot be transferred.
To claim, the guide says you first obtain a return authorization number from NOCO Support at support@no.co or 1.800.456.6626, then send the product with that number and your receipt, with the purchaser prepaying packaging and shipping. Its Hassle-Free conditions say the year runs from the purchase date with a receipt, or from the serial number date without one.
The guide lists what voids it, including misuse, improper storage, modification, and disassembly or repair by anyone other than NOCO, and excludes normal wear, cosmetic damage and units with a missing serial number. It recommends registering at no.co/register. Check the seller and condition of the offer you select.
Check the current listing
Confirm the model, included parts and availability before ordering.
Primary sources
- NOCO GBX155 user guide and warranty (listing-supplied copy)
- NOCO tech specs page for the GBX155
- NOCO product overview page for the GBX155
Primary sources checked .
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