NOCO GB40 vs GB70: Which Jump Starter Do You Need?
2 lessons in this series, 5 min in total
- How Long Does a NOCO GB40 or GB70 Take to Charge? 2 min read
- NOCO GB40 vs GB70: Which Jump Starter Do You Need? 3 min read
Every figure here comes from NOCO’s data sheets and user guides for both models, and we note where those documents disagree. More on how we research.
GB40 vs GB70: the numbers that differ
| Spec | GB40 | GB70 |
|---|---|---|
| Peak current | 1000A | 2000A |
| Gas engines | Up to 6.0L | Up to 8.0L |
| Diesel engines | Up to 3.0L | Up to 6.0L |
| Battery, rated jump starts | 24 Wh, up to 20 | 56 Wh, up to 40 |
| Weight with clamps | 2.4 lb (1.1 kg) | 5 lb (2.3 kg) |
| 12V accessory output | None (12V OUT is for the clamps) | 12V, 15A |
Other differences in the same documents:
- Bare unit: 1.65 lb (0.7 kg) for the GB40 and 4 lb (1.8 kg) for the GB70.
- Size: 6.7 x 3.2 x 1.7 in (17 x 8.1 x 4.3 cm) against 8.6 x 6 x 2.5 in (21.8 x 15.2 x 6.4 cm) per the user guides, so the GB70 is a trunk-size pack. The data sheet drawings show about 6.6 x 3.2 x 1.7 in (16.8 x 8.1 x 4.3 cm) and 8.8 x 6.0 x 2.7 in (22.4 x 15.2 x 6.9 cm), so treat sizes as approximate.
- Phone recharges: up to 4 against up to 6.
- LED light: 100 against 400 lumens, both with 7 modes.
- GB40 clamp cable: 23 in (58 cm) on the data sheet drawing.
- Recharge: 3 hours against 7 on a 2A source, and only the GB70 has a 12V fast-charge input. See how long the GB40 and GB70 take to charge.
What the extra 1000 amps covers
The biggest gap is engine size. For gas engines, the GB70’s rating goes from 6.0L to 8.0L, and for diesels it doubles, from 3.0L to 6.0L. NOCO’s ratings treat diesels as the harder job: the GB40 is rated for gas engines twice the size of the diesels it covers.
The engine rating is the number to match to your vehicle. Find your engine size and fuel type, then pick the pack whose rating covers it.
The battery explains the gaps in rated jump starts and phone recharges listed above. At 56 Wh, the GB70’s battery is more than twice the size of the GB40’s 24 Wh, which is why NOCO rates it for more of both per charge. Those are “up to” ratings, and the real count varies with the engine, the temperature and how drained the car’s battery is.
What’s the same on both
NOCO’s guides and data sheets give both units the same basic rules and protections:
- 12-volt lead-acid batteries only. The data sheets list wet, gel, MF (maintenance-free), EFB and AGM types, and the guides say not to use either pack on any other type, which rules out lithium car batteries.
- Spark-proof connection and reverse-polarity protection.
- 2-volt floor. Both jump batteries down to 2 volts, and below that a Manual Override button forces power on. See what Manual Override switches off.
- Five attempts, then rest. Both guides allow no more than five jump-start attempts in a row within 15 minutes, then a 15-minute rest. See how to use a jump starter safely.
- USB in and out at 5V 2.1A.
- IP65 housing with the ports closed.
- Operating range of -4°F to 122°F (-20°C to 50°C).
- 1-year limited warranty in the US.
Who should buy which
- Gas engines up to 6.0L in sedans, hatchbacks, crossovers and small SUVs: the GB40.
- Diesel engines over 3.0L, up to 6.0L: the GB70, because the GB40 isn’t rated for them.
- Gas engines over 6.0L, up to 8.0L: the GB70.
- 12V gear powered from the pack: the GB70, whose 12V port is rated up to 15A. Check that your device draws 15A or less.
- The lightest, quickest-charging option for one car: the GB40.
- Helping other drivers, or one pack for several vehicles: the GB70, for its larger battery and wider engine range.
Not sure of your engine size? Check your owner’s manual. The GB70 isn’t overkill for a regular car in terms of compatibility, since neither guide sets a minimum engine size, but it costs you weight, size, recharge time and money.
The GB40 suits everyday cars and easy carrying, as long as you don’t need a diesel rating past 3.0L or a 12V outlet.
NOCO Boost Plus GB40
A compact 12V lithium jump starter. NOCO rates it at 1000A peak, for gas engines up to 6.0L (366 cu in) and diesel engines up to 3.0L.
Key specs
- 1000A peak
- Gas engines up to 6.0L, diesel up to 3.0L
- Compact 12V lithium
Paid link
View on Amazon (opens in a new tab)The GB70 suits big gas engines, diesels and anyone who wants more starts per charge, at the cost of a heavier pack.
NOCO Boost HD GB70
NOCO's larger lithium jump starter: 2000A peak, rated for gas engines up to 8.0L and diesel engines up to 6.0L.
Key specs
- 2000A peak
- Gas engines up to 8.0L, diesel up to 6.0L
- 12V lithium
Paid link
View on Amazon (opens in a new tab)Check your engine size, then read how many amps you need in a jump starter and pick the rating that covers it. Buying one as a gift? Gifts for new drivers covers what to do before you wrap it.
