GOOLOO GT4000S vs HULKMAN Alpha85S
HULKMAN Alpha85S
The short answer
GOOLOO GT4000S comes out ahead overall with 7.3/10 against 6.5/10 for the HULKMAN Alpha85S. GOOLOO GT4000S is stronger on starting power, versatility and value. HULKMAN Alpha85S is stronger on battery capacity & standby, build quality & durability and battery safety & sustainability. At current verified prices, the GOOLOO GT4000S costs about $200.03 less.
- Choose the GOOLOO GT4000S if: Diesel pickup owners on a budget who want a light 4,000A pack and can keep it topped up and warm.
- Choose the HULKMAN Alpha85S if: Drivers in sub-zero climates with gas half-ton trucks or SUVs (not HD diesels) who want automatic cell pre-heat.
Scores by criterion
| Criterion | GOOLOO GT4000S | HULKMAN Alpha85S |
|---|---|---|
| Starting Power | 7.54,000A; Outdoor Life recommends it for 3/4-ton diesels; diesel rating conflicts between 8L and 10L | 6.52,000A; failed AutoGuide's 6.5L diesel test after two cranks; fine for gas (TechGearLab) |
| Battery Capacity & Standby | 6.0No published or measured Wh; -4°F floor; 3-month top-up advised | 7.074 Wh unmeasured; -40°F floor is claim-only |
| Ease of Use & Safety Features | 7.5SuperSafe protections, PopSci's Best design, 2.3 lb | 7.5Pre-heat and READY indicator are claimed features; 3.3-inch display |
| Build Quality & Durability | 6.5IP65; some anecdotal reports of units that stopped charging | 7.0IP65 and 2-year guarantee; overheated in AutoGuide's testing |
| Versatility | 7.5100W two-way USB-C PD | 6.565W USB-C; no compressor |
| Battery Safety & Sustainability | 5.0Li-polymer; no certifications named on the product page | 6.0Li-polymer; no UL certification stated |
| Value | 8.8About $100 for a diesel-capable pack recommended by independent outlets | 5.0$300 for a 2,000A pack |
Specifications
| Spec | GOOLOO GT4000S | HULKMAN Alpha85S |
|---|---|---|
| Peak Current | 4,000 A | 2,000 A |
| Max Gas Engine (rated) | — | 8.5 L |
| Max Diesel Engine (rated) | — | 6 L |
| Battery Chemistry | Lithium polymer | Lithium polymer |
| Rated Capacity | — | 74 Wh |
| Weight | 2.3 lb | 3.6 lb |
| Built-in Air Compressor | No | No |
| Max USB Output | 100 W | 65 W |
| Water/Dust Rating | IP65 | IP65 |
| Min Operating Temperature (rated) | -4 °F | -40 °F |
| Automatic Cell Preheat for Extreme Cold | No | Yes |
GOOLOO GT4000S
Pros
- Very low price for 4,000A
- Light at 2.3 lb
- IP65
- 100W USB-C power delivery
- Outdoor Life's pick for diesel trucks
Cons
- Conflicting engine ratings on the maker's page
- No Wh figure or certifications published
- FAQ advises recharging every 3 months
- Some owners report units that stopped charging
A sensible budget pick for diesel pickups if you keep it topped up and warm. It trades documentation and certainty for price.
Full GOOLOO GT4000S review →HULKMAN Alpha85S
Pros
- Automatic cell pre-heat
- TechGearLab scored it 80 on gas vehicles
- 3.6 lb and IP65
- 65W USB output
Cons
- Failed to start a 6.5L diesel in AutoGuide's test
- Cold rating untested independently
- Expensive
- No carrying case
- Engine ratings differ between listings
A niche pick for gas half-tons and SUVs in very cold places. Diesel owners should choose the NOCO, WOLFBOX or Clore.
Full HULKMAN Alpha85S review →Both products are part of our guide The Best Jump Starters for Cold Weather & Diesel Trucks of 2026, where you can see every pick, how we score and current prices from each retailer.