How does the battery preheat work?

You activate preheat before a cold start and the pack warms its internal battery so it can deliver full current. GOOLOO rates it for use down to -40°F, though preheat takes some minutes before you crank the engine.

Will it start a diesel truck?

It is built for large gasoline and diesel engines, including trucks and SUVs. Check your engine's displacement against GOOLOO's stated capacity for the GT4000 line before relying on it.

Can I use it as a power bank?

Yes. It has USB output for charging phones and small devices, plus a built-in flashlight for roadside work.

How often should I recharge it?

Recharge it every few months, and top it up before winter, so it is ready when needed. Lithium packs lose charge slowly when stored.

Is it worth it over a regular jump starter?

If you park outside in hard freezing weather, the preheat feature is the reason to choose it. In mild climates a smaller, lighter pack does the same job with less bulk.