Best Jump Starter for a 5.7L HEMI (Ram / Charger / Challenger / Durango)

The 5.7L HEMI is one of the longest-running V8 engines on the road, deployed in the Ram 1500, Charger, Challenger, Durango, Grand Cherokee, and Wrangler Rubicon 392 (in its larger 6.4L sibling). HEMI owners ask about jump starters more than most V8 owners because the HEMI's eTorque mild-hybrid variant adds a second battery and changes the conventional jump procedure. The right portable handles both.

The Quick Answer

The Fanttik T8 APEX is the right portable jump starter for any 5.7L HEMI vehicle. The HEMI's typical cranking pull lands at 550-800A — well inside the T8 APEX's 2,000A peak. The eTorque-equipped HEMI in the Ram 1500 adds a 48V battery on top of the conventional 12V, but jump starting still targets the 12V battery, and the procedure is unchanged from a non-eTorque HEMI.

Why the HEMI Spans So Many Vehicles

The 5.7L Hemi is the workhorse V8 of the Stellantis (Chrysler/Dodge/Ram/Jeep) lineup. The same basic engine appears in pickups, full-size sedans, performance coupes, and 3-row SUVs. Cranking-current characteristics differ slightly by vehicle weight, alternator load, and accessory draw, but they're close enough that one jump starter sizing covers all of them.

The Specs You Need to Know

eTorque HEMI: What the Jump Procedure Changes

Ram 1500 eTorque trucks add a 48V lithium battery that powers regenerative-braking-style engine restarts. The 48V system is separate from the conventional 12V starter, which means a flat 12V battery still needs a conventional jump. The 48V battery does not crank the engine and is not jumpable from a 12V portable. The T8 APEX connects to the 12V battery exactly like on a non-eTorque HEMI.

How to Jump a 5.7 HEMI with the T8 APEX

1. Open the hood. Locate the 12V battery — on the Ram 1500 and Durango, it's on the passenger side. On the Charger and Challenger, the underhood battery is on the driver side near the strut tower.
2. Red clamp to positive. Black clamp to a chassis ground bolt or the negative post.
3. Wait for green ready light. HEMI engines crank reliably on the first try.
4. If the indicator is amber, hold force-start. This is rare on a HEMI unless the 12V is deeply discharged.
5. Drive for 20-30 minutes to recharge the 12V. On eTorque trucks, the 48V system will also begin to balance as the engine runs.

What to Watch Out For

• Wrangler Rubicon 392 owners — the 6.4L SRT HEMI is at the upper end of what the T8 APEX is sized for. Cold-weather cranking on a 6.4 in subzero temperatures can pull near 850A, leaving margin but not a lot.
• Don't try to jump the eTorque 48V battery. It's not user-serviceable from outside the powertrain.
• Ram 1500 HEMI trucks with the Auxiliary Power Outlet ("APO") will not let you jump from that outlet — it's accessory-only. Use the underhood battery directly.

FAQ

Q: Is the T8 APEX enough for a 6.4L HEMI in a Wrangler 392?
A: Yes, in most conditions. Subzero starts may need force-start mode. Owners doing serious cold-weather work on the 392 should keep the pack inside the cab to maintain its own temperature.

Q: Can the T8 APEX jump a Ram 1500 eTorque?
A: Yes. The jump targets the conventional 12V battery; the 48V system is separate.

Q: How does the HEMI compare to a Cummins for jump-starter sizing?
A: The HEMI pulls roughly one-third of a Cummins 6.7's typical cranking current. A jump starter sized for a Cummins is enormous overkill for any HEMI.

Verdict

The Fanttik T8 APEX 2000A Jump Starter is the right portable for the entire 5.7L HEMI family. It also handles the 6.4L SRT HEMI in the Wrangler 392 and Durango SRT 392, with cold-weather force-start as the backup. One pack covers your entire Stellantis garage.

Related reading: Best jump starter for a Ram 1500 · Jump starter for V8 vs V6 engines · Best jump starter for a 5.3 Vortec V8