What is the spark plug gap for a 3.7 V6?
The spark plug gap for most 3.7L Chrysler/Jeep V6 engines is 0.040 inches (1.0 mm).
The 3.7L PowerTech V6 is used across a range of Mopar models, including Jeep Grand Cherokee, Liberty, and Dodge Durango. While many plugs come pre-gapped, it's important to verify or set the gap to the factory specification when installing replacements, and to consult your exact model-year service information for any exceptions.
Specification and installation basics
Understanding where the 0.040 inch figure fits in helps you service plugs correctly and avoid misfires or degraded fuel economy.
Plug types and gap considerations
Most replacements for the 3.7L V6 use copper, platinum, or iridium plugs. The factory specification for these engines is commonly a 0.040 inch gap. If you install plugs with a different pre-gap, recheck and adjust to 0.040 inches before installation.
To verify and set the gap during service, follow these steps:
- Identify your engine model year and confirm the recommended gap in the owner's manual or service bulletin.
- Inspect the replacement plugs to ensure they are correct heat range and are pre-gapped; if not, use a spark plug gap tool to set to 0.040 inches (1.0 mm).
- Carefully thread the plug by hand to avoid cross-threading, then tighten to the specified torque from the manual.
- After installation, recheck the gap if the plug was adjusted after initial seating to ensure it remains at 0.040 inches.
Maintaining the proper gap helps ensure consistent ignition timing, smoother idle, and better fuel economy on a 3.7L V6.
Summary
For the 3.7L V6, the standard spark plug gap is typically 0.040 inches (1.0 mm). Always verify this specification against your specific vehicle’s manual and plug type, as there can be minor variations by model year or replacement plug brand.
