Dodge 318 Engine for Sale | LA and Magnum 5.2L Small Block V8

About the Dodge 318 Engine

The Dodge 318 is Chrysler’s best-selling V8 engine and one of the most widely used American V8s in automotive history. Introduced in 1967 as the LA (Light A) series small block, it remained in production in evolved form through 2003, a 35-year production run that saw it power virtually every Chrysler, Dodge, and Plymouth vehicle ever built during that era. Where the 340 and 360 got the performance headlines and the 383 and 440 got the muscle car glory, the 318 was the engine that actually kept America moving. It was in police cruisers, taxi fleets, everyday sedans, pickup trucks, cargo vans, and RVs for three and a half decades.

The 318 earned its reputation through two core strengths: durability and reasonable fuel economy. With its 2-barrel carburetor and modest state of tune, it produced 200 to 230 hp, enough for smooth highway performance in a full-size Dodge or a spirited launch in a lighter Dart or Duster, while returning 15 to 16 mpg that most of its big-block contemporaries could not approach. Police agencies across the country chose the 318-powered Dodge Diplomat over comparable Ford and Chevrolet alternatives for its combination of performance and long-term durability.

In 1992, Chrysler introduced the Magnum update: roller lifters replacing flat-tappet units, revised cylinder heads with improved port flow, and sequential multi-port fuel injection replacing carburetors and TBI. The Magnum 318 (sold as the 5.2 Magnum) remained in production through 2003 in the Ram truck lineup and represents the most capable and most durable evolution of this architecture.

Signs You Need a Replacement Engine

• Blue smoke on cold start that clears after warm-up, valve stem seal wear, extremely common on high-mileage LA 318 engines

• Knock under load, rod or main bearing wear on high-mileage units

• Rough idle that worsens when warm, cam lobe wear on flat-tappet LA engines that were run without proper ZDDP oil

• Loss of compression on one or more cylinders, ring wear or scored cylinder walls

• EFI rough idle or hesitation not resolved by basic service on Magnum 318, MAP sensor or idle air control failure

• Oil leaks at front timing cover and valve covers, common on aged Mopar small blocks

Known Problems With This Engine

• Flat-tappet cam lobe wear on LA 318 (pre-1992): The LA 318 uses a flat-tappet camshaft. Modern engine oils are formulated with reduced zinc (ZDDP) for catalytic converter protection, but this makes them inadequate for flat-tappet camshaft lubrication. Any LA 318 that has been run for years on modern low-zinc oil likely has accelerated cam lobe wear. We inspect valvetrain indicators and report before shipping.

• LA vs Magnum head incompatibility: The LA 318 and Magnum 318 use different cylinder heads. The Magnum heads have larger ports and a different intake manifold bolt pattern. They are not directly interchangeable. We document which generation head is on the unit before every order ships.

• 5-bearing crankshaft vs competition: The 318’s 5-bearing crankshaft was entirely adequate for the engine’s power output but limited its response to high-rpm performance modifications compared to engines with more main bearings. For a stock or mild street replacement, this is a non-issue.

• Lean Burn ignition system on 1977 to 1979 LA 318: These years used Chrysler’s problematic Lean Burn electronic ignition that caused reliability issues. We note ignition system configuration on these year-specific units.

• EGR and emissions equipment on late LA units: 1975 and later LA 318s have EGR valves and increasingly complex emissions equipment that can cause surging, rough idle, and fuel economy loss when aged. We note emissions equipment condition on late-model LA units.

FAQs

What liter is a 318 Dodge motor?