2002 Dodge Ram 1500 5.9 Engine for Sale | OEM Mopar Magnum V8 (360 cu in)

Description

Engine Background

The 5.9 Magnum is the V8 that built the second-generation Dodge Ram’s reputation. From 1994 through 2003, this engine powered the half-ton, three-quarter-ton, and one-ton Ram pickups, the Durango full-size SUV, and the Dakota R/T performance truck. Producing 245 hp and 335 lb-ft of torque from 360 cubic inches, it delivered the V8 grunt that made the Ram a serious work truck and a credible alternative to Ford and Chevy half-tons of the same era.

Internally, the 5.9 Magnum is the modernized version of Chrysler’s LA-series small block V8 that traces back to 1964. The Magnum upgrades over the older 360 LA include redesigned cylinder heads with significantly improved port flow, sequential multi-point fuel injection (SMPI) replacing the carburetor, a hydraulic roller camshaft for better high-rpm breathing and lower friction, and a one-piece rear main seal that eliminates the chronic leak point of older LA engines.

Why Ram Owners Choose a Used 5.9 Magnum Over a Reman

Used 5.9 Magnum availability is excellent because over a million were built between 1994 and 2003. A clean used unit from a low-mileage donor truck typically costs less than half of a remanufactured long block, while delivering comparable service life when properly inspected and tested. For Ram owners doing a budget-conscious engine replacement, a verified used 5.9 is the smart choice.

When Replacement Becomes Necessary

• Knock or rattle under load, rod or main bearing wear on high-mileage units
• Blue smoke on startup, valve seal wear (a known 5.9 Magnum issue past 150,000 miles)
• Loss of compression on one or more cylinders, head gasket or ring wear
• Coolant in oil or oil in coolant, head gasket or intake manifold gasket failure
• Excessive timing chain noise on cold start, timing chain stretch
• Low oil pressure on a warm engine, main or cam bearing wear
• Misfire codes that move between cylinders, intake manifold plenum gasket leak (known issue)

Known Issues We Document Before Shipping

• Plenum gasket condition, the most common Mopar Magnum vacuum leak source. The intake manifold plenum gasket fails on high-mileage 5.9 Magnums, causing misfire codes that move between cylinders, rough idle, and reduced fuel economy. We specifically assess plenum gasket condition before shipping.
• Valve seal condition: commonly worn on units past 150,000 miles. Symptom is blue smoke on startup that clears after warmup. We inspect valve cover internal condition for oil burning indicators.
• Timing chain stretch on high-mileage units: timing chain rattle on cold start is the primary indicator. We listen for chain noise where accessible during pre-ship inspection.
• Hydraulic roller lifter operation: the Magnum-generation 5.9 uses hydraulic roller lifters, a significant improvement over the LA-generation flat-tappet lifters. Lifter operation should be quiet and consistent. We inspect for lifter tick or sticking lifters during pre-ship inspection.
• Block casting numbers and date code: for restoration-grade Ram or Durango buyers, casting numbers matter. We document casting numbers and date codes where determinable.

What Ships and What Does Not

Direct-Fit Vehicle Applications

Used OEM Versus Reman

For a 1994 to 2003 Dodge Ram 1500, 2500, 3500, Durango, or Dakota R/T with a worn 5.9 Magnum, a documented used unit with plenum gasket condition assessed and compression results uniform is the cost-effective replacement path. A reman 5.9 Magnum long block typically runs $3,500 to $5,500 from established Mopar specialty shops. A clean used 5.9 with verified compression and known service history typically delivers comparable service life at significantly lower cost. For restoration-grade Ram or Dakota R/T applications, used OEM with documented casting numbers is preferred over reman.

Inspection Workflow

• Compression test logged across all 8 cylinders with uniformity reported
• Year and donor application documented (Ram 1500, 2500, 3500, Durango, or Dakota R/T)
• Block casting numbers documented where available
• Plenum gasket condition specifically assessed (the Magnum signature failure mode)
• Hydraulic roller lifter operation evaluated
• Timing chain rattle assessed at cold start where accessible
• Valve cover internal condition inspected for oil burning indicators
• External oil leak survey at valve covers, timing cover, oil pan, rear main seal

Pre-Purchase Buyer Notes

• Plan a plenum gasket service at installation regardless of donor history: the plenum gasket is the Magnum’s signature failure mode. Aftermarket aluminum plenum plates with improved gaskets are inexpensive and address the issue permanently.
• Replace the intake manifold gaskets at installation: factory plastic intake gaskets degrade with heat cycling. Multi-layer steel gaskets are an inexpensive upgrade.
• Inspect or refresh the timing chain on high-mileage units: timing chain stretch is a known issue past 150,000 miles. Refreshing while the engine is out is cheap insurance.
• Plan valve cover gasket replacement: aged valve cover gaskets leak on high-mileage Magnums. Inexpensive components.
• Match donor application to receiving chassis: a Ram 1500 5.9 and a Ram 2500/3500 5.9 are the same engine but supporting accessories (exhaust manifolds, motor mounts, transmission pairing) may differ. We document donor application on every order.

Why Buy From Part Nests

• Year and donor application documented before payment
• Block casting numbers documented where available
• Plenum gasket condition specifically assessed (Magnum signature failure mode)
• Hydraulic roller lifter operation evaluated
• Timing chain noise assessed where accessible
• All 8 cylinders compression-tested with uniformity reported
• No core return required
• Free freight delivery to every state
• 15 day replacement warranty against internal defects
• Call (240) 306-7051 to speak with someone who knows 5.9 Magnum plenum gasket service, Ram 1500 versus 2500/3500 application differences, and Dakota R/T versus standard Ram tuning