Cummins 3283339 — Genuine Cylinder Head Gasket (+.020" Thick) for 5.9L 12-Valve

MPN: 3283339  |  Also Known As: head gasket, thick/oversize gasket  |  Size: +.020" (0.50 mm) oversize

Genuine Cummins cylinder head gasket for 1989–1998 5.9L 12-valve (6BT) engines. This +.020" thickness gasket is commonly chosen after head/block resurfacing or when piston protrusion measurements require a thicker gasket to maintain correct quench and compression. 1 per engine.

Features & Benefits

• OE sealing performance for high cylinder pressures and daily-duty reliability.
• +.020" (0.50 mm) oversize for engines that need extra thickness after machining or to meet spec based on piston protrusion.
• Drop-in fit on 5.9L 12V (1989–1998) when the oversize is specified by measurement.
• Prevents coolant/oil cross-leakage and maintains stable compression.
• Genuine Cummins material stack and fire-ring construction for durability.

Verified Fitment (Automotive)

Industrial/Off-Highway: B5.9 / 6B series 12-valve applications—verify by ESN before ordering.

Specifications

• Type: Cylinder head gasket (fire-ring, multi-layer composite/steel as OE design)
• Thickness: +.020" (0.50 mm) oversize
• OE Part Number: 3283339
• Engine Family: Cummins B5.9 / 6BT (12-valve)
• Quantity Required: 1 per engine (sold individually)

Often Paired With

• Head fasteners: new OE head bolts or performance head studs (follow torque specs & sequence)
• Top-end gasket set: intake/exhaust manifold, valve cover, injector seal kits
• Coolant & oil: refresh after repair; bleed air and recheck levels after heat cycle

What’s In The Box

• (1) Genuine Cummins Cylinder Head Gasket (+.020") — 3283339

Installation Tips

• Measure piston protrusion and select gasket thickness accordingly (+.020" used only when specified).
• Verify head/block flatness and surface finish; clean threads and chase as needed.
• Use new bolts or quality studs; follow the OEM torque pattern, angles, and lube guidance.
• Recheck coolant/oil levels and inspect for leaks after initial heat cycle.

FAQ

WILL THIS FIT MY 1989–1998 5.9L 12-VALVE CUMMINS?

Yes—3283339 is a +.020" thick head gasket for 5.9L 12-valve (1989–1998). Select thickness by measurement, not guesswork.

WHAT DOES +.020" (0.50 MM) OVERSIZE MEAN?

It’s a thicker-than-standard gasket used when piston protrusion or machining requires more thickness to maintain proper quench/compression.

CAN I USE THIS ON A 24-VALVE OR COMMON-RAIL ENGINE?

No—this listing targets 12-valve engines. 24-valve (1998.5–2002) and common-rail (2003+) use different gaskets.

DO I NEED NEW HEAD BOLTS OR STUDS?

Yes—always replace torque-to-yield bolts or upgrade to studs. Follow the correct torque sequence and angles.

DOES THIS GASKET CHANGE COMPRESSION?

Thickness affects quench and effective compression height. Use +.020" only when required by protrusion measurement or post-machining service specs.