Interstate-McBee M-3931623 Valve Tappet – 89–98 5.9L Cummins (12-Valve)

OEM-style aftermarket valve tappet (lifter) engineered to match Cummins specifications for 1989–1998 5.9L Cummins 12-valve (6BT) applications. Commonly used across B-Series engines and select industrial platforms. Designed for consistent lash control, stable valve actuation, and long service life.

• Direct replacement: Built to OEM form, fit, and function for reliable drop-in service.
• Hardened wear surface: Resists scuffing and premature wear during high-load operation.
• Sold individually: Order 12 for a complete 6BT (5.9L) set; 8 for 4BT (3.9L).
• Aftermarket value: Interstate-McBee quality at a fraction of genuine OEM pricing.

Specifications

*Always verify supersessions and substitutions by ESN.

What’s Included

• (1) Interstate-McBee valve tappet (M-3931623)

Vehicle Fitment

For best results, confirm by engine serial number (ESN) before ordering.

• Dodge Ram 2500/3500 – 5.9L Cummins 12V (6BT)
  • 1989–1993 D/W 250–350 (5.9L 12V)
  • 1994–1998 Ram 2500/3500 (5.9L 12V)
• Industrial/Commercial B-Series: 3.9L 4BT; select 8.3L C-Series (6CT/ISC/ISL) (varies by ESN)

Install Notes

• Replace tappets whenever installing a new camshaft; do not reuse worn lifters on a new cam.
• Pre-lube tappet faces and follow factory cam/tappet break-in procedure.
• Set valve lash to spec and recheck after initial heat cycle.

Warranty

Covered by Interstate-McBee’s manufacturer warranty for new engine components. Contact us for terms and coverage details.

Cross-Reference & Compatibility

Interchanges with Cummins 3931623 and superseded numbers 3281508, 3925031, 3907240, 3901787. Application across 4BT/6BT/ISB and select 6CT/ISC/ISL platforms varies by ESN.

Why Buy From CPP Diesel

• ESN-verified fitment support from real diesel techs
• Fast shipping, easy returns, and stocked B-Series parts
• One-stop timing & valvetrain solutions to complete the job

FAQ