null AW-17220743903, GT-K4ZB5X3V
CUMMINS

CUMMINS 3957912 OEM VALVE STEM SEAL (TOP HAT STYLE) – 5.9L 12V 6BT (1989–1998)

(No reviews yet) Write a Review
SKU:
CUM3957912
MPN:
3957912
Shipping:
Calculated at Checkout
  • CUMMINS 3957912 OEM VALVE STEM SEAL (TOP HAT STYLE) – 5.9L 12V 6BT (1989–1998)
  • CUMMINS 3957912 OEM VALVE STEM SEAL (TOP HAT STYLE) – 5.9L 12V 6BT (1989–1998)
  • CUMMINS 3957912 OEM VALVE STEM SEAL (TOP HAT STYLE) – 5.9L 12V 6BT (1989–1998)
$11.90

Description

Genuine Cummins

Cummins 3957912 — Valve Stem Seal (Top Hat Style) for 5.9L 12V 6BT

MPN: 3957912  |  Also Known As: valve stem oil seal, “top hat” seal  |  Qty Required: 12 per engine (sold individually)

Why This Part

  • OE sealing to control oil at the valve stem and reduce oil consumption.
  • Top-hat design helps prevent the seal from riding up under boost.
  • Direct-fit for 5.9L 12V 6BT with top-hat style seats/retainers (see notes).
  • Sold individually so you can order exactly 12 for a complete set.
OE Fit Top Hat Style 12 Per Engine

Quick Specs

Type Valve stem seal (intake/exhaust), top-hat style
OE Part # 3957912
Engine 5.9L 12V Cummins 6BT (automotive), plus 4BT/6BT industrial—verify by ESN
Qty Required 12 per engine (sold individually)

Verified Fitment (Automotive)

Year RangeEngineChassis
1989–1993 5.9L 12V 6BT D/W 250/350
1994–1998 5.9L 12V 6BT Ram 2500/3500

Industrial/Off-Highway: Common on 4BT/6BT (B-Series). Always confirm by Engine Serial Number (ESN).

Compatibility Notes: Many OEM 12V heads originally used an older seal design. Top-hat seals may require updated retainers/rotators or light machining. If your head already has top-hat seats, these are direct-fit. Always verify by head casting and component style.

Often Paired With

  • Set of 12 seals (order quantity 12 for a complete engine)
  • Valve retainers/rotators (upgrade when needed): 3957913 (retainer), 3957914 (rotator)
  • Valve collets/locks: 3900250
  • Valve springs/valves if wear is present

What’s In The Box

  • (1) Genuine Cummins Valve Stem Seal (3957912)
  • Sold individually; order 12 for a complete engine set.

Install Tips

  • Use proper valve-spring compressor tools; protect valve stems during install.
  • Lightly oil the seal lip; press squarely onto the guide until fully seated.
  • If converting from old-style seals, confirm retainer/rotator compatibility or machine per shop guidance.

FAQ

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

Yes—3957912 is the OE top-hat style valve stem seal for 5.9L 12V 6BT applications. Verify head/seal style before ordering.

HOW MANY DO I NEED?

Order 12 seals for a complete engine (one per valve). Sold individually.

DO THESE FIT BOTH INTAKE AND EXHAUST?

They’re commonly used on both when the cylinder head is set up for top-hat style seals. If your head is still the early style, an update may be required.

DO I NEED TO MACHINE THE HEAD?

Only if you’re converting from the original early seal style. Many aftermarket or updated heads already accept top-hat seals.

IS THIS A GENUINE CUMMINS PART?

Yes—OE Cummins 3957912. We also carry quality aftermarket equivalents if desired.

View AllClose

Additional Information

Vehicle Year:
1989-1998
Vehicle Make:
DODGE
ENGINE:
5.9L CUMMINS
View AllClose

0 Reviews

View AllClose