Product Description
Interstate-McBee M-3957912 Valve Stem Seal – 89–98 5.9L Cummins (Top-Hat Style)
OEM-style top-hat valve stem seal engineered by Interstate-McBee for the 1989–1998 5.9L Cummins 12-valve plus select 3.9L 4BT B-Series applications. Built for reliable sealing, reduced oil consumption, and long service life at an aftermarket price.
- Direct replacement: Aftermarket equivalent to Cummins 3957912.
- Top-hat design: Stable sealing that resists riding up on the valve stem.
- Durable construction: Quality materials to meet or exceed OEM fit and function.
- Sold individually: Order 12 pcs for a complete 12-valve cylinder head.
Specifications
| Brand | Interstate-McBee |
|---|---|
| Part Number | M-3957912 |
| OEM Reference | Cummins 3957912 |
| Style | Top-hat valve stem oil seal |
| Unit | Each (1 seal) |
| Position | Valve stem (intake & exhaust) |
| Engine Family | Cummins B-Series (4BT/6BT) |
Vehicle Fitment
Verify by engine serial number (ESN) when possible.
- Dodge Ram 2500/3500 – 5.9L Cummins 12-Valve (6BT)
- 1989–1993 (VE pump)
- 1994–1998 (P-pump)
- Industrial/Commercial: 3.9L 4BT B-Series applications (varies by ESN).
Install Notes
- Many OEM heads with original “old-style” seals may require machining to accept top-hat seals; heads already using top-hat seals are typically direct-fit.
- Always follow Cummins service procedures for valve spring removal and seal installation.
- Inspect valve guides; replace any excessively worn components before installing new seals.
What’s Included
- (1) Valve stem oil seal (top-hat style)
Warranty
Interstate-McBee new engine parts carry manufacturer warranty coverage; valve-train components are typically 12 months from date of installation. Contact us for details.
Why Buy From CPP Diesel
- ESN-verified fitment support from real diesel techs
- Fast shipping and hassle-free returns
- Deep B-Series inventory for one-trip checkout
FAQ
Is this the correct seal for 1989–1998 5.9L Cummins 12-valve?Yes, M-3957912 matches Cummins 3957912 and is listed for 1989–1998 5.9L Cummins 12V applications. Verify by ESN for certainty.
How many seals do I need?
One per valve. A 12-valve 5.9L cylinder head uses 12 seals.
Will this fit a 4BT?
Common on many 3.9L 4BT B-Series applications. Confirm by ESN and cylinder head style before ordering.
Do I have to machine my head for top-hat seals?
Some OEM heads with the original seal design require machining for top-hat style. Heads already set up for top-hat seals are typically drop-in.
Product Videos
Custom Field
YEAR 1989-1998
MAKE DODGE
ENGINE 5.9L
