Product Description

Cummins 5292744 — Genuine 190° Engine Coolant Thermostat for 5.9L ISB

MPN: 5292744  |  Also Known As: 190-degree thermostat, coolant thermostat  |  Cross-Ref (ID): Mopar 5086739AB (service number)

Return your third-gen to factory operating temps. The genuine Cummins 5292744 190° thermostat is the OE replacement for 2003–2007 Ram 2500/3500 5.9L ISB. Many OE kits include the sealing ring for a quick, leak-free install.

Features & Benefits

• OE calibration (190°F) for proper warm-up, heater performance, and fan strategy.
• Direct-fit to the factory housing—no modifications required.
• Durable wax element & seat for long, repeatable cycles.
• Helps correct low-temp operation from a stuck-open thermostat.
• Genuine Cummins materials and QC.

Verified Fitment (Automotive)

Notes: Mopar catalogs list service number 5086739AB for 2003–2009 coverage in some databases; real-world diesel retailers position 5292744 as the ’03–’07 5.9L OE 190° thermostat. Always confirm by VIN/ESN for cab-and-chassis or edge cases.

Specifications

• Type: Engine coolant thermostat
• Nominal Temperature: 190 °F
• OE Part Number: 5292744
• Service Cross-Ref: Mopar 5086739AB
• Housing Seal: 3954829 (sold separately if not included)
• Quantity Required: 1 per engine

Often Paired With

• Thermostat housing seal: Cummins 3954829 (recommended every service)
• 180° alternative: Cummins 5292742 (popular for warm climates/towing)
• Vertical water neck: Cummins 3943300 (as needed)
• Fresh coolant: refill/bleed after service

What’s In The Box

• (1) Genuine Cummins 190° Thermostat (5292744)
• Sealing ring may be included in kit—check contents; otherwise order 3954829.

Installation Tips

• Drain coolant below thermostat level; clean housing and block surfaces.
• Lightly lube a new 3954829 seal; orient thermostat correctly.
• Torque housing fasteners to spec; refill and bleed air.
• Verify temperature stabilization on warm-up and road test.

FAQ

WILL THIS FIT MY 2003–2007 5.9L CUMMINS RAM?

Yes—5292744 is the OE 190°F thermostat for 2003–2007 Ram 2500/3500 5.9L ISB.

WHAT SEAL DO I NEED?

Use the Cummins 3954829 thermostat housing seal. Many kits include it, but it’s smart to have one on hand.

HOW DOES THIS DIFFER FROM 5292742?

5292744 is ~190° (stock temp). 5292742 is a 180° alternative often chosen for hot climates or specific tuning goals.

DOES THIS FIT 6.7L TRUCKS?

Some catalogs show overlap via Mopar service numbers, but most 6.7L applications use different part numbers. Confirm by VIN/ESN.

IS THIS A GENUINE CUMMINS PART?

Yes—OE Cummins 5292744.