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Cummins · Models: 4B / ISB / QSB
181866 Cummins THERMOSTAT KIT
Commercial diesel cooling system. Match the listed part and engine identifiers before ordering.
2-Year WarrantyPAI Industries
$20.97$22.97
Save $2.00
In stock — ships same day
117 available
PAI Part #181866
JAK'S Part #JAKS-181866
Complete The Rebuild
Suggested Additional Parts
Commonly sold with this product. These parts are sold separately.
| Brand | PAI Industries |
| Part Category | Cooling System |
| Sub-Type | Thermostat |
| Engine Make | Cummins |
| Engine Model | 4B · ISB · QSB |
THERMOSTAT KIT
Fits:
- CUMMINS 4B ENGINES 3.9
- CUMMINS ISB ENGINES
- CUMMINS QSB SERIES ENGINE
- CUMMINS ISF 3.8 ENGINE
OEM cross-references:
- CUMMINS 3954830
- CUMMINS 3974371
- CUMMINS 4929644
- CUMMINS 5292711
- CUMMINS 5292712
- CUMMINS 5292744
- CUMMINS 5627589
Warranty: 24 months
Discovery models are listed below. Confirm the complete application and any ESN/CPL or size restrictions before ordering.
Cummins 4B ISB QSB
Most PAI parts carry a 2-year unlimited-mileage PAI warranty — 3 years on the High Performance tier, 1 year on Excel by PAI. See Warranty & Returns for full coverage terms, or call a specialist to confirm the exact coverage on this part.
PAI published warranty tiers: High Performance — 3-Year · Genuine PAI — 2-Year · Excel — 1-Year, unlimited mileage. The badge beside the price shows this product's recorded term; when no badge is shown, confirm coverage with a specialist.