Description
PAI 181887 is a 180 °F (82 °C) non-vented engine coolant thermostat for the Cummins heavy-duty range (N14 / ISX / ISM / M11 / L10) and the mid-bore ISB / QSB / B family in dual-thermostat configurations. The 3.19″ OD body with 2.27″ ID seat replaces Cummins 4336659, 4973373, 4952204, 4318197, 3335550, and 2882757. Backed by PAI’s 2-year unlimited mileage warranty.
Signs You Need a New Thermostat
- Engine overheating or running hotter than normal
- Engine running cold and not reaching operating temperature
- Temperature gauge cycling rapidly or fluctuating
- Cooling-fan cycling more frequently than normal
- Coolant temperature codes / check-engine lamp
- Coolant leak at the thermostat housing
Specifications
| Manufacturer | PAI Industries |
|---|---|
| Part Number | 181887 |
| Part Type | Engine coolant thermostat |
| Opening Temperature | 180 °F (82 °C) |
| Outside Diameter | 3.19 in |
| Inside Diameter | 2.27 in |
| Vented | No |
| Configuration | For dual-thermostat systems |
| Gasket Included | No (order separately) |
| Warranty | 2-year unlimited mileage |
Cross References
This part replaces or is equivalent to the following part numbers:
- Cummins: 4336659, 4973373, 4952204, 4318197, 3335550, 3335549, 2882757
- Interstate McBee: M-4336659, M-4973373, M-4952204, M-3335550
- PAI: 181887, 181831, 181831-001
Applications
This 180 °F thermostat fits the following Cummins engine families (dual-thermostat configurations):
- Cummins N14 Celect / Celect Plus (1991–2000)
- Cummins ISX, ISX15, ISX12 (dual-stat configurations)
- Cummins ISM, M11, M11 Celect, QSM11 (1993–2010)
- Cummins L10, L10E, L10G
- Cummins ISB 5.9L, ISB 6.7L, QSB 4.5L, QSB 6.7L
- Cummins B5.9 / B6.7 industrial
Representative trucks and equipment using these engines:
- Freightliner Cascadia, Columbia, Century, Coronado, FLD, Classic
- Kenworth T680, T880, T800, W900, T660, T600
- Peterbilt 579, 389, 388, 387, 386, 379, 378
- International ProStar, LoneStar, 9200, 9400, 9900
- Volvo VN, VNL, VNM (Cummins-powered variants)
- Western Star 4900, 5700
This thermostat is for dual-thermostat configurations. For single-thermostat ISX15/ISX12/ISM applications see PAI 181930 (Cummins 4318947). Verify ESN and thermostat configuration per Cummins TSB130055 before ordering. Replace housing gasket on installation.
