Code Details
| Display code | SPN 175 FMI 0 |
|---|---|
| SPN | 175 |
| FMI | 0 |
| OEM code | None listed |
| Manufacturer | Mack |
| System | Engine �?lubrication / cooling |
| Component | Engine oil cooler / cooling system / oil temperature sensor |
| Source address | Unknown or not applicable |
| Severity | high |
| Review status | source backed |
| Source confidence | medium |
| Last reviewed | 2026-06-12 |
Plain-English Meaning
The Mack MP8 oil cooler is shared with the Volvo D13 �?both use an internal oil cooler that relies on coolant flow to remove heat from the engine oil. SPN 175 FMI 0 means the oil temperature sensor detected temperatures above the normal range. On Mack Anthem, Pinnacle, and Granite trucks, cooling system issues are the most common cause. Scale buildup in a deferred coolant maintenance situation is a known cause of oil cooler performance decline on the MP8. On Mack Anthem and Pinnacle trucks with the MP8, engine oil temperature rises when the EGR cooler is bypassing heat into the oil system at high rates or when the oil cooler capacity is reduced by restricted flow. VCADS Pro monitors oil temperature in real time alongside EGR cooler outlet temperature. If the EGR cooler temperature differential is abnormally low, EGR cooler bypass — from a cracked EGR cooler — is indicated. Oil cooler restriction shows as steadily rising oil temperature under load without a corresponding EGR anomaly.
SPN 175 FMI 0 is Engine Oil Temperature above normal. VCADS Pro (PTT) displays live oil and coolant temperatures on the Mack MP8. The differential between these two readings at steady load is the key diagnostic data point for identifying whether the issue is external (cooling system) or internal (oil cooler).
Common Symptoms
- Oil temperature warning on the Mack instrument panel
- Engine derate to protect against oil temperature damage
- May occur with elevated coolant temperature on grades or in hot conditions
Possible Causes
Possible causes may include the items below. The list is not a parts diagnosis.
- Cooling system deficiency: low coolant, restricted radiator, or fan clutch issue
- Oil cooler fouled with scale from deferred coolant maintenance
- Stuck thermostat
- Extreme operating conditions exceeding cooling capacity
First Checks
- Connect VCADS Pro and monitor oil temperature versus coolant temperature under load
- Inspect coolant level, condition, and inhibitor levels
- Test fan clutch engagement
- Inspect radiator for external blockage
- Monitor oil temperature and EGR cooler temperatures together in VCADS Pro under load
- Check for EGR cooler leaks by inspecting the coolant reservoir for signs of oil contamination
Can I Keep Driving?
The Mack MP8 will derate to protect the engine. Address immediately.
Related Codes
Related Lookup Pages
Sources
- Mack Trucks Service Support Public Resources Mack Trucks Inc. · oem · accessed 2026-06-11 · confidence medium
Source: Mack Trucks Inc., Mack Trucks Service Support Public Resources. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - Volvo Trucks / Mack Trucks Technical Support Volvo Trucks North America / Mack Trucks Inc. · oem · accessed 2026-06-10 · confidence medium
Source: Volvo Trucks North America / Mack Trucks Inc., Volvo Trucks / Mack Trucks Technical Support. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - SAE J1939 Standards Collection SAE International · official · accessed 2026-05-05 · confidence medium
Source: SAE International, SAE J1939 Standards Collection. This page paraphrases factual fields only and is not a substitute for the original document.
Open source
FAQ
Is the Mack MP8 oil cooler the same part as the Volvo D13 oil cooler?
In many configurations, the MP8 and D13 share the same oil cooler assembly. Confirm with VCADS Pro (PTT) parts look-up or the Mack/Volvo parts portal for the specific engine serial number and model year.
What is the difference between PTT and VCADS Pro for diagnosing the Mack MP8?
PTT (Premium Tech Tool) is the Mack-branded version of the same software platform as VCADS Pro for Volvo. The underlying diagnostic capability for the shared Mack/Volvo engine platform is equivalent. PTT is accessed through the Mack dealer network; VCADS Pro through Volvo dealers. Both can diagnose the EMS3 engine management system used in the MP8.
Can the Mack MP8 fan clutch be tested without VCADS Pro?
The fan clutch can be inspected manually for engagement at high temperature by checking whether the fan blade can be rotated by hand with the engine hot and shut off (a freely spinning fan when it should be locked suggests a failed clutch). However, VCADS Pro allows a commanded activation test that confirms the clutch responds to an electronic request �?which is necessary to confirm the control circuit, not just the mechanical condition.