P00B7 on RAM: How to Diagnose & Fix
Engine Coolant Flow Low/Performance
1 RAM model · 1 documented issue · 1 critical · $250-$700 repair
P00B7 on RAM by model: symptoms, diagnosis and fix
The concentric (belt-driven) water pump on 6.7L Cummins trucks can leak coolant and suffer bearing failure. NHTSA recall 17V562000 covered 2013-2017 Ram 2500/3500 and cab-chassis trucks whose water pump lacked a vent hole, allowing coolant to leak onto hot engine components and create a fire risk. Separately, owners report the pump bearing seizing and throwing the serpentine belt, one at just 32,000 miles while towing, leaving the truck without cooling or charging. Symptoms include coolant weeping from the weep hole, whining/grinding from the pump, and overheating.
Common Symptoms
- Coolant leak / weeping from water pump weep hole
- Whining or grinding from the front of the engine
- Overheating
- Thrown or shredded serpentine belt
- Low coolant warning
- Sweet coolant smell
How to Fix
Check the VIN against recall 17V562000 (repair is free at a Ram dealer for affected trucks). For out-of-warranty failures, replace with the updated vented water pump (Cummins service PN 5473057 supersedes earlier numbers) and inspect the serpentine belt, tensioner, and fan hub while access is open. Address any coolant weeping promptly to avoid belt loss and overheating.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mopar 68414058AB updated 6.7L water pump with seal
2013-2018 Ram 2500 6.7L VIN L as explicitly listed; supersedes 68414058AA and includes seals. Check T51 VIN eligibility before buying.
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Sources for this issue (3)
P00B7 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P00B7 mean on a RAM?
P00B7 stands for "Engine Coolant Flow Low/Performance." P00B7 means the powertrain control module has determined that coolant flow through the engine's cooling system is too low or not performing as expected. The computer compares signals — typically from the engine coolant temperature sensor and a second temperature sensor (such as the radiator outlet) — and flags this code when the readings indicate coolant isn't circulating properly to manage engine temperature. Restricted flow can let the engine run hotter than designed, risking overheating. The cause is usually a thermostat, water pump, low coolant, or a sensor reading problem. On RAM it is documented across 1 model: 2500.
What are the most common causes of P00B7?
The most common causes of P00B7 are: Stuck or faulty thermostat, Low coolant level or air pockets in the system, Failing water pump (mechanical or electric), Faulty engine coolant temperature or radiator temperature sensor, Clogged radiator, hoses, or coolant passages with sediment/debris, Coolant leak reducing system volume, Wiring/connector faults at the temperature sensors or PCM control issue. The specific cause varies by vehicle.
How much does it cost to fix P00B7 on a RAM?
Published repair estimates on RAM range from $250 to $700 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P00B7 on a different make?
View P00B7 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.