My dad had his waterpump replaced under warranty. He was at like around 80K miles.
Edit,
From the Cummins Website... I thought it was 5yrs/100K, might be a typo but it specifically calls out the waterpump.
Every Dodge Ram 2500/3500 with the Cummins 610 Turbo Diesel engine comes with a 7-year/100,000-mile (160,935 km) warranty for first owners. Your Dodge dealer is fully trained and equipped to handle these engine warranty repairs. To find the nearest location by zip code or city, use the Dodge Dealer Locator.
Second owners are also covered for 7 years/100,000 miles (160,935 km) provided that a transfer fee is paid within 30 days of the purchase.
This coverage includes:
Cylinder block and all internal parts
Cylinder head assemblies
Core plugs
Fuel injection pump and injectors
Gaskets and seals for listed components
Intake and exhaust manifold
Oil pan
Oil pump
Timing gear drive belts and/or chains and cover
Turbocharger housing and internal parts
Valve covers
Water pump and housing
A $100 deductible per repair visit applies after your truck has been in use for 5 years, regardless of mileage. The Cummins Diesel Engine Warranty begins at the end of the Basic Limited Warranty, on the earlier of the following: The date your truck has been in service for more than 36 months; or the date you've put more than 36,000 miles (57,937 km) on the odometer. Towing costs to the nearest Dodge dealer are covered if your vehicle cannot be driven because a covered part has failed.
Vehicles used as a police vehicle, taxi, limousine, postal delivery vehicle, ambulance or rental vehicle are covered for 5 years/100,000 miles (160,935 km), whichever comes first.
See your Dodge dealer for complete warranty details.