The contact owns a 2021 GMC Yukon. The contact stated that while his wife was driving at 55 MPH with two child passengers, the vehicle went into LIMP Mode. The driver was able to pull over safely to the side of the road. The contact stated that the check engine warning light was illuminated. The vehicle was taken to the local dealer where it was diagnosed and determined that the crankshaft fractured, causing metal shards to enter the engine. The vehicle was not repaired. The dealer recommended that the engine be replaced. The manufacturer was contacted and referred the contact to the dealer and to the NHTSA Hotline. The failure mileage was approximately 94,558.