My friend is on the road with a recently purchased 1985 Itasca Sunflyer. It has a GMC P30 chassis (light-duty truck, 23’ model RV). They were driving down the highway when suddenly the gas pedal was gone. There was no sound as it happened. The gas pedal just suddenly revved the engine instead of powering the rv. It could still go in low gear, at about 15 mph, but all the high gears were gone. They drove to a place to park, but the engine was overheating after a short distance.
Does that sound like the transmission needs to be replaced? How much would that cost? Or could it be something repairable, and how much would that cost? They’re in a small town with no garages open on the weekend so no diagnosis until Monday at the earliest. Any sound advice appreciated–thanks.