[Marshall V. Daut]

Should a broken rear axle or sheared hub key not be at fault, remove the clutch inspection cover from the top of the bellhousing and examine the clutch disk with a flashlight. If it came apart (springs and/or lining separation), you will still feel resistance as you push in the clutch pedal, but the power won't be transmitted from the engine to the transmission. This will result in the symptoms you are experiencing. The gears won't grind when you try to shift because the transmission's input shaft is not turning with the clutch pressure plate, disk and flywheel. So, you could be fooled into thinking all is o.k. inside the bellhousing. A blown clutch disk happened to me on a cross-country trip in 1974, catching me without a spare disk. It took two days in a Missouri small town to come up with a new one so that I could continue back to Arizona. Since that day, I always carry a spare disk under the seat.
Marshall