If you're looking for a meeting place or a good stop around ½ or halfway between Clifton and Oakdale, PA, you can try Lock Haven, PA, which is about 3 hours west of Clifton, or about 3 hours east of Oakdale, PA.
Other possible places to stop near the midpoint include Fritz, Oval, Forest Hill, Collomsville, and Parvin.
About ¼ or a fourth of the way, you can stop at Hazleton, PA. This is about 1½ hours west of Clifton.
About ⅓ or a third of the way, you can stop at Bloomsburg, PA. This is about 2 hours west of Clifton.
About ⅔ or two thirds of the way, you can stop at Altoona, PA. This is about 4 hours west of Clifton, or about 2 hours east of Oakdale, PA.
About ¾ or three fourths of the way, you can stop at Johnstown, PA. This is about 4½ hours west of Clifton, or about 1½ hours east of Oakdale, PA.
If you drive straight through without stopping at all, the total distance is 373 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 5 hours, 60 minutes.