Just aquirred a vehicle with a 350/350 combo. Took it on it's first road trip Sunday and quickly noticed it only shifted once from low to 2nd. Not familiar with a TH350 but Wikipedia says it's a 3-speed tranny. Any idea why it's not shifting into high gear? Runs great but feels comfortable at 50-55 mph and got 19 mpg. Verified shifting by the tach. RPM's dropped only once when it went from 1st to 2nd. Not again.
Any help appreciated!