A telescoping cyl is a single acting type, remember most telescoping cyl's are in a vertical application where the weight brings it back down, Forklifts, Man lifts, Dump Trucks. Also on a telescoping cyl. the farther it extends the faster it travels. Remember that a telescoping cyl. is a series of progressively smaller tubes, as the tube extends the area the oil goes get's smaller in diameter with each stage requiring less oil to travel the same distance, problem is the pump don't know that and just keeps on putting out the same amount of oil and the cyl. just progressively moves faster.
