Abstract: A telescopic cylinder comprises a housing, a nestable first sleeve, a nestable second sleeve, and a nestable piston rod. A dividing wall is disposed at at least one of the first ends of the first and the second sleeves thereby defining a first chamber between the housing and the at least one of the first ends of the first and second sleeves, and a second chamber between the at least one of the first ends of the first and second sleeves and the piston rod. A valve extends through the dividing wall for selectively allowing communication from the second chamber to the first chamber when pressure inside the second chamber is above a predetermined pressure. A method of extending a telescopic cylinder where the at least second sleeve extends before the at least first sleeve is also presented.