That is the likely problem. Sometimes though the rubber hoses close up on the inside either causing a pressure drop to one side or causing one side not to release pressure, causing it to drag.
I would check the rubber hoses. They probably cost almost as much to replace though.
my .02

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1959 Gravely LI, 1963 Gravely L8, 1973 Gravely C12
1982 380SL
1978 450 SEL 6.9 euro restoration at 63% and climbing
1987 300 D
2005 CDI European Delivery
2006 CDI Handed down to daughter
2007 GL CDI. Wifes