Hi Tim, I've been using Trolley jack oil (Iso32) for the last year. One thing though, my rams were leaking prior to filling with this stuff, so I thought, Eh! Nothing to loose! Using Lucas Stop leak aswell. Still leaking but not as much. Last top up 6 months ago. No problems with the operation so far. And the hood has been up and down a few times this summer. But to be honest, if there was no leak I would have probably gone genuine.