This is a replacement for an already failed unit. It also failed before installing. Oil leakage outside the shock absorber body when not in use! In fact, open the box and look before sending it to the customer. This oil is well defined and sufficient not to be a by-product for production. So upset. 4 hits and problem not solved with $ still there and looking at another annoying setup because GM engineers have no idea how to put everything together BY HAND and not on a computer screen!