have a 2001 f150 2wd xlt,last monday out of the blue steering box blew sector shaft seal at pitman arm,ordered edelman Part #8772 installed without dust cap,no leaks until i turned steering hard to left or right at end.shaft is not pitted or worn.can someone tell me why it blew or not sealing,is this the the right part #.just ordered duralast #8520 from autozone hoping this one will work.Hard time to put c clip in place and was not seated properly first time so removed dust seal and put c clip against
washer spacer.can someone help me out.