No surprises here.I've worked with lots of seals and this is not uncommon.Loctite around the seal is good[read Jimmy's rsponse on the "other" board].What I have done on brake rotor seals is to gently ding a series of small tits around the top,outside corner with a flat blade chisel.Then I just tap in place.The corner I'm talking about is the one that you see on the od of the seal at the end of the axle tube when the seal is in place[the parting line].This creates a bit of an interference fit to retain the seal without damaging the housing of the diff.Add some Loctite when you install the seal,and you should be good to go.Hope that helps a bit.Post back and let me know how it goes or if you have any more questions.
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Give em' hell!
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Give em' hell!