I had heard a bunch of guys say they would not drill old axles and have also heard it wasn't worth the cost and I would be better to just upgrade to 40 spline axles (40 spline drilled are lighter than 35 non drilled) so I called moser and and asked if they would drill my 5 year old 35's. They said yes and for only $50 per axle. Needless to say they are going to Moser in the next few weeks.