RRPYAC8.75-28.0 Mopar A-Body Axle replacement Big Bolt Pattern. (Pair) A long standing problem with A-Body Mopars has been the lack of support in the way of brakes and wheels using the small 4" bolt pattern seen on early A-Body Mopars. This pair of axles converts Dart, Duster, Demon, Barracuda, Valiant, Signet, etc. from 5 on 4" bolt pattern to larger 5 on 4-1/2" pattern. The bearings below also allow the use of rear Wilwood disc brakes with or without a parking brake and can be used on any 8-3/4 Dodge, Plymouth, or Chrysler axle to allow the use of Wilwood brakes or simply replace the stock adjustable bearing.