General Servicing: Ignition: Distributor: Notes
5.0L 4-Bbl. Federal engines use Electronic Spark Timing (EST) system with detonation sensor and 5-pin module. All other models use a standard HEI system with 4-pin module.
NOTE:
High energy ignition system module must be replaced as a unit. A liberal coat of silicone grease MUST be applied to both the module and the surface on which it will be mounted.