The tag attached to most differential covers may be used in identifying the axle and/or the gear ratio. However, the tag may have been removed during service and not replaced. Then the axle differential covers may be used for axle identification. The number of bolts securing the differential cover, the size and shape of the differential cover, the gear ratio as given on the ratio tag, and the location and type of fill plug are all useful tools in axle identification. Be sure to note all this information before beginning any maintenance or repairs to the axle.
Fig. The fill plug (1) on the 216 FBI axle-s differential cover (3) is a hex-head, and the identification tag (3) is affixed by two cover bolts
Fig. The fill plug (1) on the 248 FBI axle-s differential cover (4) is a square drive plug, and the ratio tag (3) and model numbers (2) are in separate locations
Fig. The fill plug (3) on the 9 1/4 inch axle-s differential cover (1) is a rubber push-in type, and the ratio tag (2) is fastened by a cover bolt
Fig. The drive axle is originally equipped with a gear ratio identification tag attached by one of the cover bolts