Description

The model number for the ZF transmission (7003) is S5-47. This model number can be divided into three parts. First, "S" designates a synchronized transmission. Second, "5" designates the number of forward gears. Finally, "47" is the approximate maximum input torque capacity in tens of lb-ft. In this case 47 equals 470 lb-ft input torque capacity.

The S5-47 ZF transmission is available in both wide ratio and close ratio versions. The wide ratio version is available for all F-Series vehicles over 8500 lbs. GVW, all engines (6007), except F-Super Duty equipped with a diesel engine. The close ratio version is available only in F-Series vehicles with a 7.3L diesel engine and a GVW over 8500 lbs. The ratios are as follows:

	1st	2nd	3rd	4th	5th	Reverse
Close Ratio (Diesel)	5.08	2.60	1.53	1.0	0.77	4.66
Wide Ratio (Gasoline Diesel)	5.72	2.94	1.61	1.0	0.76	5.24

The transmission features an aluminum case (7005) with an integral clutch housing. Because of the aluminum case, the tapered roller bearings of the transmission shafts must be fitted under preload. This is because heat expansion of the aluminum case is greater than that of the steel alloy mainshaft and countershaft cluster gear (7113). If the bearings were not pre-loaded, this would result in excessive end play when the case expands in warm, loaded operating conditions. The transmission also features shrink-fit gears on the countershaft cluster gear. Shrink-fit gears are connected to the countershaft cluster gear by friction only, rather than connected through splines. The gear is heated and lightly pressed onto the countershaft cluster gear. The subsequent cooling of the gear provides the shrink fitting. The countershaft cluster gear is serviced as an assembly.

NOTE: For vehicles equipped with the 7.3L diesel engine, this transmission requires use of synthetic MERCON® Multi-Purpose Automatic Transmission Fluid E6AZ-19582-B or MERCON® equivalent meeting Ford specification ESR-M2C163A2.