| 4 Synchro Internal Gearbox | 
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			| 1968 On | 
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			| Fortunately for the majority of our customers, 4 synchro gearboxes are much easier to identify and classify than their 3 synchro predecessors (parts  | 
		
		
			| availability is considerably better, too, but not brilliant sometimes).  The two main change points are 1979, when the gear shafts and several of the  | 
		
		
			| bearings were modified, and 1982 - approximately - when A Plus gears were introduced. | 
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			| A Plus gears were introduced on the Mini round about 1982 (at different times on different models...), and have a sharper tooth angle and different pitch  | 
		
		
			| making them quieter than, but definitely not interchangeable with, the earlier gears.  Looking in the gearbox, A Plus gears can be identified by the  | 
		
		
			| presence of a circumferential groove in the centre of the teeth, and the final drive pinion on the gearbox mainshaft is machined flush on both sides.     | 
		
		
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			| The following summaries should help with the identification of your gearbox and give you points to watch out for when ordering parts: | 
		
		
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			| 1968-73 Saloon and Estate, 1968-75 Van and Pick Up | 
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			| Pre-A Plus gears.  Direct/remote gearchange type reverse gear and mainshaft bearing retainer (four screw fitting).  9/16" dia. nose on 3rd motion shaft,  | 
		
		
			| two step layshaft, laygear takes two large bearings and one small bearing.  Different ratios for 1275 models. | 
		
		
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			| 1973-79 Saloon and Estate, 1975-79 Van and Pick Up | 
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			| Pre-A Plus gears.  Rod gearchange type reverse gear and mainshaft bearing retainer (4 screw fitting).  9/16" dia. nose on 3rd motion shaft, two step  | 
		
		
			| layshaft, laygear takes two large bearings and one small bearing.  Different ratios for 1275 models. | 
		
		
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			| 1979-82  | 
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			| Pre-A Plus gears (except for final drive pinion on 3.444:1 ratio models, which became A Plus in 1979).  Rod gearchange type reverse gear and mainshaft  | 
		
		
			| bearing retainer (4 screw fitting).  11/16" dia. nose on 3rd motion shaft, three step layshaft, laygear takes one large and one small bearing. Idler and 1st  | 
		
		
			| motion shaft drive gear ratios revised, idler gear bearings in gearbox case revised (diameter change).  Different ratios for 1275 models. | 
		
		
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			| 1982 on | 
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			| A Plus gears.  Rod gearchange type reverse gear and mainshaft bearing retainer (4 screw fitting reducing to 3 screw fitting in 1984).  11/16" dia. nose   | 
		
		
			| on 3rd motion shaft, three step layshaft, laygear takes one large and one small bearing.  Different ratios for French 1275 models in the 1990s. | 
		
		
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			| Close ratio and straight cut close ratio gear sets are available for 4 synchro pre-A Plus and A Plus gearboxes, as a special order.  Please contact | 
		
		
			| us for details.  Similarly, please contact us if you already have factory-optional helical close ratio or straight cut close ratio gears in your gearbox and | 
		
		
			| you require replacement parts. | 
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			| Reverse Idler Gear | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 1 | 
			22G1034 | 
			REVERSE IDLER, 17/18 teeth, direct/remote gearchange type | 
			1 | 
			1968-73, Saloons and Estates; 1968-75, Vans and Pick Ups. | 
		
		
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			22G1832 | 
			REVERSE IDLER, 17/18 teeth, rod gearchange type | 
			1 | 
			1973-79, Saloons and Estates; 1976-79, Vans and Pick Ups. | 
		
		
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			TUB10020 | 
			REVERSE IDLER, 17/18 teeth, rod gearchange type | 
			1 | 
			1979 on. | 
		
		
			| 2 | 
			TUJ10001 | 
			BUSH, reverse idler | 
			1 | 
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			| 3 | 
			DAM8038 | 
			SHAFT, reverse idler | 
			1 | 
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			| Laygear | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 4 | 
			22G927 | 
			LAYGEAR, 15/20/25/29 teeth, for two step layshaft  | 
			1 | 
			1968-79; not 1275 models. | 
		
		
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			22G1040 | 
			LAYGEAR, 15/20/25/29 teeth, for two step layshaft  | 
			1 | 
			1968-79; 1275 models. | 
		
		
			| 5 | 
			DAM3169 | 
			LAYGEAR, 15/20/25/29 teeth, for three step layshaft  | 
			1 | 
			1979-82; not 1275 models. | 
		
		
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			DAM3168 | 
			LAYGEAR, 15/20/25/29 teeth, for three step layshaft  | 
			1 | 
			1979-80; 1275 models. | 
		
		
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			DAM4931 | 
			LAYGEAR, 15/21/26/30 teeth, A Plus type, for three step layshaft  | 
			1 | 
			1982 on; not 1990-96, 1275 (France).   | 
		
		
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			DAM6238 | 
			LAYGEAR, 15/21/27/31 teeth, A Plus type, for three step layshaft  | 
			1 | 
			1990-96, 1275 (France).   | 
		
		
			| 6 | 
			22G931 | 
			LAYSHAFT, two step type | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
			| 7 | 
			DAM3187 | 
			LAYSHAFT, three step type | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
			| 8 | 
			2A3581 | 
			PLATE, locating reverse idler shaft and layshaft | 
			1 | 
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			| 9 | 
			CHM141 | 
			BEARING, needle roller, laygear, large | 
			2/1 | 
			Qty. 2 fitted to 22G927 and 22G1040 laygears only. | 
		
		
			| 10 | 
			88G396 | 
			BEARING, needle roller, laygear, small | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
			| 11 | 
			13H9513 | 
			BEARING, needle roller, laygear, small | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
			| 12 | 
			22G856 | 
			WASHER, thrust, small, 0.123-0.124" (3.12-3.14mm) | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
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			22G857 | 
			WASHER, thrust, small, 0.125-0.126" (3.17-3.20mm) | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
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			22G858 | 
			WASHER, thrust, small, 0.127-0.128" (3.22-3.25mm) | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
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			22G859 | 
			WASHER, thrust, small, 0.130-0.131" (3.30-3.32mm) | 
			1 | 
			Fit to 22G927 and 22G1040 laygears. | 
		
		
			| 13 | 
			DAM3180 | 
			WASHER, thrust, small, 0.121-0.123" (3.07-3.12mm) | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
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			DAM3181 | 
			WASHER, thrust, small, 0.124-0.126" (3.15-3.20mm) | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
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			DAM3182 | 
			WASHER, thrust, small, 0.127-0.129" (3.22-3.27mm) | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
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			DAM3183 | 
			WASHER, thrust, small, 0.130-0.132" (3.30-3.35mm) | 
			1 | 
			Fit to DAM3169, DAM3168, DAM4931 and DAM6238 laygears. | 
		
		
			| 14 | 
			22G860 | 
			WASHER, thrust, large | 
			1 | 
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			| 1st Motion Shaft | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 15 | 
			22G1093 | 
			SHAFT, 1st motion, 17 teeth | 
			1 | 
			1968-79; not 1275 models. | 
		
		
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			22G1371 | 
			SHAFT, 1st motion, 18 teeth | 
			1 | 
			1968-79; 1275 models. | 
		
		
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			DAM3092 | 
			SHAFT, 1st motion, 17 teeth | 
			1 | 
			1979-82; not 1275 models. | 
		
		
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			DAM3167 | 
			SHAFT, 1st motion, 18 teeth | 
			1 | 
			1979-80; 1275 models. | 
		
		
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			DAM4930 | 
			SHAFT, 1st motion, 17 teeth, A Plus type | 
			1 | 
			1982 on; not 1990-96, 1275 (France).   | 
		
		
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			DAM6242 | 
			SHAFT, 1st motion, 16 teeth, A Plus type | 
			1 | 
			1990-96, 1275 (France).   | 
		
		
			| 16 | 
			22G2033 | 
			RING, baulk | 
			1 | 
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			| 17 | 
			CHM172 | 
			BEARING, 1st to 3rd motion shaft, 9/16" int. dia. | 
			1 | 
			Fit to 22G1093 and 22G1371 1st motion shafts. | 
		
		
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			13H9513 | 
			BEARING, 1st to 3rd motion shaft, 11/16" int. dia. | 
			1 | 
			Fit to DAM3092, DAM3167, DAM4930 and DAM6242 1st motion shafts. | 
		
		
			| 18 | 
			ADU7619 | 
			BEARING, 1st motion shaft  | 
			1 | 
			In gearbox case. | 
		
		
			| 19 | 
			22G850 | 
			CIRCLIP, bearing retaining | 
			1 | 
			0.094-0.096" (2.39-2.44mm) | 
		
		
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			22G851 | 
			CIRCLIP, bearing retaining | 
			1 | 
			0.097-0.099" (2.46-2.51mm) | 
		
		
			| For the 1st motion shaft bearing supporting the nose of the shaft in the flywheel housing, please see the 'Flywheel Housing and Clutch Cover' section. | 
		
		
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			| 3rd Motion Shaft | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 20 | 
			22G833 | 
			SHAFT, 3rd motion, 9/16" nose dia. | 
			1 | 
			1968-79. | 
		
		
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			DAM7484 | 
			SHAFT, 3rd motion, 11/16" nose dia. | 
			1 | 
			1979 on. | 
		
		
			| 21 | 
			AAU1365 | 
			BEARING, 3rd motion shaft | 
			1 | 
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			| 22 | 
			ADU4992 | 
			RING, spring, bearing retaining | 
			1 | 
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			| 23 | 
			22A522 | 
			RETAINER, 3rd motion shaft bearing, 4 screw fixing, direct/remote gearchange type | 
			1 | 
			1968-73, Saloons and Estates; 1968-75, Vans and Pick Ups. | 
		
		
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			DAM1756 | 
			RETAINER, 3rd motion shaft bearing, 4 screw fixing, rod gearchange type | 
			1 | 
			1973-84, Saloons and Estates; 1976-84, Vans and Pick Ups. | 
		
		
			| 24 | 
			DAM5996 | 
			RETAINER, 3rd motion shaft bearing, 3 screw fixing, rod gearchange type | 
			1 | 
			1984 on. | 
		
		
			| 25 | 
			SH505071 | 
			SCREW, coarse thread, retainer to gearbox case | 
			4/3 | 
			Qty. 4 fitted to 22A522 and DAM1756 retainers only. | 
		
		
			| 26 | 
			DAM2377 | 
			LOCK TAB, screw | 
			2/1 | 
			Qty. 2 fitted to 22A522 and DAM1756 retainers only. | 
		
		
			| 27 | 
			DAM6047 | 
			LOCK TAB, screw | 
			1 | 
			Fitted to DAM5996 retainer. | 
		
		
			| 28 | 
			2A3714 | 
			SHIM, retainer | 
			A/R | 
			0.003" (0.076mm) | 
		
		
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			2A3715 | 
			SHIM, retainer | 
			A/R | 
			0.010" (0.254mm) | 
		
		
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			| 1st Gear | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 29 | 
			22G1096 | 
			GEAR, 1st speed, 31 teeth | 
			1 | 
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			| 30 | 
			22G2033 | 
			RING, baulk | 
			1 | 
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			| 31 | 
			AAU1815 | 
			BEARING, needle roller, 1st speed gear | 
			1 | 
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			| 32 | 
			22G837 | 
			JOURNAL, 1st speed gear | 
			1 | 
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			| 1st/2nd Synchroniser | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 33 | 
			DAM7455 | 
			GEAR ASS'Y, 1st/2nd synchroniser | 
			1 | 
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			| 34 | 
			BLS107 | 
			BALL, synchroniser | 
			3 | 
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			| 35 | 
			22G2262 | 
			SPRING, synchroniser | 
			3 | 
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			| 2nd Gear | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 36 | 
			22G1094 | 
			GEAR, 2nd speed, 26 teeth | 
			1 | 
			1968-82. | 
		
		
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			DAM4932 | 
			GEAR, 2nd speed, 26 teeth, A Plus type | 
			1 | 
			1982 on; not 1990-96, 1275 (France).  | 
		
		
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			DAM6240 | 
			GEAR, 2nd speed, 25 teeth, A Plus type | 
			1 | 
			1990-96, 1275 (France).  | 
		
		
			| 37 | 
			22G2033 | 
			RING, baulk | 
			1 | 
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			| 38 | 
			AAU1816 | 
			BEARING, needle roller, 2nd speed gear | 
			1 | 
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			| 39 | 
			22G839 | 
			WASHER, thrust, 2nd speed gear | 
			1 | 
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			| 40 | 
			22G843 | 
			PEG, 2nd speed gear  | 
			2 | 
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			| 41 | 
			22G154 | 
			SPRING, 2nd speed gear  | 
			1 | 
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			| 3rd Gear | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 42 | 
			22G1095 | 
			GEAR, 3rd speed, 21 teeth | 
			1 | 
			1968-82. | 
		
		
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			DAM4933 | 
			GEAR, 3rd speed, 21 teeth, A Plus type | 
			1 | 
			1982 on; not 1990-96, 1275 (France).   | 
		
		
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			DAM6241 | 
			GEAR, 3rd speed, 20 teeth, A Plus type | 
			1 | 
			1990-96, 1275 (France).   | 
		
		
			| 43 | 
			22G2033 | 
			RING, baulk | 
			1 | 
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			| 44 | 
			AAU1816 | 
			BEARING, needle roller, 3rd speed gear | 
			1 | 
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			| 45 | 
			22G947 | 
			WASHER, thrust, 3rd speed gear | 
			1 | 
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			| 46 | 
			22G843 | 
			PEG, 3rd speed gear  | 
			1 | 
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			| 47 | 
			22G154 | 
			SPRING, 3rd speed gear  | 
			1 | 
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			| 3rd/4th Synchroniser | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 48 | 
			DAM7456 | 
			GEAR ASS'Y, 3rd/4th synchroniser | 
			1 | 
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			| 49 | 
			BLS107 | 
			BALL, synchroniser | 
			3 | 
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			| 50 | 
			22G2262 | 
			SPRING, synchroniser | 
			3 | 
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			| Final Drive Pinion | 
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			| Ill. No. | 
			Part No. | 
			Description | 
			Qty. Rqd. | 
			Remarks | 
		
		
			| 51 | 
			22G99 | 
			PINION, final drive, 15 teeth | 
			1 | 
			4.333:1 ratio (with 65 tooth 22G443 final drive gear).  | 
		
		
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			22G99 | 
			PINION, final drive, 15 teeth | 
			1 | 
			4.267:1 ratio (with 64 tooth 22G370 final drive gear).  | 
		
		
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			22G99 | 
			PINION, final drive, 15 teeth | 
			1 | 
			4.133:1 ratio (with 62 tooth 22G101 final drive gear).  | 
		
		
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			22G338 | 
			PINION, final drive, 16 teeth | 
			1 | 
			3.938:1 ratio (with 63 tooth 22G340 final drive gear).  | 
		
		
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			22A399 | 
			PINION, final drive, 17 teeth | 
			1 | 
			3.765:1 ratio (with 64 tooth 22A401 final drive gear).  | 
		
		
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			22A399 | 
			PINION, final drive, 17 teeth | 
			1 | 
			3.647:1 ratio (with 62 tooth 22G940 final drive gear).  | 
		
		
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			22A413 | 
			PINION, final drive, 18 teeth | 
			1 | 
			3.444:1 ratio (with 62 tooth 22A411 final drive gear).  | 
		
		
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			DAM3647 | 
			PINION, final drive, 15 teeth, A Plus type | 
			1 | 
			4.333:1 ratio (with 65 tooth DAM3645 final drive gear). | 
		
		
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			DAM3218 | 
			PINION, final drive, 16 teeth, A Plus type | 
			1 | 
			3.938:1 ratio (with 63 tooth DAM3216 final drive gear). | 
		
		
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			DAM4131 | 
			PINION, final drive, 17 teeth, A Plus type | 
			1 | 
			3.765:1 ratio (with 64 tooth DAM4779 final drive gear). | 
		
		
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			DAM4131 | 
			PINION, final drive, 17 teeth, A Plus type | 
			1 | 
			3.647:1 ratio (with 62 tooth DAM4162 final drive gear). | 
		
		
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			DAM2679 | 
			PINION, final drive, 18 teeth, A Plus type | 
			1 | 
			3.444:1 ratio (with 62 tooth DAM2677 final drive gear). | 
		
		
			|   | 
			DAM2808 | 
			PINION, final drive, 19 teeth, A Plus type | 
			1 | 
			3.211:1 ratio (with 61 tooth DAM2806 final drive gear). | 
		
		
			|   | 
			DAM2808 | 
			PINION, final drive, 19 teeth, A Plus type | 
			1 | 
			3.105:1 ratio (with 59 tooth DAM6327 final drive gear). | 
		
		
			|   | 
			DAM5927 | 
			PINION, final drive, 20 teeth, A Plus type | 
			1 | 
			2.950:1 ratio (with 59 tooth DAM5925 final drive gear). | 
		
		
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			TCC10001 | 
			PINION, final drive, 21 teeth, A Plus type | 
			1 | 
			2.762:1 ratio (with 58 tooth TCB10004 final drive gear). | 
		
		
			| 52 | 
			22G48 | 
			NUT, pinion retaining | 
			1 | 
			1968-82. | 
		
		
			|   | 
			DAM7485 | 
			NUT, pinion retaining, A Plus type | 
			1 | 
			1982 on. | 
		
		
			| 53 | 
			DAM6140 | 
			LOCK TAB, pinion nut | 
			1 | 
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