Transaxle Reassembly

NOTE: All selective snap ring and thrust washer measurements taken during disassembly must be rechecked at appropriate reassembly stage.

Install manual shaft, detent lever assembly and parking pawl, if removed. Install drive sprocket support, transaxle input speed sensor and wiring harness. See Figure . Install torque converter seal.
Install lo/reverse band and ensure anchor engages band. Install fretting ring with open end at bottom. Install oil cooler return fitting "O" ring to coast and forward clutch assembly. Using Forward/Coast Clutch Puller (J-39053), install coast and forward clutch assembly into case. See Figure . Make sure anchor holes in support align with holes in case.
Install final drive internal gear with groove up. Install snap ring with open end in scavenge tube area. Rotate support counterclockwise against spline. See Fig 1 .
Install reaction shell and 3rd clutch housing. Install the input shaft selective washer and thrust bearing on the 3rd clutch housing. See Figure . Install the 4th band and reverse clutch assembly. Refer to Fig 2 . Make sure band pin seat engages servo pin. Install reverse clutch housing and thrust washer.

Fig 1: Loading Support Counterclockwise
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Fig 2: Reaction Shell, 4th Band, 3rd Clutch & Reverse Clutch Housing
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Fig 3: Valve Bodies, Oil Pump, Sprockets & Drive Chain Assemblies
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Install seal on drive sprocket support. Using Sizer (J-39064-2), size seal. Install backing plate, 2nd clutch plates, apply plate and waved plate.
Place scavenge tube seal on driven sprocket support and install driven sprocket support. Install drive chain (in the same direction as removed) to drive sprocket support. Tap sprockets until seated. Place thrust roller bearings on sprockets.
To air check reverse, 2nd and 3rd clutches at drive sprocket support, go to next step. Install island gasket and case cover gasket. Install case cover allowing wiring harness connector to pass through opening in case cover. Install bolts in correct position and hand tighten only. See Fig 4 .
Using 40 psi (2.7 kg/cm² ) of air pressure, air check clutches and servos. Reverse, 2nd and 3rd clutches may be checked at driven sprocket support. Coast and forward clutches may be checked through passage in lower case. See Fig 5 . To check Reverse clutch, 3rd clutch or 4th servo, fabricate an air checking plate. See Fig 6 .
Trace template as shown. See Fig 6 . Using 3/8-1/2" thick aluminum or plastic, cut out an air checking plate to match template. Mark and drill holes in plate. Bolt plate to case. Air check clutches and 4th servo.
NOTE: About 90-100 psi (6.2-6.9 kg/cm² ) of air pressure are required to apply the 3rd clutch.

Fig 4: Installing Case Cover
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Fig 5: Air Checking Clutches
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Fig 6: View Of Air Checking Template & Air Checking Transaxle
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Fig 7: Case Cover, Oil Pump & Upper Valve Body Mounting Bolts
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Check input shaft end play. See Figure . Install Input Shaft End Play Fixture (J-39686) to front side of transaxle. Make sure "J" tab on fixture rests on input shaft. Mount Dial Indicator Post 5 (J-25025-7A) and Dial Gauge (J-8001-3) to check end play. Push down on handle. End play should be .004-.034" (.10-.85 mm). Input shaft thrust washers size range is .089-.195" (2.27-4.97 mm) in increments of .012" (.30 mm).
Tighten case cover bolts and studs in a criss-cross pattern. Install 2 check balls. See Fig 4 . Install upper valve body. See Fig 7 . Tighten bolts starting with center ones and working to outside ones. Install side filter.
Install TCC/VCC solenoid and transaxle pressure control solenoid. Install oil pump assembly. Tighten bolts starting with center ones and working to outside ones. Install oil pan and tighten bolts in a star pattern. Install 4th servo. See Fig 3 . Make sure tab on servo piston aligns with slot in case (some models).
Using a long thin piece of .025" (.60 mm) shim stock, slide lo/reverse band into position. Install lower valve body and channel plate. See Fig 8 . Install bolts and tighten by hand. Remove shim stock.
Install oil transfer plate and hand tighten bolts. See Fig 8 . Connect wiring harness and manual valve. Tighten channel plate and oil transfer plate bolts in a criss-cross pattern. Install scavenge screens. See Fig 3 . Install pan gasket and tighten bolts in a star pattern.
Assemble and install final carrier, output shaft and differential carrier. See Fig 3 . Engage parking pawl to hold final drive unit. Tighten differential carrier bolts.
Install scavenge tube and seal. Install selective thrust washer and roller thrust bearing onto output shaft. See Fig 3 . Install extension housing and hand tighten bolts.
Mount Dial Indicator Post (J-39687) and Dial Gauge (J-8001-3) to check end play. Pry up on speed sensor rotor through speed sensor hole. End play should be .006-.025" (.15-.65 mm). See Figure .
If necessary, adjust end play with selective final drive-to-case thrust washer. See FINAL DRIVE-TO-CASE SELECTIVE THRUST WASHER SIZES . Tighten extension housing bolts. Install oil cooler return fitting to forward and coast clutch support. Install axle seals, oil pump drive shaft, torque converter and vehicle speed sensor.

FINAL DRIVE-TO-CASE SELECTIVE THRUST WASHER SIZES

Washer ID Color	Thickness: In. (mm)
Orange	.137-.141 (3.49-3.59)
White	.131-.136 (3.35-3.46)
Blue	.126-.130 (3.21-3.32)
Pink	.120-.125 (3.07-3.18)
Brown	.115-.119 (2.93-3.04)
Green	.110-.114 (2.79-2.90)
Black	.104-.109 (2.65-2.77)

Fig 8: Locating Lower Valve Body & Oil Pan Mounting Bolts

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Fig 9: Hydra-Matic 4T80-E Thrust Washers & Bearing Locations

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Fig 10: Identifying Hydra-Matic 4T80-E Lip Seal Locations

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4T80-E GEAR RATIOS

Gear Range	Ratio
First	2.96
Second	1.63
Third	1.00
Fourth	.68
Reverse	2.13