Complete disassembly, inspection, rebuild, and reinstallation of the U880E/U881E 8-speed automatic transmission, including replacement of worn clutches, seals, and bearings.

Warnings

Tools required

Parts

• Transmission overhaul kit (U880E/U881E specific) × 1 — Use OEM specification
• Torque converter (if replacement needed) × 1 — Use OEM specification
• Transmission filter × 1 — 35330-0W040
• Transmission pan gasket × 1 — 35168-0W010
• Drain plug washer × 1 — 90341-18003
• Front pump seal × 1 — Use OEM specification
• Output shaft seal × 1 — Use OEM specification
• Input shaft seal × 1 — Use OEM specification
• Valve body gasket set × 1 — Use OEM specification
• Case bolts (if reuse not recommended) × 1 — Use OEM specification
• RTR silicone sealant (Toyota FIPG) × 1 — 08826-00080

Fluids

• Toyota WS ATF — 10 qt

Preparation

1. Verify transmission failure mode and confirm rebuild is necessary versus replacement
2. Obtain complete rebuild manual with clearance specifications for U880E/U881E transmission
3. Park vehicle on level surface and set parking brake
4. Disconnect negative battery terminal and wait 90 seconds for airbag system to discharge
5. Raise vehicle on lift or support securely on jack stands at manufacturer lift points
6. Remove engine under covers and splash shields
7. Drain transmission fluid from drain plug and remove pan to access additional fluid
8. Mark driveshaft and companion flange orientation if AWD (this is FWD, skip)
9. Clean exterior of transmission thoroughly before removal to prevent contamination
10. Prepare clean workspace with transmission stand for rebuild process

Procedure

1. 1

   Remove transmission from vehicle
   Disconnect battery cables completely. Remove air intake assembly and battery tray for access. Disconnect transmission cooler lines at radiator (cap open lines immediately). Disconnect shift cable, electrical connectors (output speed sensor, input speed sensor, solenoid harness, range sensor). Remove starter motor. Install engine support fixture across engine bay to support engine weight. Remove front wheels and disconnect lower control arms from steering knuckles. Remove both front axle shafts from transmission (support axles to prevent damage to CV boots). Drain remaining fluid. Support transmission with transmission jack. Remove transmission mounting bolts and crossmember. Carefully lower transmission while guiding torque converter (keep converter tilted upward to prevent dropping). Once clear, tilt transmission and remove from vehicle.
   Torque spec

   Mounting Bolts61 Nm (45 lb-ft)
2. 2

   Remove external components and torque converter
   Mount transmission securely on transmission stand. Remove torque converter by pulling straight out (may require gentle prying). Inspect torque converter for debris, cracks, or worn friction surface. If reusing, set aside in clean area. Remove transmission pan bolts in criss-cross pattern and remove pan. Remove transmission filter and valve body cover. Disconnect valve body electrical connections and remove valve body assembly (10-12 bolts). Keep valve body components organized and protected from contamination.
   Torque spec

   Pan Bolts16 Nm (12 lb-ft)

   Cover Screws11 Nm (8 lb-ft)
3. 3

   Disassemble transmission case halves
   Remove all case bolts noting different lengths and positions. Carefully separate case halves using plastic mallet and light prying at designated pry points (consult service manual). Do NOT pry between sealing surfaces. Once separated, inspect case halves for cracks, porosity, or damage. Remove oil pump assembly from front case by removing retaining bolts. Extract clutch packs, planetary gear sets, and shafts in order, documenting position and orientation of each component with photos.
4. 4

   Inspect and measure all internal components
   Clean all parts in solvent and dry with compressed air. Inspect all clutch plates for glazing, burning, or delamination. Measure clutch plate thickness with micrometer and compare to specifications (typically 1.6-2.0mm for friction plates). Check clearances on all clutch packs using feeler gauges. Inspect all bearings for pitting, roughness, or wear. Check all snap rings for deformation. Inspect planetary gear sets for chipped teeth or wear. Measure shaft end play with dial indicator. Check all bushings for wear or scoring. Document all measurements and identify parts requiring replacement.
5. 5

   Disassemble and inspect valve body
   Work on clean, lint-free surface. Remove valve body separator plate and gaskets. Carefully remove each valve, spring, and check ball, organizing in order of removal. Inspect all valve bores for scoring or wear. Check all valves for freedom of movement (should slide smoothly under own weight). Verify all springs for correct length and tension per specifications. Clean all passages with compressed air. Inspect solenoids for proper operation and resistance values per service manual (typically 3.5-5.5 ohms for shift solenoids).
6. 6

   Inspect and service oil pump
   Disassemble pump assembly by removing bolts and separating pump body from cover. Remove drive and driven gears. Inspect gears for wear, scoring, or chipped teeth. Measure pump clearances: gear-to-body clearance (typically 0.15-0.20mm), gear end clearance (0.03-0.08mm), and gear tooth tip clearance. Check pump body and cover for scoring or wear in gear contact areas. Verify pump spring free length. Replace pump seal and any worn components. Clean all passages thoroughly.
7. 7

   Replace all seals, gaskets, and wear components
   Remove all old seals from case, shafts, and pump using appropriate seal pullers. Clean all seal bores thoroughly. Install new front pump seal using seal driver. Replace all shaft seals including input shaft seal and output shaft seal. Install new case bushing if wear exceeds specifications. Replace all O-rings and seal rings on clutch drums and shafts. Soak new clutch friction plates in Toyota WS ATF for minimum 30 minutes before installation. Replace all wave plates, snap rings, and thrust washers per overhaul kit.
8. 8

   Reassemble clutch packs
   Install new clutch plates in correct order per service manual (alternating friction and steel plates, starting with specific type per each clutch pack). Install clutch pack return springs and retainers. Use clutch spring compressor to compress pack and install snap rings. After installation, measure clutch pack clearance with feeler gauge for each clutch assembly (C1, C2, C3, C4 clutches - specifications typically 0.8-1.8mm depending on clutch). Adjust clearance using selective snap rings or backing plates as specified. Perform air pressure test on each clutch pack (apply 70-100 psi to feed hole and verify smooth application with no leaks).
9. 9

   Reassemble planetary gear sets and internal components
   Lubricate all bearings, thrust washers, and bushings with Toyota WS ATF. Install planetary gear assemblies in correct order onto output shaft. Install sun gear, planetary carriers, and ring gears per service manual sequence. Verify all thrust washers are properly positioned and retained. Install input shaft assembly. Check end play of all rotating assemblies with dial indicator (specifications typically 0.2-0.6mm). Install one-way clutches in correct orientation and verify proper operation (should freewheel in one direction, lock in other).
10. 10

    Reassemble oil pump and case halves
    Assemble oil pump with new gaskets and seals. Install pump gears with proper orientation. Torque pump cover bolts per service manual specification (not provided in torque list - consult manual). Apply thin bead of Toyota FIPG sealant to case mating surface per service manual pattern. Install all internal components into rear case half. Carefully align and install front case half ensuring all shafts engage properly. Install and hand-tighten all case bolts, then torque in specified sequence per manual (typically 20-35 Nm, consult manual for exact values). Allow sealant to cure per manufacturer specification before proceeding.
11. 11

    Reassemble and test valve body
    Reassemble valve body with new gaskets and separator plate. Install all valves, springs, and check balls in correct positions and orientations. Ensure all valves move freely. Install solenoid assembly with new O-rings. Torque valve body bolts to specification in criss-cross pattern. Install new valve body-to-case gasket. Position valve body onto case and install bolts finger-tight. Torque valve body mounting bolts to specification in sequence. Connect electrical harness to solenoids.
    Torque spec

    Cover Screws11 Nm (8 lb-ft)
12. 12

    Install filter, pan, and torque converter
    Install new transmission filter and O-ring. Install new pan gasket (do not use additional sealant unless specified). Install transmission pan and torque pan bolts in criss-cross pattern to specification. Install new drain plug crush washer and install drain plug to specification. Thoroughly clean torque converter (or install new unit if damaged). Lubricate torque converter hub seal with ATF. Install torque converter onto input shaft, rotating to engage pump drive. Verify converter is fully seated by measuring depth from bellhousing surface to converter mounting pad (should be minimum 13-15mm recessed).
    Torque spec

    Pan Bolts16 Nm (12 lb-ft)

    Drain Plug34 Nm (25 lb-ft)
13. 13

    Reinstall transmission into vehicle
    Clean bellhousing mating surface on engine. Apply small amount of high-temp grease to torque converter pilot. Support transmission on transmission jack and carefully raise into position, ensuring torque converter remains engaged. Align transmission to engine and install all mounting bolts hand-tight. Torque transmission mounting bolts to specification. Install crossmember and torque mounting bolts. Remove transmission jack and engine support fixture. Reinstall both front axle shafts with new circlips. Reconnect lower control arms. Connect all electrical connectors, shift cable, and transmission cooler lines. Install starter motor. Install air intake and battery tray.
    Torque spec

    Mounting Bolts61 Nm (45 lb-ft)
14. 14

    Fill transmission and perform initial checks
    Remove fill plug. Using fluid pump, add approximately 4 quarts of Toyota WS ATF through fill hole. Replace fill plug with new washer and torque to specification. Start engine and allow to idle. With foot on brake, shift through all gear positions, pausing 3 seconds in each position. Return to Park. Check fluid level at operating temperature (160-180°F) with engine running. Add fluid as needed to bring level to correct range (fluid should just drip from fill hole). Install fill plug with new washer and torque to specification. Check for leaks around all connections, pan, and seals.
    Torque spec

    Fill Plug34 Nm (25 lb-ft)
15. 15

    Perform road test and adaptive learning reset
    Using Toyota Techstream diagnostic tool, clear all transmission-related DTCs and perform transmission control initialization procedure. This resets adaptive learning values for new clutch pack clearances. Perform comprehensive road test: verify smooth engagement in all gears, proper shift points at various throttle positions, no slipping or flaring during shifts, and proper operation of lock-up clutch. Monitor transmission temperature during test (should not exceed 230°F during normal operation). After road test, recheck fluid level at operating temperature and top off if necessary. Recheck all connections for leaks. Perform final scan for DTCs and verify no codes present.

Reassembly

1. Ensure all torque specifications are followed precisely, especially case bolts and valve body mounting
2. Double-check that all electrical connectors are fully seated and locked
3. Verify transmission cooler lines are properly secured and not kinked
4. Confirm axle shafts are fully engaged with new circlips installed
5. Install all under covers and splash shields removed during disassembly
6. Reconnect battery and verify no warning lights remain illuminated after initialization

Verification

• Confirm transmission shifts smoothly through all gears with no delay or harshness
• Verify no fluid leaks from pan, cooler lines, seals, or case after test drive
• Check that transmission fluid is at correct level when at operating temperature
• Confirm no diagnostic trouble codes are present using scan tool
• Verify shift points occur at correct vehicle speeds per transmission specification
• Test lock-up clutch engagement on highway (should engage smoothly at approximately 45-50 mph in higher gears)
• Monitor transmission temperature gauge to ensure normal operating temperature range
• Verify Park pawl properly engages and holds vehicle on incline

More procedures for this vehicle