Transmission Disassembly

On all models, remove speedometer driven gear assembly and front cover with oil seal. See Fig 1. Using snap ring pliers, remove countergear front bearing snap ring and mainshaft front bearing snap ring. On 4WD models, remove transfer flange using Transfer Flange Holder (J37221) with socket wrench and transfer rear case assembly. On 2WD models, remove extension housing and intermediate plate with gear assembly.
On 4WD models, remove detent plugs, springs and balls. See Fig 2. Remove transfer switch, bridge and 2nd-4th shift rod-to-shift arm spring. Engage 2nd-4th sleeve with front output gear. Drive spring pin from 2nd-4th block. Remove 2nd-4th shift rod, 2nd-4th shift arm and 2nd-4th block.
Remove interlock pin and interlock pin spring. See Fig 2. Drive out high-low shift arm spring pin and remove high-low shift rod, high-low shift arm and high-low block.
Remove mainshaft end bearing snap ring. See Fig 2. Using Bearing Remover (J37217) with Bearing Plate (J8433), remove mainshaft end ball bearing. Engage 3rd-4th synchronizer with 3rd gear and 1st-2nd synchronizer with low gear. Remove mainshaft end lock nut using Lock Nut Wrench (J37219). Remove washer.
On 4WD models, remove high-low synchronizer assembly, high-low block ring and transfer input gear using Universal Puller (J22888). See Fig 2. Remove needle bearing, bearing collar and ball. Using snap ring pliers, expand front output shaft bearing snap ring and tap out front output gear assembly with a plastic hammer. Using snap ring pliers, expand transfer countergear bearing snap ring and remove transfer countergear assembly Remove transfer case and intermediate plate with gear assemblies.
On all models, remove detent spring plate, detent springs and detent balls from intermediate plate. See Fig 3. Remove spring, 5th-reverse shift rod, 5th-reverse shift arm, reverse inhibitor and reverse inhibitor spring. Drive out spring pins and remove 1st-2nd shift rod, 3rd-4th shift rod, 3rd-4th shift arm, 1st-2nd shift arm and interlock pins.
On 4WD models, remove oil seal collar, ball bearing and retainer using Bearing Remover (J37217) and Bearing Plate (J8433). See Fig 4. On 2WD models, remove bearing snap ring and ball bearing using bearing remover with bearing plate, snap ring, clip, speedometer drive gear, retainer snap ring and retainer.
On all models, remove thrust plate, thrust washer and lock ball. Remove reverse gear shaft snap ring and countergear bearing snap ring. Engage 5th-reverse synchronizer with 5th gear. Using universal puller, remove countergear ball bearing and counter 5th gear while also removing reverse shaft, reverse idler thrust washer gear, and reverse shaft pin.
Remove counter reverse gear, 5th gear, 5th block ring and needle bearing. Engage 3rd-4th synchronizer with 3rd gear and 1st-2nd synchronizer with 1st gear. Attach Holding Fixture (J37224) and Holding Base (J3289-20) to mainshaft front bearing and countergear front bearing. Remove mainshaft nut using Mainshaft Nut Wrench (J37219).
Remove 5th-reverse synchronizer assembly, reverse block ring and reverse gear together. Remove bearing plate and screws using Torx Bit Wrench No. 45 (J37225). Using snap ring pliers, hold open mainshaft bearing snap ring and remove mainshaft assembly. Using snap ring pliers, hold open countergear bearing snap ring and remove countergear assembly.

Fig 1: Exploded Views Of Transmission Major Components

Courtesy of ISUZU MOTOR CO.

Fig 2: Exploded View Of Transfer Case Assembly (4WD)

Courtesy of ISUZU MOTOR CO.

Fig 3: Exploded View Of Shift Rod & Arm Assemblies

Courtesy of ISUZU MOTOR CO.

Fig 4: Exploded View Of Reverse & 5th Gear Assemblies

Courtesy of ISUZU MOTOR CO.