Newer model, manual transmission equipped Isuzu vehicles, utilize a hydraulic circuit to operate the clutch. The clutch pedal is attached to the clutch master cylinder. Pressing the clutch pedal down pushes a piston inside the master cylinder forward. This forces hydraulic fluid out of the master cylinder along a hydraulic line to the clutch slave cylinder. The fluid moves a small piston inside the slave cylinder which is connected to a pushrod. This pushrod forces the clutch open.
Raise the vehicle and support with jack stand placed underneath the frame.
Remove the cover from the reservoir on top of the clutch master cylinder. It will be located in the engine bay on the driver side of the firewall, near the brake master cylinder. Fill the reservoir with DOT 3 brake fluid. Do not allow the reservoir to run dry at any time during the bleeding process.
Locate the clutch slave cylinder. It will be bolted to the clutch housing. Locate the small bleeder screw near where the hydraulic hose connects to the slave cylinder.
Connect a length of clear plastic tube to the bleeder screw.
Open the slave cylinder bleeder screw, by turning it counterclockwise. Have an assistant pump the clutch pedal until clean brake fluid seeps out of the bleeder screw. Then close the bleeder screw. Make sure the clutch master cylinder does not run dry.
Have the assistant pump the clutch pedal a few times and hold it against the floor. While the pedal is held against the floor, open the bleeder screw and allow the some fluid to seep out. Close the bleeder screw before releasing the clutch pedal.
Repeat the process listed in the step above and watch the fluid seeping out of the slave cylinder. The clutch is fully bled when there are no more air bubbles in the fluid seeping out of the slave cylinder. You will be able to see the bubbles in the clear plastic tubing. Do not allow the clutch master cylinder to run dry at any point.
Lower the vehicle.