Hummer H2. Manual - part 2399

Dry the plates and inspect the plates for the following conditions:

z

Pitting  

z

Flaking  

z

Delamination - splitting or separation of bonded clutch material  

z

Wear  

z

Glazing  

z

Cracking  

z

Charring  

z

Chips or metal particles embedded in the lining  

Replace a composition plate which shows any of these conditions. 

Steel Plates 

Wipe the plates dry and check the plates for heat discoloration. If the surfaces are smooth, even if color smear is 
indicated, you can reuse the plate. If the plate is discolored with heat spots or if the surface is scuffed, replace 
the plate. 

Causes of Burned Clutch Plates 

The following conditions can result in a burned clutch plate: 

z

Incorrect usage of clutch or apply plates  

z

Engine coolant or water in the transmission fluid  

z

A cracked clutch piston  

z

Damaged or missing seals  

z

Low line pressure  

z

Valve body conditions 

{

The valve body face is not flat.  

{

Porosity is between channels.  

{

The valve bushing clips are improperly installed.  

{

The checkballs are misplaced.  

z

The Teflon(R) seal rings are worn or damaged.  

ENGINE COOLANT/WATER IN TRANSMISSION 

If antifreeze or water has entered the transmission, perform the following:

NOTE:

The antifreeze or water will deteriorate the seals, gaskets and the glue that 
bonds the clutch material to the pressure plate. Both conditions may cause 
damage to the transmission.

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle - 4L60-E/4L65-E (Troubleshooting)

  

1. Disassemble the transmission.  

2. Replace all of the rubber type seals (the coolant will attack the seal material which will cause leakage).  

3. Replace the composition-faced clutch plate assemblies (the facing material may separate from the steel 

center portion).  

4. Replace all of the nylon parts (washers).  

5. Replace the torque converter.  

6. Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.  

7. Flush the cooler lines after the transmission cooler has been properly repaired or replaced.  

FLUID LEAK DIAGNOSIS 

General Method 

1. Verify that the leak is transmission fluid.  

2. Thoroughly clean the suspected leak area.  

3. Operate the vehicle for 24 km (15 mi), or until normal operating temperatures are reached.  

4. Park the vehicle over clean paper or cardboard.  

5. Shut OFF the engine.  

6. Look for fluid spots on the paper.  

7. Make the necessary repairs.  

Powder Method 

1. Thoroughly clean the suspected leak area with solvent.  

2. Apply an aerosol type powder, such as foot powder, to the suspected leak area.  

3. Operate the vehicle for 24 km (15 mi), or until normal operating temperatures are reached.  

4. Shut OFF the engine.  

5. Inspect the suspected leak area.  

6. Trace the leak path through the powder in order to find the source of the leak.  

7. Make the necessary repairs.  

Dye and Black Light Method 

A fluid dye and black light kit is available from various tool manufacturers. 

1. Follow the manufacturer's instructions in order to determine the amount of dye to use.  

2. Detect the leak with the black light.  

3. Make the necessary repairs.  

Find the Cause of the Leak 

Pinpoint the leak and trace the leak back to the source. You must determine the cause of the leak in order to 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle - 4L60-E/4L65-E (Troubleshooting)

  

repair the leak properly. For example, if you replace a gasket, but the sealing flange is bent, the new gasket will 
not repair the leak. You must also repair the bent flange. Before you attempt to repair a leak, check for the 
following conditions, and make repairs as necessary: 

Gaskets 

z

Fluid level/pressure is too high  

z

Plugged vent or drain-back holes  

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Improperly tightened fasteners  

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Dirty or damaged threads  

z

Warped flanges or sealing surface  

z

Scratches, burrs, or other damage to the sealing surface  

z

Damaged or worn gasket  

z

Cracking or porosity of the component  

z

Improper sealant used, where applicable  

z

Incorrect gasket  

Seals 

z

Fluid level/pressure is too high  

z

Plugged vent or drain-back holes  

z

Damaged seal bore  

z

Damaged or worn seal  

z

Improper installation  

z

Cracks in component  

z

Manual or output shaft surface is scratched, nicked, or damaged  

z

Loose or worn bearing causing excess seal wear  

Possible Points of Fluid Leaks 

Transmission Oil Pan 

z

Incorrectly tightened oil pan bolts  

z

Improperly installed or damaged oil pan gasket  

z

Damaged oil pan or mounting face  

z

Incorrect oil pan gasket  

Case Leak 

z

Damaged or missing fill tube seal  

z

Mislocated fill tube bracket  

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle - 4L60-E/4L65-E (Troubleshooting)

  

z

Damaged vehicle speed sensor seal  

z

Damaged manual shaft seal  

z

Loose or damaged oil cooler connector fittings  

z

Worn or damaged propeller shaft oil seal  

z

Loose line pressure pipe plug  

z

Porous casting warped torque converter housing  

Leak at the Torque Converter End 

z

Converter leak in the weld area  

z

Converter seal lip cut. Check the converter hub for damage  

z

Converter seal bushing moved forward and damaged  

z

Converter seal garter spring missing from the seal  

z

Porous casting of the transmission case or the oil pump  

Leak at the Vent Pipe or the Fluid Fill Tube 

z

Overfilled system  

z

Water or coolant in the fluid. The fluid will appear milky  

z

Transmission case porous  

z

Incorrect fluid level indicator  

z

Plugged vent  

z

Drain-back holes plugged  

z

Mispositioned oil pump to case gasket, if equipped 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle - 4L60-E/4L65-E (Troubleshooting)