Low and Reverse Clutch Overhaul. GMC Truck Yukon XL Denali 2008

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2008 🢒 Yukon XL Denali 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 6L50/6L80/6L90 🢒 Low and Reverse Clutch Overhaul

Low and Reverse Clutch Overhaul 6L80

Table 1:	Low and Reverse Clutch Plate Removal
Table 2:	Low and Reverse Clutch Piston Removal
Table 3:	Low and Reverse Clutch Piston Installation
Table 4:	Low and Reverse Clutch Plate Installation

Low and Reverse Clutch Plate Removal

Low and Reverse Clutch Plate Removal

Callout	Component Name
1	Low and Reverse Clutch Backing Plate Retaining Ring
2	Low and Reverse Clutch Backing Plate
3	Low and Reverse Clutch Plate Assembly (Qty: 5)
4	Low and Reverse Clutch Plate (Qty: 5)
5	Low and Reverse Clutch (Waved) Plate

Low and Reverse Clutch Piston Removal

Low and Reverse Clutch Piston Removal

Callout	Component Name
1	Low and Reverse Clutch Spring Retaining Ring Notice: Ensure the DT 47779 contacts the sprag assembly and not the sprag retaining ring. Damage to the sprag may result. Special Tool DT 47779 Clutch Spring Compressor
2	Low Clutch Sprag Assembly
3	Low and Reverse Clutch Spring
4	Low and Reverse Clutch Piston Assembly Tip It may be necessary to apply air to the apply passage in order to unseat the piston.
5	Low Clutch Sprag Seal Notice: Refer to Seal Reuse Notice in the Preface section.

Low and Reverse Clutch Piston Installation

Low and Reverse Clutch Piston Installation

Callout

Component Name

Low and Reverse Clutch Piston Assembly

Tip
Lubricate the inner and outer sealing surfaces of the piston assembly with automatic transmission fluid (ATF) in order to ease installation into the center support assembly.

Low Clutch Sprag Seal

Notice: Refer to Seal Reuse Notice in the Preface section.

Tip
Apply ATF to the DT 47780 to ease seal installation.

Special Tool

DT 47780 Low Clutch Sprag Seal Cone

Low and Reverse Clutch Spring

Notice: Ensure the spring tabs are facing up during installation. Failure to do so may cause damage to the clutch assembly.

Low Clutch Sprag Assembly

Tip

•	Verify that the low clutch sprag is operating correctly. Refer to the illustration for proper freewheel direction.

•	Ensure the missing splines on the sprag assembly are aligned with the missing splines on the center support hub.

Low and Reverse Clutch Spring Retaining Ring

Notice: Ensure the DT 47779 contacts the sprag assembly and not the sprag retaining ring. Damage to the sprag may result.

Notice: The retaining ring gap must be aligned with the 3 missing splines on the center support hub. Failure to do so may cause damage to the clutch assembly.

Special Tools

•	DT 47778-1 Low Clutch Sprag Retaining Ring Cone

•	DT 47778-2 Low Clutch Sprag Retaining Ring Pusher

•	DT 47779 Clutch Spring Compressor

Low and Reverse Clutch Plate Installation

Low and Reverse Clutch Plate Installation

Callout	Component Name
1	Low and Reverse Clutch (Waved) Plate
2	Low and Reverse Clutch Plate (Qty: 5)
3	Low and Reverse Clutch Plate Assembly (Qty: 5)
4	Low and Reverse Clutch Backing Plate
5	Low and Reverse Clutch Backing Plate Retaining Ring Tip Apply air to verify proper installation of all low and reverse clutch components.

Low and Reverse Clutch Overhaul 6L90

Table 1:	Low and Reverse Clutch Plate Removal
Table 2:	Low and Reverse Clutch Piston Removal
Table 3:	Low and Reverse Clutch Piston Installation
Table 4:	Low and Reverse Clutch Plate Installation

Low and Reverse Clutch Plate Removal

Low and Reverse Clutch Plate Removal

Callout	Component Name
1	Low and Reverse Clutch Backing Plate Retaining Ring
2	Low and Reverse Clutch Backing Plate
3	Low and Reverse Clutch Plate Assembly (Qty: 6)
4	Low and Reverse Clutch Plate (Qty: 6)
5	Low and Reverse Clutch (Waved) Plate

Low and Reverse Clutch Piston Removal

Callout	Component Name
1	Low and Reverse Clutch Spring Retaining Ring Notice: Ensure the DT 47779 contacts the sprag assembly and not the sprag retaining ring. Damage to the sprag may result. Special Tool DT 47779 Clutch Spring Compressor
2	Low Clutch Sprag Assembly
3	Low and Reverse Clutch Spring
4	Low and Reverse Clutch Piston Assembly Tip It may be necessary to apply air to the apply passage in order to unseat the piston.
5	Low Clutch Sprag Seal Notice: Refer to Seal Reuse Notice in the Preface section.

Low and Reverse Clutch Piston Installation

Callout

Component Name

Low and Reverse Clutch Piston Assembly

Tip
Lubricate the inner and outer sealing surfaces of the piston assembly with automatic transmission fluid (ATF) in order to ease installation into the center support assembly.

Low Clutch Sprag Seal

Notice: Refer to Seal Reuse Notice in the Preface section.

Tip
Apply ATF to the DT 47780 to ease seal installation.

Special Tool

DT 47780 Low Clutch Sprag Seal Cone

Low and Reverse Clutch Spring

Notice: Ensure the spring tabs are facing up during installation. Failure to do so may cause damage to the clutch assembly.

Low Clutch Sprag Assembly

Tip

•	Verify that the low clutch sprag is operating correctly. Refer to the illustration for proper freewheel direction.

•	Ensure the missing splines on the sprag assembly are aligned with the missing splines on the center support hub.

Low and Reverse Clutch Spring Retaining Ring

Notice: Ensure the DT 47779 contacts the sprag assembly and not the sprag retaining ring. Damage to the sprag may result.

Notice: The retaining ring gap must be aligned with the 3 missing splines on the center support hub. Failure to do so may cause damage to the clutch assembly.

Special Tools

•	DT 47778-1 Low Clutch Sprag Retaining Ring Cone

•	DT 47778-2 Low Clutch Sprag Retaining Ring Pusher

•	DT 47779 Clutch Spring Compressor

Low and Reverse Clutch Plate Installation

Low and Reverse Clutch Plate Installation

Callout	Component Name
1	Low and Reverse Clutch (Waved) Plate
2	Low and Reverse Clutch Plate (Qty: 6)
3	Low and Reverse Clutch Plate Assembly (Qty: 6)
4	Low and Reverse Clutch Backing Plate
5	Low and Reverse Clutch Backing Plate Retaining Ring Tip Apply air to verify proper installation of all low and reverse clutch components.