Tech Tip: Lexus Fifth Gear Shudder – UnderhoodService

Tech Tip: Lexus Fifth Gear Shudder

Models affected: 2004-’05 LX 470 ­vehicles produced before the Production Change Effective VIN: JTJHT00W#53553516

Some 2004 and 2005 model year LX 470 vehicles may exhibit a shudder (or vibration) sensation, usually accompanied by a cyclic droning noise, when lightly accelerating (less than 15% throttle) after the transmission shifts into 5th gear (usually between 35 and 45 mph). This condition may be caused by water entering the transmission breather, contaminating the transmission fluid. The transmission breather has been changed to prevent water intrusion.

Repair Procedure:

1. Remove the automatic transmission with torque converter.

a. Disconnect the breather tube and transfer rear case hose No. 1 from the transmission breather skirt (vent). See Fig. 1.

Fig. 1

b. Remove the transmission with torque converter.

Refer to the Technical Information System (TIS), 2004 or 2005 model year LX 470 Repair Manual; ­Automatic Transmission: Automatic Transmission Unit: Removal.

2. Replace the transmission breather skirt (vent), P/N 35123–60060.

– Remove the bolt and replace the transmission breather skirt (vent). See Fig. 2.

Torque: 12 Nm (122 kgf cm, 8.9 fts.-lbf)

Fig. 2

3. Install the new automatic transmission with the new torque converter, P/N 35010–60A00–84.

Refer to TIS, 2004 or 2005 model year LX 470 ­Repair Manual; Automatic Transmission: Automatic Transmission Unit: Removal.

a. Reconnect the breather tube and transfer rear case hose No. 1 to the transmission breather skirt (vent).

4. Adjust the fluid level in the transmission. Refer to TIS, 2004 or 2005 model year LX 470 Repair Manual; Diagnostics: Automatic Transmission: Pre-Check.

5. Road-test and confirm proper transmission ­operation.

Courtesy of Identifix, Inc.

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