Drivetrain - Rear Differential Whine/Howl At 50-70 MPH
T-SB-0076-08May 29, 2008
Rear Differential Whine or Howling Noise at Highway Speeds
Service Category
Drivetrain
Section
Axle/Differential
Market
USA
Applicability
The information contained in this TSB supersedes TSB No. DL001-08.
^ Parts Information has been updated (parts quantity has been revised for RR Floor Silencer Pad).
^ Applicability has been updated (2008 model year has been added).
TSB No. DL001-08 is Obsolete and any printed versions should be discarded. Be sure to review the entire content of this service bulletin before proceeding.
Introduction
Some customers may complain of an excessive whine or howling noise from the rear of the vehicle between 50 - 70 mph (80 - 113 km/h) when lightly accelerating or decelerating. Use the following repair procedure to address this concern.
Warranty Information
^ This repair is covered under the Toyota Powertrain Warranty. This warranty is in effect for 60 months or 60,000 miles, whichever occurs first, from the vehicle's in-service date.
^ Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Parts Information
Required Tools & Equipment
Repair Procedure
1. Replace the rear differential assembly.
Refer to the Technical Information System (TIS) applicable model and model year Repair Manual:
^ 2005 Tacoma:
Drivetrain - Axle/Differential -
^ 2006 Tacoma:
Drivetrain - Axle/Differential - "Differential: Rear Differential Carrier Assembly: Removal and Installation
^ 2007 Tacoma:
Drivetrain - Axle/Differential - "Differential: Rear Differential Carrier Assembly: Removal and Installation"
^ 2008 Tacoma:
Drivetrain - Axle/Differential - "Differential: Rear Differential Carrier Assembly: Removal and Installation"
2. Remove the seat assemblies (bench or bucket).
Refer to the TIS applicable model and model year Repair Manual:
2005 Tacoma:
^ Vehicle Interior - Seat - "Seat Assy (Bench Seat Type): Overhaul"
^ Vehicle Interior - Seat - "Front Seat Assy LH (Separate Seat Type): Overhaul"
^ Vehicle Interior - Seat - "Front Seat Assy RH (Separate Seat Type): Overhaul"
2006 Tacoma:
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Seat Type Front Passenger Side): Removal"
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Seat Type Driver Side): Removal"
2007 Tacoma:
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Seat Type Front Passenger Side): Removal"
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Driver Side): Removal"
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Bench Seat Type): Removal"
2008 Tacoma:
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Seat Type Front Passenger Side): Removal"
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Separate Seat Type Driver Side): Removal"
^ Vehicle Interior - Seat - "Seat: Front Seat Assembly (for Bench Seat Type): Removal"
3. For bucket seat type ONLY: Remove the center console. If bench seat type, go to step 4.
For more information, refer to the TIS, applicable model and model year Repair Manual:
^ 2005 Tacoma:
Vehicle Interior - Interior Panels/Trim - "Instrument Panel Sub-Assy: Replacement"
^ 2006, 2007 or 2008 Tacoma:
Vehicle Interior - Interior Panels/Trim - "Instrument Panel: Instrument Panel Safety Pad: Removal"
^ For automatic transmission on separate (bucket) seat type:
Remove the console upper rear panel sub-assembly.
1. Remove the shift knob.
2. Disengage the 6 clips and 1 claw and remove the console upper rear panel sub-assembly.
^ For manual transmission on separate (bucket) seat type:
Remove the console upper rear panel sub-assembly by disengaging the 4 clips and 1 claw.
^ For separate (bucket) seat type:
Remove the rear console box assembly.
1. Remove the console box carpet.
2. Remove the 2 screws and 2 bolts.
3. Disengage the 4 claws and remove the rear console box assembly.
For more information, refer to the TIS, applicable model and model year Repair Manual:
^ 2005 Tacoma:
Vehicle Interior - Interior Panels/Trim - "Instrument Panel Sub-Assy: Replacement"
^ 2006, 2007, or 2008 Tacoma:
Vehicle Interior - Interior Panels/Trim - "Instrument Panel: Instrument Panel Safety Pad: Removal"
4. Remove the LH and RH front door scuff plates.
5. Unbolt the lower seat belt anchor mount on both sides of vehicle.
6. Pull back the carpeting to reveal approximately 2 feet (0.6 m) of floorboard.
7. Install the rear floor silencer sheet.
Silencer sheets should be positioned as shown with 2 silencer sheets doubled up in each location.
Use 3M General Purpose Adhesive Cleaner (or equivalent) to clean the area of the floorboard where the silencer sheets will be located.
The centerline of the truck is indicated by the small metal dimple in the floorpan (see Figure 7).
8. Install the rear floor silencer pad.
The silencer pad should be located 12.5 mm (0.5 in.) forward of the rear wall of the cab and attached to the floor using the double-sided adhesive tape along the rear edge of the sheet (closest to the rear wall of the cab).
See Figure 8 for the position of the silencer pad.
9. Reassemble vehicle in reverse order of disassembly.