Canada - A/T - Clunk/Pop/Thunk On Acceleration Or Stopping

Bulletin
3121

Issue Date
March 27, 2009

Market
Canada

Title:
CLUNK NOISE AT LOW SPEEDS WHEN STOPPING OR TURNING

Component
AUTOMATIC TRANSMISSION

Models
'05-07 Sequoia; '05-'06 Tundra

INTRODUCTION:
Some customers of 2WD 2005 - 2007 model year Sequoia and 2005 - 2006 model year Tundra vehicles may complain about a clunk, thunk, or pop noise from the vehicle that is most commonly heard when stopping, accelerating from a stop, or turning at low speeds. The source of the noise has been identified as the joint between the rear transmission mount and the frame crossmember.The transmission mount has been redesigned to prevent this. Use the following repair procedure to address customer concerns.







APPLICABILITY:







WARRANTY INFORMATION:







PARTS INFORMATION:







REQUIRED TOOLS & EQUIPMENT:

NOTE
- A mechanic's stethoscope or similar tool may be used in place of ChassisEAR(TM).

REPAIR PROCEDURE:







1. Place the vehicle on a lift and install ChassisEAR(TM) (or equivalent) on the following components to help isolate the source of the noise (see Figure 1):
- On frame crossmember No. 3.
- On rear transmission mount above rubber section of mount or on transmission extension housing assembly.

2. Test drive the vehicle and duplicate the noise.
3. With ChassisEAR(TM) installed, the noise should be very loud from the frame crossmember No. 3 pickup location and NOT heard on the rear transmission mount above the rubber section of the mount.

Is the noise loudest when ChassisEAR(TM) has frame crossmember No. 3 selected?
- YES - Go to step 4.
- NO - This TSB does NOT apply. Continue using ChassisEAR(TM) to identify the source of the noise and diagnose per the Repair Manual.

4. Replace the rear transmission mount, frame crossmember No. 3, and 4 bolts retaining the transmission mount to frame crossmember No. 3.
A. Place the vehicle on a lift.

HINT
Use a transmission jack and underhoist stand to lift and support the transmission assembly during the next 5 steps.







B. Remove the 4 bolts retaining the transmission to the rear transmission mount







C. Remove the 4 bolts retaining the frame crossmember No. 3 to the frame assembly and remove the frame crossmember No. 3 assembly with rear transmission mount from the vehicle.

NOTE
Do NOT torque any of the bolts in steps D through F until ALL the bolts in steps D through F have been started.







D. Install the NEW rear transmission mount (insulator, engine mounting rear) to the NEW frame crossmember No. 3 using the 4 NEW bolts.

Torque: 65 N-m (660 kgf-cm, 48 ft-lbf)

E. Install the NEW rear transmission mount (insulator, engine mounting rear) to the NEW frame crossmember No. 3 using the 4 NEW bolts.

Torque: 30 N-m (300 kgf-cm, 22.1 ft-lbf)







NOTE
The torque value for these 4 bolts has been increased.







F. Install the NEW frame crossmember No. 3 into the frame and tighten the 4 bolts.

Torque: 72 N-m (734 kgf-cm, 53 ft-lbf)







G. Tighten all the bolts in steps D through F.
Tighten the bolts retaining the NEW rear transmission mount (insulator, engine mount rear) to the NEW frame crossmember No. 3 in the order shown in Figure 7. Tighten bolt 1, then 2, then 3, then 4.

Torque: 30 N-m (300 kgf-cm, 22.1 ft-lbf)

Then tighten bolt 1 once again.

Torque: 30 N-m (300 kgf-cm, 22.1 ft-lbf)

5. Test drive the vehicle and confirm the noise is eliminated.

NOTE:
Issue of this Technical Service Bulletin is to ensure that proper repair information is available. IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR. Normal provisions of the formal warranty policy, as applicable, will apply.