Vehicle - Body Vibration
No: TSB-01-42A-014DATE: December, 2001
MODEL: 1997-02 Montero Sport
SUBJECT:
VEHICLE BODY VIBRATION
This bulletin supercedes TSB-00-42A-003, issued April, 2000, to update affected vehicles and include additional possible repairs New and revised information are indicated by -->.
PURPOSE
The procedures in this bulletin address customer body vibration complaints. To minimize the vibration condition, all inspection procedures in this bulletin should be followed.
IMPORTANT
Customers should be advised that sport-utility vehicles are designed for more rugged operation than passenger cars, and will exhibit different ride characteristics. Some body shake is normal on this type of vehicle, typically felt in the seat bottom and in the floor when driving on certain road surfaces.
AFFECTED VEHICLES
--> 1997-2002 Montero Sport models. Refer to the applicable repair steps for model year and drive type shown.
PROCEDURE
1. It is critical to determine the specific nature of the customer's complaint. Test drive the vehicle to verify the customer's complaint. If possible, this should be done with the customer and the DPSM with you in the vehicle during the test drive.
2. Review the vehicle repair history to determine what, if any, parts have already been replaced and/or parts that need to be ordered for this complaint. Possible previous parts replacement could be:
^ Intermediate steering shaft (p/n MR475226)
^ (2WD Only) Rear propeller shaft - Refer to part numbers.
^ (2WD Only) Transmission mount - Refer to part numbers.
3. Check the vehicle's ride height as follows. For best results, perform this check with the vehicle on a drive-on rack.
a. To settle the suspension, rock the vehicle back and forth a few times. Do this with the transmission in "D" or first gear, and again in Reverse.
b. Measure the clearance between the bump stopper and bump stopper bracket (measurement "A" in the illustration). The clearance should be 20 mm (0.78 in.).
Measure the bump stopper height (measurement "B" in the illustration). If "B" is less than 50 mm (2 in.), "A" should be more than 20 mm (0.78 in.) by the same amount. Example: If "B" is 40 mm, adjust "A" to 30 mm.
c. If not within specifications, adjust the clearance by tightening or loosening the adjusting nut. The clearance will change by about 1 mm per rotation.
4. (2WD Only) Check for a cracked appearance on the propeller shaft center bearing rubber mount. Also check to see if the shaft is centered in the mount.
a. If no cracking is found and the center bearing rubber mount is centered, inspect for undercoating overspray on the face of the propeller shaft. Completely remove the undercoating from the propeller shaft face with a heavy-duty degreaser.
b. If any cracking is found or if the center bearing rubber mount is not centered, replace the rear propeller shaft, using the appropriate part listed in the PARTS INFORMATION section of this bulletin. (Improved design center bearing mounts have been used in vehicle production since 10/99.)
IMPORTANT
Before removing the old propeller shaft, place a mating mark on the differential companion flange at the location of the propeller shaft part number decal. Install the new propeller shaft with its part number decal aligned with the mating mark.
5. (2WD Only) Inspect the transmission mount. If there is a paint mark and/or the letter "B" applied to the rubber portion as shown, it is an improved design transmission mount and does not need to be replaced unless damage is found. Improved design mounts have been used in vehicle production since 10/98.
If no paint mark and/or the letter "B" is found, replace the mount with the appropriate part in the PARTS INFORMATION section of this bulletin.
6. Check the front hub end play:
NOTE:
A quick check for free play can be made by grasping the wheel and tire assembly and wobbling it. If you hear a clicking noise or observe any movement, end play is excessive and should be adjusted by following Step 6b below.
a. Install a dial gauge as shown. Move the hub in the axial direction (in and out) and measure how far the front wheel bearing moves.
If the hub moves 0.05 mm or more, end play is excessive. Go to Step b below to adjust end play.
b. Use special tool MB990954 to tighten the jam nut as follows:
a. Tighten the jam nut to 127-196 Nm (94-145 ft/lb), then turn the front hub assembly to run in the bearings.
b. Loosen the nut completely.
c. Re-tighten to 25 Nm (18 ft/lb), then loosen approximately 30 degrees.
On 4WD models, measure the hub rotary sliding resistance (hub rotation breakaway torque), using a spring scale as shown. The sliding resistance specification is 4-19 N (0.9-4.3 lbs.).
If the rotary sliding resistance is not within the specification, use special tool MB990954 to tighten or loosen the jam nut as needed.
7. For models produced before 10/29/98 VIN XP028706), refer to TSB-99-37A-001 for intermediate steering shaft replacement and steering gear backlash adjustment.
8. Remove the wheel and tire assemblies.
9. Check the brake disc thickness and and run-out. Refer to Group 35 in the appropriate service manual.
NOTE:
If the brake discs were previously re-surfaced and the front hub end play was not correct in Step 6, the discs may be out of specification.
10. Worn tires could be a source of steering wheel vibration. Check tire pressure (should be 26 psi when cold) and inspect for tire wear on all four tires. Particularly check for evidence of tire cupping, indicated by dish-shaped worn spots or bald spots on the tire edges.
Inform the customer of the importance of tire rotation at regular intervals. Suggest tire rotation every 6,000 miles or more frequently as needed for this type of vehicle.
11. Check wheel balance on all four wheels. Proper wheel balance is CRITICAL in reducing body vibration. Refer to TSB-00-31-001 REV for wheel balance adjustment information using hub adapter special tool MB991820.
If possible, perform wheel balance on a Hunter 9700 wheel balancer. Record the radial force variation for each wheel and tire assembly on the repair order. Mark the location where the wheel and tire assembly was installed on the vehicle on the inside sidewall, for possible future diagnosis.
12. Reinstall the wheel and tire assemblies.
13. Test drive the vehicle to confirm if the vibration is minimized. If the vibration is not minimized, go to Step 14.
14. --> If the vibration is not minimized:
3.0L and 2.4L Models:
Replace all of the engine mounts and stopper brackets. Refer to the PARTS INFORMATION section of this bulletin for replacement part numbers.
Check for interference between the engine mount and the stopper bracket. Verify whether the interference is at the rear or the front of the stopper bracket. Install the appropriate engine mounts and stopper brackets listed in the PARTS INFORMATION section.
3.5L Models:
Inspect the engine mounts for a cut-out at the center portion of the engine mount as shown.
a. If the engine mounts do NOT have a cut-out, replace with improved mounts listed in the PARTS INFORMATION section of this bulletin.
b. If the center portion of the engine mounts have a cut-out:
^ Inspect the engine mounts for signs of deterioration (such as sagging, bulging, and/or small cracks in rubber). Replace as necessary.
^ Inspect the position of the mounts. The mount should be at the center of the stopper bracket as shown. If necessary, adjust the mount to achieve this position.
15. If the vibration continues, loosen all ten of the body mounts. Then, with the help of one or two other persons, shake the vehicle body. Then re-torque the body mounts to 27-31 Nm (20-23 ft/lbs).
16. Test drive the vehicle to confirm if the vibration is minimized. If the vibration has not decreased to the customer's satisfaction, discuss this vehicle's condition with your District Parts and Service Manager.
PARTS INFORMATION
WARRANTY INFORMATION
Normal warranty procedures apply.