SUBJECT : TORQUE CONVERTER VIBRATION

No: TSB-03-23-006

DATE: October, 2003

MODEL: See below

CIRCULATE TO:

[ ] GENERAL MANAGER

[X] PARTS MANAGER

[X] TECHNICIAN

[X] SERVICE ADVISOR

[X] SERVICE MANAGER

[X] WARRANTY PROCESSOR

[ ] SALES MANAGER

PURPOSE
Some customers may complain of shudder, surge, and/or vibration (possibly intermittent) when driving 35-50 mph (56-80 kph) at steady throttle. This may be due to the breakdown of the A/T fluid, creating a torque converter damper clutch shudder, which can be eliminated by following the procedures in this bulletin.

NOTE
On 1999 Montero Sport rear-wheel-drive models, partial torque converter lock-up also causes rear leaf spring chatter.

AFFECTED VEHICLES
2003 Outlander
2002-2003 Lancer
1997-2002 Mirage
1999-2003 Galant
2000-2003 Eclipse
2001-2003 Eclipse Spyder
1997-2003 Diamante
2001-2003 Montero
1999-2003 Montero Sport

PROCEDURE
NOTE
The information in this bulletin applies to SP-III ATF only. The friction coefficient of SP-III is about 10% lower than that of SP-II, which was used in TSB-01-23-010. Therefore, these specifications are different than those in the previous TSB.

1.Test drive the vehicle to determine whether the shudder/surge/vibration is an engine or transmission concern. Be sure the engine reaches operating temperature. Then turn the engine off and inspect for engine mechanical problems. Check engine base settings and adjust if needed.

a.If the shudder/surge/vibration is an engine concern, refer to Group 11 in the appropriate service manual for diagnosis and repair procedures.

b.If the shudder/surge/vibration is a transmission concern, NOT an engine concern, continue with Step 2.

2.Test drive the vehicle to determine whether the condition occurs during torque converter clutch partial lock-up. Use the scan tool data list to drive within the following parameters. ATF temperature must be 158 degrees F (70 degrees C) or higher.

Note the TCC duty cycle reading when the shudder/surge/vibration occurs.

Vehicle

Year

A/T

A/T Gear

TPS Voltage

Output Shaft Speed

TCC Duty Cycle

TCC Slippage

Outlander

'03

F4A4 W4A4

3rd

0.6 - 1.8

1110 - 2310 rpm

45 - 55 %

40 - 120 rpm

Lancer

'02-'03

F4A4

3rd

0.6 - 1.9

1110 - 2300 rpm

45 - 55 %

40 - 120 rpm

Mirage

'97-'02

F4A4

3rd

0.6 - 1.4

1250 - 1500 rpm

45 - 55 %

40 - 120 rpm

Galant/Eclipse

'99-'03

F4A4

3rd

0.6 - 1.8

1110 - 2310 rpm

45 - 55 %

40 - 120 rpm

F4A5

3rd

0.6 - 1.3

1050 - 2310 rpm

45 - 55 %

40 - 120 rpm

Diamante

'97-'03

F4A5

3rd

0.8 - 1.6

1110 - 2310 rpm

45 - 55 %

40 - 120 rpm

Montero

'01-'03

V4A5

4th

1.1 - 2.6

1470 - 2580

45 - 55 %

40 - 120 rpm

V5A5

5th

1.1 - 2.4

1470 - 2580

45 - 55 %

40 - 120 rpm

Montero Sport

'99-'03

R4A5

3rd

0.7 - 1.6

870 - 1260 rpm

45 - 55 %

40 - 120 rpm

V4A5

3rd

1.0 - 2.5

870 - 1890 rpm

45 - 55 %

40 - 120 rpm

a.If shudder/surge/vibration occurs when the TCC duty cycle is approximately 45% - 55%, the condition may be due to the breakdown of the A/T fluid. Go to Step 3 for repair instructions.

b.If shudder/surge/vibration does NOT occur when the TCC duty cycle is approximately 45% - 55%, diagnose for the following possible causes. Use an electronic vibration analyzer (Kent-Moore J-38792 or equivalant) as described in the "Noise, Vibration and Waterleaks (NVW)" training skill module available through the Mitsubishi Academy.
•Tire vibration
•Front axle vibration
•Damage to A/T internal components
•Transfer case damage

3.If shudder/surge/vibration occurs when the TCC duty cycle is approximately 45% - 55%:

a.Flush the A/T system as described in the "A/T Fluid Replacement" and "Flushing Coolers and Tubes" procedures in Group 23 of the service manual. Backflush the transmission oil cooler when you flush the system. If a flushing tool is not available, refer to TSB-99-23-011 for details on using an aerosol A/T oil cooler flush solution.

b.Refill with new SPIII automatic transmission fluid. It is important to use SPIII to eliminate torque converter damper clutch shudder.

c.With the engine idling and at normal operating temperature, check the ATF temperature by reading "A/T Temperature Sensor" on the scan tool data list. When the ATF temperature is between 158 - 176 degrees F (70-80 degrees C), the ATF level must be just below the "F" mark on the dipstick. Go to Step 4.

d.Test drive to confirm the repair. A small amount of vibration may still exist, which will go away eventually (with 1-60 minutes of driving) as the SPIII works into the clutch material.

(1)If the shudder/surge/vibration condition continues even after the vehicle has been driven for 60 minutes after the repair, or if the customer later returns the vehicle with the same condition, replace the torque converter as described in Group 23 of the appropriate service manual.

WARRANTY INFORMATION
Normal warranty procedures apply.



Mitsubishi Motors North America, Inc.