A/T - ZF Noise In Reverse
44-25ZF Automatic Transmission - Noise in Reverse After Cold Start in Cold Weather - Repair Procedure
MODEL
All (4.0L)
DATE
3/95
Sedan (4.0L) Range Up to VIN 720649
XJS (4.0L) Range Up to VIN 194774
ISSUE:
Noise when reverse gear is selected or the vehicle is driven slowly in reverse following a cold start during cold weather.
All 4.0L automatic transmission equipped vehicles up to the VINs listed below may be effected. The noise is caused by air circulating with the cold transmission fluid. The noise has no detrimental effect on the transmission.
Sedan (4.0L) Range UP TO VIN 720649
XJS (4.0L) Range UP TO VIN 194774
Modified transmissions are fitted during production beginning with VINs 720650 (Sedan Range) and 194775 (XJS Range).
ACTION:
If a customer complains of a transmission noise after cold start during cold weather on a vehicle within the VIN range, follow the appropriate procedure described below.
SEDAN (4.0L) RANGE UP TO VIN 720649 - REPAIR PROCEDURE
1. Drive the vehicle until it is at normal operating temperature (10 to 15 miles minimum).
Immediately check the HOT transmission fluid level with the engine idling and the transmission in PARK.
Set the fluid level to the MAX HOT mark on the dipstick.
2. Park the vehicle overnight to become thoroughly cold.
3. Start the vehicle without touching the accelerator. Select reverse and listen for transmission noise. Drive slowly in reverse and listen for transmission noise.
4. If the transmission is noisy in reverse when cold, remove the transmission valve body (valve block) following the instructions in the Service Manual, Section 44.
5. Remove the 4 screws shown in Illustration 1. Replace the existing torque converter control valve with a new control valve (part number NHD 5602AA).
6. Reassemble the transmission. Torque the 13 valve body to transmission screws to 6 lb ft (8 Nm).
7. Drive the vehicle until it is at normal operating temperature (10 to 15 miles minimum). Immediately check the HOT transmission fluid level with the engine idling and the transmission in PARK.
Set the transmission fluid level to the MAX HOT mark on the dipstick.
8. Check the transmission for leaks.
XJS (4.0L) RANGE UP TO VIN 194774 - REPAIR PROCEDURE
1. Install a SERVICE dipstick (part number NHD 4550AA).
2. Drive the vehicle until it is at normal operating temperature (10 to 15 miles minimum). Immediately check the HOT transmission fluid level with the engine idling and the transmission in PARK.
Set the transmission fluid level to the MAX HOT mark on the SERVICE DIPSTICK.
3. Park the vehicle overnight to become thoroughly cold.
4. Start the vehicle without touching the accelerator. Select reverse and listen for transmission noise. Drive slowly in reverse and listen for transmission noise.
5. If the transmission is noisy in reverse when cold, remove the transmission valve body (valve block) following the instructions in the Service Manual, Section 44.
6. Remove the 4 screws shown in Illustration I above. Replace the existing torque converter control valve with a new control valve (part number NHD 5602AA).
7. Reassemble the transmission. Torque the 13 valve body to transmission screws to 6 lb ft (8 Nm).
8. Drive the vehicle until it is at normal operating temperature (10 to 15 miles minimum). Immediately check the HOT transmission fluid level with the engine idling and the transmission in PARK.
Set the transmission fluid level to the MAX HOT mark on the SERVICE DIPSTICK.
9. Check the transmission for leaks.
10. Park the vehicle overnight to become thoroughly cold.
11. Start the vehicle without touching the accelerator. Select reverse and listen for transmission noise. Drive slowly in reverse and listen for transmission noise.
12. If there is no noise, replace the SERVICE DIPSTICK with the original dipstick.
13. If the transmission noise is still unacceptable, remove the automatic transmission, starter ring gear/drive plate assembly and crankshaft adapter following the instructions in the Service Manual, Section 44.
14. Replace the existing components listed below with new components
COMPONENT NEW PART NUMBER QTY
Crankshaft adapter NHE 1425AA 1
Starter ring gear/drive plate assy. NHE 1428AA 1
Spacer NHE 1431AA 1
Bolt JZB 100046 8
Dipstick NHD 4550AB 1
Automatic transmission NHE 4400BA/N 1
IMPORTANT:
The existing valve body MUST be fitted to the new transmission to maintain shift quality and harness compatibility.
The existing dipstick tube MUST be fitted to the new transmission.
A new dipstick (part number NHD 4550AB) MUST be fitted.
Do not use the existing dipstick or the SERVICE DIPSTICK.
15. Drive the vehicle until it is at normal operating temperature (10 to 15 miles minimum). Immediately check the HOT transmission fluid level with the engine idling and the transmission in PARK
16. Set the fluid level to the MAX HOT level on the new dipstick.
17. Check the transmission for leaks.
PARTS INFORMATION:
SEDAN RANGE VEHICLES
DESCRIPTION PART NUMBER QTY
Transmission torque converter control valve NHD 56O2AA 1
XJS RANGE VEHICLES
DESCRIPTION PART NUMBER QTY
Transmission torque converter control valve NHD 56O2AA 1
Service dipstick NHD 455OAA 1
Automatic transmission NHE 4400BA/N 1
Crankshaft adapter NHE 1425AA 1
Starter ring gear/drive plate assy. NHE 1428AA 1
Spacer NHE 1431AA 1
Bolt JZB 100046 8
Dipstick NHD 4550AB 1
WARRANTY INFORMATION: