Delayed Engagement Into D, 1ST Gear Slip When Starting Off
DELAYED ENGAGEMENT COMPLAINT DESCRIPTION:
After engaging shift selector into transmission range "D" transmission seem to momentarily freewheel during throttle application. Drive then engages with harsh shift quality. This condition is worse when cold.
On all delayed engagement complaints, customers should be advised to wait for the selected gear to fully engage before accelerating. Refer to editions of Owners Manual (section Driving).
A. CAUSE:
Figure 1:
Excessive Band 2 release clearence together with B 2 piston (1) application pressure leaking past B2 piston teflon seal ring (T-form ring, item 2, Figure 1) at transmission case bore.
A. REMEDY:
Install improved B2 piston teflon seal ring (T-form ring) and adjust Band 2 release clearence to minimum specification 5.5 mm.
WORKING INSTRUCTIONS
NOTE: This remedy is performed with transmission installed in vehicles.
1. Raise vehicle on hoist.
2. Remove large underbody encapsulation panel (diesel model only).
3. Support rear muffler with adjustable support, remove exhaust hanger and partial lower exhaust system.
4. Support transmission with transmission jack.
5. Remove transmission mounting plate.
6. Remove tunnel cross-brace at front of catalyst heat shield.
7. Remove heat shield above catalyst.
8. Disconnect O2 sensor harness as nessary (gasoline models only).
9. Carefully lower exhaust system and support at rear mount with fan belt/strap.
10. Lower transmission, remove transmission jack.
11. Remove transmission oil pan drain plug and drain transmission fluid.
12. Remove transmission oil pan.
13. Remove transmission oil filter.
14. Remove valve body and large intermediate plate with gasket
15. Measure and record Band 2 release clearance.
NOTE:
- B2 piston is hydraulically pressurized to apply and hydraulically pressurized to release.
- Band 2 release clearance is the difference between Band 2 being fully clamped (applied) and fully released (Band 2 pressed outward so that B2 piston contacts cover).
SERVICE TIP
- Extremely accurate measurement and adjustment of Band 2 release clearance to minimum specifications is of equal importance as replacement of B2 piston T-form ring.
Figure 2:
- Inside calipers (Figure 2), such as Sears Craftsman tool no. 38575 or Mitutoyo tool no. 950-232, work well for this purpose.
- Inside calipers allow precise measurement that can then be transferred to vernier calipers.
16. Press in B2 piston cover by hand and remove snap-ring.
17. Using a long bar, press transmission towards drivers side of vehicle and remove B2 piston cover and B2 piston.
NOTE: Retrieve Band 2 adjustment pin from bore.
18. Remove B2 piston white teflon T-form ring by rolling-off by hand or cutting with a knife.
19. Install new B2 piston T-form ring. part no.'s 140 277 01 55 or 202 277 00 55, by carefully and evenly installing by hand from pressure application side of piston (indicated by "1", Figure 1).
NOTE:
- Avoid stretching or distorting shape of T-form ring.
- Warm new T-form ring in 80°C warm water for approx. 5 minutes to permit easier installation.
20. Measure and record length, of adjustment pin that was removed from B2 piston bore in step 17.
Band 2 Adjustment Pins:
21. Select replacement adjustment pin as necessary to achieve Band 2 release clearance of 5.0 to 5.5 mm. Refer to the following example:
- Band 2 release clearance measured in step 15 7.4 mm
- Band 2 release clearance nominal value 5.0 mm
- Adjustment difference to be compensated by installation of longer adjustment pin 2.4 mm
- Length of adjustment pin removed in stop 17 47.2 mm
- Add necessary adjustment 2.4 mm
- Necessary length of adjustment pin to achieve correct Band 2 release clearance 49.6 mm
22. Install Band 2 adjustment pin into socket of Band 2.
23. Press transmission towards drivers side.
Install B2 piston into bore observing critical attention to not damage or told lip seal positioned in transmission case.
Verify correct position of Band 2 adjustment pin.
24. Verify correct position of B2 piston cover O-ring in -transmission case.
25. Install B2 piston cover and snap-ring.
26. Recheck Band 2 release clearance adjustment as performed in step 15 to verify correct release clearance of 5.0 - 5.5 mm. Repeat adjustment procedures if necessary.
NOTE: Under no circumstances adjust B2 release clearance below 4.8 mm (ie: increased transmission friction, accelerated wear, loss in fuel economy).
27. Reinstall large intermediate plate with gasket, valve body, transmission oil filter and transmission oil pan.
Tightening Torque:
8 Nm Valve body and large intermediate plate
8 Nm Transmission oil pan bolts
14 Nm Transmission oil pan drain plug
28. Raise transmission with transmission jack and reinstall transmission rear mounting plate.
Tightening Torque:
25 Nm M8 Bolts
4O Nm M10 Bolts
29. Reinstall tunnel cross-brace.
30. Reinstall heat shield above catalyst.
31. Raise exhaust system and secure with exhaust hangers.
Part Information:
Production Phase-in Information:
32. Reconnect O2 sensor connectors and resecure O2 sensor harness in clips (gasoline models only).
33. Lower vehicle from hoist. Correct transmission fluid level, idle engine and inspect for leaks.
34. Reinstall underbody encapsulation panel (diesel models only).
35. Road test vehicle. Recheck transmission fluid level and inspector leaks.
NOTE: This topic is cross referenced in Delayed Engagement Into Reverse - 722.4 only. Delayed Engagement Into Reverse - 722.4
B.
The following repair procedure should be performed ONLY if Delayed Engagement Into Drive complaint still exists after optimizing B2 piston T-form ring and Band 2 release clearence as described in A Remedy of this topic.
B. CAUSE: Reaction time of Accumulator switching on (53) is too long.
B. REMEDY:
- Remove valve body and carefully disassemble to remove valve body small intermediate plate.
Figure 3:
- Enlarge bore 14 of small intermediate plate (illustration inset, Figure 3) to exactly 1.2 mm.
- This modification requires extreme precision.
- Failure to enlarge bore 14 to exactly 1.2 mm can result in delayed engagement becoming harsh engagement.