OBJECTIVES

2. OBJECTIVES After studying Chapter 11, the reader should be able to: • Check the fluid level in an automatic transmission. • Check automatic transmission fluid condition. • Change the fluid in an automatic transmission. • Adjust manual shift linkage. • Adjust throttle linkage. • Adjust a band in an automatic transmission. • Complete the SAE tasks related to transmission/transaxle maintenance and adjustment (see Appendix A).

3. INTRODUCTION • Automatic transmissions and transaxles can operate properly for many miles while being totally neglected. • Some that fail could have had a longer service life if they had been properly maintained. • Several surveys of transmission shops have produced responses that over 80% of transmission failures were the result of neglecting to change the fluid. Newer transmissions require very little maintenance.

4. FLUID CHECKS • The operator of a vehicle should check the fluid level in an automatic transmission periodically. • A good time is right after every engine oil change. • If the level is low, fluid of the correct type should be added. • It usually takes one pint (0.5 L) to move the fluid level from low to the full mark on the dipstick.

5. FIGURE 11-1 Most dipsticks have fluid-level markings for various temperatures. The vehicle should not be operated if the level is below the underfill or above the overfill marks. FLUID CHECKS

6. FLUID CHECKS • To check transmission fluid, you should: • To check sealed transmission fluid level, you should

7. FIGURE 11-2 When checking the fluid level, the engine should be at idle speed, the fluid hot, and the gear selector should be positioned as required by the vehicle manufacturer. Note the fluid level and compare it with dipstick markings. It is also a good practice to note any unusual fluid color or odor. FLUID CHECKS

8. FIGURE 11-3 Fluid level on sealed units (without a dipstick) is checked by removing the level plug, which can be mounted in the bottom or side of the pan or in the case. FLUID CHECKS

9. FIGURE 11-4 Some transaxle differentials have a plug to allow checking of the fluid level in the final drive section. (Courtesy of Chrysler Corporation) FLUID CHECKS • Transaxle Final Drives and Differentials • Fluid Condition

10. FIGURE 11-5 A useful chart for checking fluid level and condition. (Reprinted with permission of General Motors) FLUID CHECKS

11. FIGURE 11-6 Fluid condition can be checked by placing a sample on clean, white, absorbent paper (a). Clean fluid will spread out and leave only a wet stain (b). Dirty fluid will leave deposits of foreign material. FLUID CHECKS

12. FLUID CHANGES • Most manufacturers recommend fluid changes every 100,000 miles (160,000 km) under normal driving conditions. • Some recommend a fluid change at 50,000 miles (80,000 km). • Severe driving conditions are described as: • Frequent trailer pulling. • Heavy city traffic, especially in areas where the temperature exceeds 90°F (32°C). • Very hilly or mountainous conditions. • Commercial use such as taxi or delivery service. • Police or ambulance usage.

13. FIGURE 11-7 In many transmissions, the fluid is expected to last 100,000 miles if the fluid temperature can be kept below 175°F (80°C); but the life will be cut in half for every 20°F increase in temperature. FLUID CHANGES

14. FLUID CHANGES • Fluid Changing, Dropping the Pan

15. FIGURE 11-8 Since most transmissions do not have drain plugs, the fluid must be spilled in a controlled fashion by lowering the pan at an angle. To do this, all but two bolts are removed. As the last two bolts are loosened, the pan will lower and fluid will spill over the edge. TECH TIP

16. FIGURE 11-9 Fluid is draining from this transmission pan. Note how the pan is hanging from two front bolts. FLUID CHANGES • To change transmission fluid, you should:

17. FIGURE 11-10 A gasket splitter is used to break the seal between the pan and transmission case. It is tapped in between the pan and case and then tapped sideways, around the pan. FLUID CHANGES

18. FIGURE 11-11 The filter is normally located in the oil pan (a); note the magnet inside the pan to trap ferrous metals. The filter is held by three screws (b). (Courtesy of Chrysler Corporation) FLUID CHANGES

19. FIGURE 11-12 This pan magnet has a thin coating of very fine iron particles and the pan is fairly clean. This is normal transmission wear. FLUID CHANGES

20. FIGURE 11-13 This depth filter has been cut open, and there are only a few small metal particles caught in the fold. TECH TIP • Some technicians will cut the old filter open so they can inspect for foreign particles

21. FIGURE 11-14 This “popcycle” was found laying in the transmission pan. It was used to plug the dipstick opening while the transmission was shipped to the vehicle assembly line. TECH TIP • Many transmissions are shipped to the vehicle assembly line wet (full of fluid) and a sealing device is used to close the openings for the drive shaft(s) and dipstick tube.

22. FIGURE 11-15 The flange area of a pan should be checked for distortion from overtightened bolts. These can be corrected by tapping down the raised areas as shown. TECH TIP • If the flange surface is bent or has dimples, it should be flattened using a hammer and block of wood, vise, or anvil.

23. FIGURE 11-16 If the transmission fluid and filter are replaced, the proper amount of fluid will overfill the transmission (a). The fill procedure should add fluid to a full level and then start the engine (b). Add additional fluid as needed to bring it to the proper level (c). Checking the engine with the engine off can show an overfill if the converter drains down (d). FLUID CHANGES

24. FIGURE 11-17 This fluid evacuation system has a small tube that can be inserted into the transmission dipstick tube. A connection to shop air is used to create a vacuum that sucks the fluid into the container. (Courtesy of ATEC Trans-Tool and Cleaning Systems) FLUID CHANGES • Fluid Changing, Fluid Evacuator • To change transmission fluid using an evacuating tool, you should: • Fluid Exchange and Flush Units • To change fluid using a transmission fluid exchange unit, you should:

25. FIGURE 11-18 This transmission flusher pumps new fluid into the transmission pump intake. It is operated until the old, dirty fluid is forced out. (Courtesy of Goodall Manufacturing) FLUID CHANGES

26. FIGURE 11-19 A fluid exchange unit is normally connected to the cooler return line, and it sends new fluid to the transmission to replace the old fluid being captured from the cooler. FLUID CHANGES

27. MANUAL LINKAGE CHECKS • The manual linkage is adjustable on most automatic transmissions. • This ensures the manual valve is positioned correctly relative to the gear selector. • Linkage position should be checked periodically because a misadjusted linkage can cause the manual valve to leak oil pressure into the wrong passage

28. FIGURE 11-20 Proper manual linkage ensures that manual valve position (a) matches correctly with the position of the manual shift lever and shift indicator (b). (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

29. FIGURE 11-21 As the shift selector is moved across the quadrant, you should be able to feel the detents inside the transmission. The detent feel should correspond with the gear position. (Reprinted with permission of General Motors) MANUAL LINKAGE CHECKS • To check manual linkage adjustment, you should:

30. FIGURE 11-22 This neutral safety switch is mounted in the transmission and operated by the manual lever cam. It always stays in proper adjustment. (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

31. FIGURE 11-23 This neutral safety switch is mounted to the outside of the transmission case. If the starter operates with the gear selector in a position other than park or neutral, the switch position should be adjusted. (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

32. MANUAL LINKAGE CHECKS • Manual Linkage Adjustment • The manual linkage should be adjusted if the starter engagements occur in the wrong position or the transmission detents do not align correctly relative to the gear range pointer. • To adjust manual shift linkage, you should: • Shift Lock Mechanism • The shift interlock mechanism locks the shifter in park position when the ignition key is removed.

33. FIGURE 11-24 A floor-mounted shift linkage using a cable (a); a floor-mounted shift linkage using rods (b); and a column-mounted shift linkage using rods (c). Each one has a method of adjusting the length for proper gear positioning (circled). (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

34. FIGURE 11-24 (CONTINUED) A floor-mounted shift linkage using a cable (a); a floor-mounted shift linkage using rods (b); and a column-mounted shift linkage using rods (c). Each one has a method of adjusting the length for proper gear positioning (circled). (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

35. FIGURE 11-25 This neutral safety switch is mounted to the outside of the transmission case. If the starter operates with the gear selector in a position other than park or neutral, the switch position should be adjusted. (Courtesy of Chrysler Corporation) MANUAL LINKAGE CHECKS

36. FIGURE 11-26 The manual shift lever is in park. The linkage adjustment is being tightened to lock the adjustment after making sure that the transmission is in park. MANUAL LINKAGE CHECKS

37. THROTTLE LINKAGE CHECKS • Nonelectronic transmissions may have a throttle rod or cable that connects the engine’s throttle linkage to the transmission’s throttle valve. • This linkage is commonly called a TV linkage. • The TV linkage controls a valve that produces a rise in TV or line pressure that is matched to the throttle position. • To check TV linkage, you should:

38. FIGURE 11-27 This TV cable connects the throttle body (a) to the transmission (b). The adjustment is at the throttle body cable bracket. (Courtesy of Chrysler Corporation) THROTTLE LINKAGE CHECKS

39. FIGURE 11-28 This throttle linkage is adjusted by turning the two adjusting nuts until the cable stopper ring is the correct distance from the housing end. THROTTLE LINKAGE CHECKS • Throttle Linkage Adjustments • Like the manual shift linkage, TV linkage is adjustable. • Always consult the service manual for that particular vehicle when making an adjustment. • To adjust TV linkage, you should: • Throttle Position Sensor Position Adjustment

40. FIGURE 11-29 This throttle cable uses a “snap lock” adjuster that is adjusted using the procedure shown. (Reprinted with permission of General Motors) THROTTLE LINKAGE CHECKS

41. FIGURE 11-30 This “self-adjusting” TV cable is adjusted using the procedure shown. (Reprinted with permission of General Motors) THROTTLE LINKAGE CHECKS

42. FIGURE 11-31 This “self-adjusting” TV cable used with some transaxles is adjusted using the procedure shown. (Reprinted with permission of General Motors) THROTTLE LINKAGE CHECKS

43. FIGURE 11-32 The throttle position sensor normally has an adjustment so it is positioned correctly on the throttle body. (Courtesy of Chrysler Corporation) THROTTLE LINKAGE CHECKS

44. BAND ADJUSTMENTS • At one time, a common transmission maintenance procedure was to readjust the band clearance. • Wear of the friction material would increase the clearance to the point where engagement would not be complete and slippage would occur. • To readjust a band, you should:

45. FIGURE 11-33 When a band is new, the servo piston travels only a short distance to apply it. As the lining wears, servo piston travel increases; if there is too much wear, the band might not tighten completely. BAND ADJUSTMENTS

46. FIGURE 11-34 This band is adjusted by holding the adjuster screw while the lock nut is loosened (a). Step 2 turns the adjuster screw inward to 72 in-lbs (8 N-m) of torque. The special adapter is used if there is tight access (b). Step 3 is to back off the adjusting screw the proper number of turns and tighten the lock nut to the correct torque. (Courtesy of Chrysler Corporation) BAND ADJUSTMENTS

47. SUMMARY • Automatic transmissions require periodic service and maintenance. • Transmission fluid should be regularly checked for correct level and good condition. • The transmission fluid should be changed at the required intervals or if the condition indicates the need for a change. • The manual shift linkage and the throttle linkage need to be checked and adjusted if necessary. • Some transmissions have one or more bands that may need to be adjusted.

48. REVIEW QUESTIONS • Servicing and maintaining an automatic transmission includes: • Checking the _________ level. • Changing the _________. • Cleaning or replacing the _________. • Checking and adjusting the _________ and _________ linkages. • _________ the bands if required. • It usually takes _________ _________ to change the fluid level from low to full on the dipstick. • Mushy operation, lack of engagement, or slipping can be caused by a transmission that has a fluid level that is too _________.

49. REVIEW QUESTIONS 4. Before checking the fluid level, the vehicle should • be on _________ ground. • be in _________. • be at normal operating _________. • have the engine _________. • All transaxles share fluid between the differential and the transmission. True or False? • When checking the fluid level, the _________ and _________ should also be checked. • The normal color of automatic transmission fluid is _________. • What is indicated by these fluid conditions? • Dark brown color • Burned odor • Pink or milky color • Gold or brown coating on the dipstick • Metallic appearance • Foamy

50. REVIEW QUESTIONS • An automatic transmission can be ruined by contaminated _________. • Severe driving conditions include: • Frequent _________ pulling. • Heavy _________ and _________ traffic. • _________ weather conditions. • _________ service. • _________ or _________ police usage. • The major factor that affects transmission fluid life is _________. • To change fluid in most automatic transmissions, the _________ must be removed. • Before installing the clean pan after draining the fluid, check the pan for _________ and _________ sealing surface. • The notchy feel and clicking sound when a gear is selected is caused by the spring-loaded _________.