For 1990-2009 cars

## Transmission Fluid Check Preliminary Check

The condition of an automatic transmission not operating properly may be influenced by one, or a combination of the following items:

• | High or low oil level

• | Engine performance. Refer to Engine Mechanical or Engine Controls.

• | TV cable adjustment

• | Manual linkage adjustment

• | Internal oil leaks. Refer to Automatic Transmission or Transmission/Transfer Case Unit Repair Manual.

• | Electrical System. Refer to Engine Controls or Electrical Diagnosis.

• | Transmission or other mechanical component. Refer to Automatic Transmission or Transfer Case Unit Repair Manual.

• | Temperature

## Transmission Fluid Check Oil Level Check

### Inspection Procedure

Use the fluid level screw (5) for diagnosing a transmission fluid leak or for resetting the transmission fluid level after the service that involves a loss of fluid.

For inspecting the oil color, level and condition, refer to Transmission Fluid Check .

Caution: Removal of the fluid level screw when the transaxle fluid is hot may cause injury. Use care to avoid contact of transaxle fluid to exhaust pipe.

1. Inspect the fluid level when the transmission is near room temperature or at 40°C (104°F).
2. Be sure the engine is running.
3. Raise the vehicle on a hoist. Refer to General Information.
4. Place the oil container under the check plug.
5. Remove the oil check plug.
6. Ensure that the oil level is at the bottom of the oil check hole. Because the transmission operates correctly over a range of fluid levels, the fluid may or may not drain out of the screw hole after removing the screw.

#### Adding Transmission Oil

If the fluid drains through the screw hole the transmission may have been overfilled. When the fluid stops draining the fluid level is correct, and you may install the check plug. If the fluid does not drain through the screw hole, the transmission fluid level may have been low. Add fluid at the vent cap (2) location in half liter (1 pint) increments until the oil level is at the bottom of the oil check hole.

1. Install the oil check plug.

Tighten
Tighten the oil check plug to 14 N·m (124 lb in).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Lower the vehicle.

## Transmission Fluid Check Color, Level, Condition

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Important: See 4T40 Oil Level Checking and Fill Procedure. The fluid should be level with the check plug in the trans case while running at 41°C (105°F). Important: The fluid level to be in cross-hatched area on fluid level indicator blade. Check at operating temperature (3T40).

Check the fluid color.

Is the fluid color red?

--

Go to Step 4

Go to Step 2

2 | Check the fluid color. Is the fluid color a non-transparent pink? | -- | Go to Step 20 | Go to Step 3
3 | Check the fluid color. Important: Transmission fluid may turn dark with normal use and does not always indicate contamination or oxidation. Is the fluid color light brown? | -- | Go to Step 18 | --
4 | Check the fluid level. Is the fluid level high? | -- | Go to Step 8 | Go to Step 5
5 | Check the fluid level. Is the fluid level OK? | -- | Go to Step 21 | Go to Step 6
6 | Check the fluid level. Is the fluid level low? | -- | Go to Step 9 | Go to Step 7
7 | Check the fluid level. Does the fluid have foam? | -- | Go to Step 12 | Go to Step 13
8 | Remove excess fluid. Did you remove the excess fluid? | -- | Go to Step 21 | --
9 | Add fluid in order to obtain the proper level. Did you add fluid to the proper level? | -- | Go to Step 10 | --
10 | Inspect for external leaks. Refer to Fluid Leak Diagnosis. Are there any external leaks? | -- | Go to Step 11 | --
11 | Repair the leak. Did you repair the leak? | -- | Go to Step 21 | --
12 | Inspect for a high fluid level. Is the fluid level high? | -- | Go to Step 8 | Go to Step 13
13 | Check for contaminants in the fluid. Are there contaminants in the fluid? | -- | Go to Step 14 | --
14 | Drain the fluid in order to determine the source of contamination. Did you drain the fluid? | -- | Go to Step 15 | --
15 | Perform a transmission overhaul. Refer to Unit Repair. Did you perform the procedure? | -- | Go to Step 16 | --
16 | Add new fluid. Did you add new fluid? | -- | Go to Step 17 | --
17 | Check the fluid level. Did you check the fluid level? | -- | Go to Step 21 | --
18 | Drain the fluid in order to determine if there is contamination. Are there large pieces of metal or other material in the bottom of the pan. | -- | Go to Step 15 | Go to Step 19
19 | Change the fluid and filter. Did you change the fluid and filter? | -- | Go to Step 21 | --
20 | Replace the cooler. Did you replace the cooler? | -- | Go to Step 15 | --
21 | Perform the road test. Refer to Transmission Diagnosis. Did you Perform the test? | -- | System OK | --

## Transmission Fluid Check Diagnosis

#### Transmission Fluid Checking Procedure (1998 4T40-E)

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
2. Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
3. Raise the vehicle on a hoist. The vehicle must be level, with the engine running and the shift lever in the PARK range. Refer to Vehicle Lifting and Jacking in General Information.

Caution: The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.

4. Remove the transmission plug.

Important: The transmission fluid may darken with normal use and does not always indicate contamination or oxidation.

5. Check the fluid color. If necessary, use a small screwdriver as a dipstick.

Is the fluid color clear red or light brown with no burnt odor?

At least 40°C

(At least 104°F)

Go to Step 4

Go to Step 2

2 | Does the fluid have a burnt odor or a dark brown color? | -- | Go to Step 8 | Go to Step 3
3 | Does the fluid have a cloudy or milky appearance? | -- | Go to Step 7 | Go to Step 8
4 | Check the fluid level. The fluid level should be even with the bottom of the threaded plug hole. Is the fluid level low? | -- | Go to Step 5 | Go to Step 11
5 | Add DEXRON® III automatic transmission fluid in increments of 0.5L until the fluid drains from the plug hole. Did you add more than 1.5L to the transmission? | -- | Go to Step 6 | Go to Step 11
6 | The transmission may have a leak. Refer to Fluid Leak Diagnosis and Repair . Was a transmission fluid leak found? | -- | Go to Step 9 | Go to Step 11
7 | The transmission fluid is contaminated with engine coolant. Repair or replace the transmission cooler in the radiator. Is the transmission cooler repair complete? | -- | Go to Step 10 | --
8 |

1. Drain the fluid by removing the bottom pan.

Important: A very small amount of material in the bottom of the bottom pan is a normal condition.

2. Check the bottom pan for any excessive debris.

Was excessive debris found?

--

Go to Step 9

Go to Step 10

9 |

1. Repair the transmission if required (in some cases, overhaul may be required).
2. Flush the transmission oil cooler and pipes and check flow. Refer to Transmission Fluid Cooler Flushing and Flow Test .
3. Add enough DEXRON® III automatic transmission fluid to bring the fluid level to the bottom of the threaded plug hole.
4. Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
5. Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
6. Raise the vehicle on a hoist. The vehicle must be level, with the engine running and the shift lever in the PARK range. Refer to Vehicle Lifting and Jacking in General Information.

Caution: The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.

7. Remove the transmission plug.
8. If needed, add DEXRON® III automatic transmission fluid in increments of 0.5L until the fluid drains from the threaded plug hole.
9. Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice .
10. Wipe any excess fluid from the transmission with a rag or shop towel.

Is the repair complete?

At least 40°C

(At least 104°F)

12 N·m

(9 lb ft)

Refer to Functional Test

--

10 |

1. Change the fluid and the fluid filter. Refer to Transmission Filter Replacement.
2. Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
3. Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
4. Raise the vehicle on a hoist. The vehicle must be level with the engine running and the shift lever in the PARK range. Refer to Vehicle Lifting and Jacking in General Information.

Caution: The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.

5. Remove the transmission plug.
6. If needed, add DEXRON® III automatic transmission fluid in increments of 0.5L until the fluid drains from the threaded plug hole.
7. Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice .
8. Wipe any excess fluid from the transmission with a rag or shop towel.

Is the repair complete?

At least 40°C

(At least 104°F)

12 N·m

(9 lb ft)

Refer to Functional Test

--

11 |

1. Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice .
2. Wipe any excess fluid from the transmission with a rag or shop towel.

Is the repair complete?

12 N·m

(9 lb ft)

Refer to Functional Test

--