18NA355

Service Bulletin
Bulletin No.:
18-NA-355
Date:
April, 2020
TECHNICAL
Subject:
Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40
and 128 KM/H) at Steady Speed
Attention: This Bulletin only applies to vehicles sold in the U.S., Canada and Middle East
Operations (MEO). Mexico and Export Regions should follow Bulletin 19-NA-018.
Note: This procedure should only be completed once
per vehicle. Any vehicle that returns with suspect
shudder should be diagnosed utilizing published
diagnostics, GDS, PICO Scope or other diagnostic
tools. Sometimes shudder is not caused by the torque
converter clutch (TCC). In some instances, shudder is
fish bite, chuggle, surge or vibration.
Model Year:
Brand:
Model:
ATS
CTS
Cadillac
CT6
from
to
2016
2019
2016
2018
from
to
Engine:
(2.0L, 2.5L, 3.0L,
3.6L, 5.3L, 6.2L)
Transmission:
(8L45, 8L90
Automatic)
Feb.
1, 2019
LCV, LGX, LTG,
LT4, LF4
M5N, M5T, M5U
LGX, LGW, LTG
M5N, M5X
L86
M5U
EOP
Escalade
Models
2015
2017
Camaro
2016
2019
Feb.
1, 2019
LGX, LTG, LT1
M5T, M5U
Colorado
2017
2019
March
1, 2019
LGZ
M5T
Chevrolet
GMC
Date Breakpoint:
SOP
Corvette
2015
2019
Feb.
1, 2019
LT1, LT4
M5U
Silverado
Models
2015
2018
EOP
L83, L86, L8B
M5U, M5X
Canyon
2017
2019
March
1, 2019
LGZ
M5T
Sierra
Models
2015
2018
L83, L86, L8B
M5U, M5X
Yukon
Models
2015
L86
M5U
EOP
2017
Involved Region or Country
United States, Canada, Middle East Operations (MEO)
Condition
Some customers may comment that their vehicle is experiencing a shake and/or shudder
during light throttle acceleration between 25 and 80 mph (40 and 128 km/h) steady state
driving when transmission is not actively shifting gears.
⇒ The condition may be described as if they are driving over rumble strips or a
concrete road surface with rough expansion joints.
Cause
Copyright 2020 General Motors LLC. All Rights Reserved.
This condition may be due to Torque Converter Clutch (TCC) Shudder.
Page 2
April, 2020
Bulletin No.: 18-NA-355
Note: This procedure should only be completed once per vehicle. Any vehicle that
returns with suspect shudder should be diagnosed utilizing published diagnostics, GDS,
PICO Scope or other diagnostic tools. Sometimes shudder is not caused by the torque
converter clutch (TCC). In some instances, shudder is fish bite, chuggle, surge or
vibration.
Correction
Vehicles that are presented with TCC shudder should have the appropriate fluid
exchange procedure completed. Diagnosis beyond the customer compliant is not
required if vehicle was built prior to production dates indicated above.
For vehicles built after the production dates listed above.
⇒
If a customer presents a vehicle with a similar complaint, follow normal SI
diagnostics. These vehicles are already equipped with the latest HP fluid.
Special Tools
DT-52263 Transmission Fluid Exchange Kit:
• DT-52263-1 Block Assembly (includes fluid drain
hose, spring clamp)
• DT-52263-2 Cooler Line Plug (qty 3) (use with rear
differential cooler and Camaro V8 non rear
differential cooler)
• DT-52263-3 ½” Cooler Line Flush Adapter for
2019 Silverado and Sierra
• DT-52263-4 3/8” Hose Adapter (6” long with 2
hose clamps)
• DT-52263-5 Radiator Cooler Drain Adapter
3763203
•
DT-51190 Transmission Oil Fill Adapter
5181938
•
GE-47716-2 Graduated Bucket
1215917
•
DT-45096 TransFlow Cooler Flush Machine
Bulletin No.: 18-NA-355
April, 2020
4733125
•
DT-45096-31 TransFlow Adapter (one of two
pieces from DT-45096-30)
Page 3
3. Connect power leads to the vehicle 12-volt DC
supply.
4. Turn the TransFlow main switch ON.
5. Connect air supply to the DT-45096.
6. Place the TransFlow supply hose with adapter
DT-45096-31 into a waste reservoir using care not
to spill the expelled fluid.
7. Switch the DT-45096 TransFlow to Flow and allow
all the fluid in the supply reservoir to be removed
and placed in the waste reservoir.
8. Switch the control switch back to idle.
Fluid Exchange Procedure - Colorado, Canyon,
Silverado, Sierra, Yukon Denali and Escalade
Models with an Accessible Transmission Oil
Cooler Line Block Assembly
Service Procedure
Initial TransFlow Flush Machine Setup
Important: The prepping procedure only needs to be
completed if the DT-45096 supply reservoir has
DEXRON VI fluid in it and has not been converted to
use the new blue label Mobil 1 Synthetic LV ATF HP
fluid.
Note: The prepping procedure only needs to be
completed if HP fluid is not in the supply reservoir.
1. Connect the TransFlow adapter DT-45096-31 to
the supply line of the DT-45096 TransFlow
machine.
Important: This procedure must be followed as
published. The exchange process is required to obtain
proper level of new blue label Mobil 1 Synthetic LV ATF
HP fluid. Intermixing of other types of transmission fluid
or aftermarket additive packages will result in a low
concentration level of new fluid and will not provide
satisfactory results.
1. Fill the DT-45096 with 20 quarts of HP fluid.
2. Raise the vehicle on a hoist.
5182541
3. Install the DT-45096-31 TransFlow adapter (1) to
the DT-51190 fluid fill adapter (2).
5180884
2. Switch the DT-45096 TransFlow to Idle.
Page 4
April, 2020
Bulletin No.: 18-NA-355
3723844
8. Remove the level set plug (1) from the
transmission.
Important: DO NOT over tighten the DT-51190 as it
can be damaged by excessive torque. DO NOT exceed
9 Y (80 lb in).
9. Install the DT-51190/DT-45096-31 assembly and
hand tighten as shown in the graphic above.
5180563
4. Remove the transmission oil cooler pipe assembly
from the transmission.
5. Install the DT-52263-1 Adapter Block Assembly
(1), reusing the seal from the transmission oil
cooler pipe assembly.
6. Tighten the bolt (2) to 22 Y (16 lb ft).
7. Place the hose (3) in the GE-47716-2 Graduated
Measuring Bucket, utilizing a Spring Clamp to
retain the hose.
3723839
Bulletin No.: 18-NA-355
April, 2020
10. Connect the TransFlow fluid feed (supply) line (3)
to the DT-45096-31 adapter (2).
11. Lower the vehicle.
Caution: DO NOT REMOVE MORE THAN 3
QUARTS OF FLUID AS IT COULD CAUSE FLUID
PUMP CAVITATION AND POSSIBLY DAMAGE THE
TRANSMISSION.
12. Utilizing the graduated bucket, start the engine and
run 30- 45 seconds until 3 quarts of fluid is
expelled.
13. Shut the engine off immediately.
14. Connect the DT-45096 to the vehicle battery 12
volts and connect shop air to the air connection.
Page 5
17. Switch the TransFlow DT-45096 to Flow and start
the engine:
17.1. Add a maximum of 4 quarts of HP Fluid to
the transmission, turn the TransFlow switch
to idle once 4 quarts have been added, while
allowing 4 additional quarts of oil to fill the
DT-graduated bucket (Reducing fluid level in
the TransFlow from 16 – 12).
Note: DO NOT add additional transmission fluid until
the 4 quarts of oil have been removed from the
transmission (Reducing fluid level in the TransFlow
from 12–8).
17.2. Repeat step 17.1.
17.3. Add a maximum of 5 quarts of HP fluid to the
transmission while allowing 5 additional
quarts of oil to fill the DT-graduated bucket
(Reducing fluid level in the TransFlow from 8
– 3).
5181027
15. Switch the DT-45096 TransFlow to Flow and add 4
quarts of HP to the transmission.
5181401
18.
19.
5181020
16. Switch the DT-45096 TransFlow to Idle (Reducing
fluid level in the TransFlow from 20–16).
20.
21.
17.4. Shut the engine off once 16 quarts of fluid
have been collected.
17.5. Properly dispose of the expelled
transmission fluid.
Raise the vehicle.
Disconnect the DT-45096 TransFlow feed (supply)
line from DT-45096-31 TransFlow adapter.
Using care, remove DT-45096-31/DT-51190 as an
assembly.
Remove the DT-51190 fluid fill adapter from
DT-45096-31 hose.
Page 6
April, 2020
22. Install the level set plug.
Tighten
Tighten the plug to 9 Y (80 lb in).
23. Remove DT-52263-1 Adapter Block Assembly
from the transmission.
24. If equipped, remove the Thermal By-Pass Block
from the cooler pipes on the Escalade, Silverado,
Sierra and Yukon Models.
Bulletin No.: 18-NA-355
28. Flush the vehicle cooler and lines using 2 quarts of
HP fluid.
⇒ Flush 1 quart of fluid through the lines, then
switch the hose connections and flush 1 quart
of fluid in the opposite direction.
29. Remove the DT-51190/DT-45096-31 assembly.
30. If equipped, install the Thermal By-Pass Block from
the cooler pipes on the Escalade, Silverado, Sierra
and Yukon Models.
31. Install the transmission oil cooler pipe using a new
cooler block seal.
32. Partially lower the vehicle.
33. Start the engine.
34. Using care, shift the transmission through all
forward ranges and Reverse.
35. Shift the transmission into Park.
36. Perform the Transmission Fluid Level and
Condition Check outlined below in this procedure:
36.1. Get the transmission fluid temperature to the
proper temperature.
36.2. Install the level set plug.
Tighten
1762577
25. Install DT-45096-31 adapters (1) to the
transmission oil cooler lines.
26. Connect the DT-45096 TransFlow to the
DT-45096-31 adapters.
Tighten the plug to 9 Y (80 lb in).
The TCC shudder condition should be directional
improved immediately after the fluid exchange
procedure. It may take up to 320 km (200 mi) for the
TCC shudder condition to be eliminated. It is not a
requirement for the dealer to drive the vehicle 320 km
(200 mi). The customer should be advised that the full
effect will take up to 320 km (200 mi) and a minimum of
two cold to operating temperature drive cycles.
Fluid Exchange Procedure - Camaro (Except
Camaro V8-See Procedure below for Camaro
V8), CTS and ATS Not Equipped with a Rear
Differential Cooler
Important: This procedure must be followed as
published. The exchange process is required to obtain
proper level of new blue label Mobil 1 Synthetic LV ATF
HP fluid. Intermixing of other types of transmission fluid
or aftermarket additive packages will result in a low
concentration level of new fluid and will not provide
satisfactory results.
1. Fill the DT-45096 with 20 quarts of HP fluid.
5210461
27. Switch the DT-45096 TransFlow to Flush.
Bulletin No.: 18-NA-355
April, 2020
Page 7
4194576
Note: The MAF sensor must stay connected so that no
DTCs will set.
2. Separate the engine upper air filter box (1) from the
lower air filter housing to gain access to the upper
transmission oil cooler line.
5181322
5181307
Note: Upper air filter box removed for clarity.
3. Remove the cooler line from the transmission oil
cooler.
4. Install end of the DT-52263-5 Radiator Cooler
Drain Adapter (1) to the DT-52263-1 Block
Assembly.
5. Install the DT-52263-5 Radiator Cooler Drain
Adapter into the upper transmission oil cooler line
port of the transmission oil cooler.
6. Install the DT-45096-31 adapter (3) over the
removed transmission oil cooler line (2) to prevent
any fluid spillage.
Page 8
April, 2020
Bulletin No.: 18-NA-355
7. Place the hose in the GE-47716-2 Graduated
Measuring Bucket, utilizing a Spring Clamp to
retain the hose.
8. Raise the vehicle.
5182541
9. Install the DT-45096-31 adapter (1) to the
DT-51190 fluid fill adapter (2).
3723839
Important: DO NOT overtighten the DT-51190 as it
can be damaged by excessive torque. Do not
exceed 9 Y (80 lb in).
11. Install the DT-51190/DT-45096-31 assembly and
hand tighten.
12. Connect the TransFlow fluid feed (supply) line (3)
to the DT-45096-31 adapter (2).
13. Lower the vehicle.
Caution: DO NOT REMOVE MORE THAN 3 QTS OF
FLUID AS IT COULD CAUSE FLUID PUMP
CAVITATION AND POSSIBLY DAMAGE THE
TRANSMISSION.
14. Utilizing the graduated bucket, start the engine
and run 30-45 seconds until 3 quarts of fluid is
expelled.
15. Shut the engine off immediately.
16. Connect the DT-45096 to the vehicle battery 12
volts and connect shop air to the air connection.
3723844
10. Remove the level set plug (1) from the
transmission oil pan.
5181027
Bulletin No.: 18-NA-355
April, 2020
Page 9
Important: ADDING TOO MUCH FLUID TO THE
TRANSMISSION MAY CAUSE FLUID TO BE
EXPELLED FROM THE VENT SYSTEM. DO NOT
OVERFILL THE TRANSMISSION.
17. Switch the DT-45096 TransFlow to Flow and add 4
quarts of HP to the transmission.
5181020
18. Set the TransFlow switch to idle (Reducing fluid
level in the TransFlow from 20–16).
19. Switch the TransFlow DT-45096 to Flow and start
the engine:
19.1. Add a maximum of 4 quarts of HP Fluid to
the transmission, turn the TransFlow switch
to idle once 4 quarts have been added, while
allowing 4 additional quarts of oil to fill the
DT-graduated cylinder (Reducing fluid level
in the TransFlow from 16–12).
Note: DO NOT add additional transmission fluid until
the 4 quarts of oil have been removed from the
transmission (Reducing fluid level in the TransFlow
from 12–8).
19.2. Repeat step 19.1.
19.3. Add a maximum of 5 quarts of HP Fluid to
the transmission while allowing 5 additional
quarts of oil to fill the DT-graduated bucket
(Reducing fluid level in the TransFlow from
8–3).
5181401
20.
21.
22.
23.
24.
25.
26.
27.
19.4. Shut the engine off once 16 quarts of oil
have been collected.
19.5. Properly dispose of the collected
transmission fluid.
Remove the DT-52263-5 Radiator Cooler Drain
Adapter and DT-52263-1 Block Adapter from the
transmission oil cooler.
Remove the DT-45096-31 from the transmission oil
cooler line and install the transmission oil cooler
line using a new retaining clip.
Install the engine upper air filter box back into
position.
Partially raise the vehicle.
Start the engine.
Using care, shift the transmission through all
forward ranges and Reverse.
Shift the transmission into Park.
Perform the Transmission Fluid Level and
Condition Check outlined below in this procedure:
27.1. Get the transmission fluid temperature to the
proper temperature.
27.2. Raise the vehicle and remove the DT-51190/
DT-45096-31 assembly.
27.3. Install the level set plug.
Tighten
Tighten the plug to 9 Y (80 lb in).
Page 10
April, 2020
Bulletin No.: 18-NA-355
The TCC shudder condition should be directional
improved immediately after the fluid exchange
procedure. It may take up to 320 km (200 mi) for the
TCC shudder condition to be eliminated. It is not a
requirement for the dealer to drive the vehicle 320 km
(200 mi). The customer should be advised that the full
effect will take up to 320 km (200 mi) and a minimum of
two cold to operating temperature drive cycles.
Fluid Exchange Procedure – Camaro V8 Not
Equipped with a Rear Differential Cooler
Important: This procedure must be followed as
published. The exchange process is required to obtain
proper level of new blue label Mobil 1 Synthetic LV ATF
HP fluid. Intermixing of other types of transmission fluid
or aftermarket additive packages will result in a low
concentration level of new fluid and will not provide
satisfactory results.
1. Fill the DT-45096 with 20 quarts of HP fluid.
4194576
Note: The MAF sensor must stay connected so that no
DTCs will set.
2. Separate the engine upper air filter box (1) from the
lower air filter housing to gain access to the upper
transmission oil cooler line.
Bulletin No.: 18-NA-355
April, 2020
Page 11
5181307
3723844
Note: Upper air filter box removed for clarity.
3. Remove the upper cooler line from the
transmission oil cooler.
4. Install the DT-52263-2 Cooler Line Plug into the
radiator cooler.
5. Install the DT-52263-4 Hose onto DT-52263-1
Block Assembly install the DT-52263-4 onto the
removed transmission oil cooler line.
6. Place the hose of the DT-52263-1 in the
GE-47716-2 Graduated Measuring Bucket,
utilizing a Spring Clamp to retain the hose.
7. Raise the vehicle.
9. Remove the level set plug (1) from the
transmission oil pan.
3723839
5182541
8. Install the DT-45096-31 adapter (1) to the
DT-51190 fluid fill adapter (2).
Important: DO NOT overtighten the DT-51190 as it
can be damaged by excessive torque. Do not
exceed 9 Y (80 lb in).
10. Install the DT-51190/DT-45096-31 assembly and
hand tighten.
11. Connect the TransFlow fluid feed (supply) line (3)
to the DT-45096-31 adapter (2).
12. Lower the vehicle.
Caution: DO NOT REMOVE MORE THAN 3 QTS OF
FLUID AS IT COULD CAUSE FLUID PUMP
CAVITATION AND POSSIBLY DAMAGE THE
TRANSMISSION.
13. Utilizing the graduated bucket, start the engine and
run 30-45 seconds until 3 quarts of fluid is
expelled.
Page 12
April, 2020
14. Shut the engine off immediately.
15. Connect the DT-45096 to the vehicle battery 12
volts and connect shop air to the air connection.
Bulletin No.: 18-NA-355
18. Switch the TransFlow DT-45096 to Flow and start
the engine:
18.1. Add a maximum of 4 quarts of HP Fluid to
the transmission, turn the TransFlow switch
to idle once 4 quarts have been added, while
allowing 4 additional quarts of oil to fill the
DT-graduated cylinder (Reducing fluid level
in the TransFlow from 16–12).
Note: DO NOT add additional transmission fluid until
the 4 quarts of oil have been removed from the
transmission (Reducing fluid level in the TransFlow
from 12–8).
18.2. Repeat step 18.1.
18.3. Add a maximum of 5 quarts of HP Fluid to
the transmission while allowing 5 additional
quarts of oil to fill the DT-graduated bucket
(Reducing fluid level in the TransFlow from
8–3).
5181027
Important: ADDING TOO MUCH FLUID TO THE
TRANSMISSION MAY CAUSE FLUID TO BE
EXPELLED FROM THE VENT SYSTEM. DO NOT
OVERFILL THE TRANSMISSION.
16. Switch the DT-45096 TransFlow to Flow and add 4
quarts of HP to the transmission.
5181401
5181020
17. Set the TransFlow switch to idle (Reducing fluid
level in the TransFlow from 20–16).
18.4. Shut the engine off once 16 quarts of oil
have been collected.
18.5. Properly dispose of the collected
transmission fluid.
19. Remove the DT-52263-4 and DT-52263-1 Block
Adapter from the transmission oil cooler line.
20. Remove the DT-52263-2 Cooler Line Plug from the
transmission oil cooler at the radiator and install
the transmission oil cooler line using a new
retaining clip.
Bulletin No.: 18-NA-355
April, 2020
Page 13
21. Install the engine upper air filter box back into
position.
22. Partially raise the vehicle.
23. Start the engine.
24. Using care, shift the transmission through all
forward ranges and Reverse.
25. Shift the transmission into Park.
26. Perform the Transmission Fluid Level and
Condition Check outlined below in this procedure:
26.1. Get the transmission fluid temperature to the
proper temperature.
26.2. Raise the vehicle and remove the DT-51190/
DT-45096-31 assembly.
26.3. Install the level set plug.
Tighten
Tighten the plug to 9 Y (80 lb in).
The TCC shudder condition should be directional
improved immediately after the fluid exchange
procedure. It may take up to 320 km (200 mi) for the
TCC shudder condition to be eliminated. It is not a
requirement for the dealer to drive the vehicle 320 km
(200 mi). The customer should be advised that the full
effect will take up to 320 km (200 mi) and a minimum of
two cold to operating temperature drive cycles.
Fluid Exchange Procedure - Camaro, CTS and
ATS Equipped with a Rear Differential Cooler
Important: This procedure must be followed as
published. The exchange process is required to obtain
proper level of new blue label Mobil 1 Synthetic LV ATF
HP fluid. Intermixing of other types of transmission fluid
or aftermarket additive packages will result in a low
concentration level of new fluid and will not provide
satisfactory results.
1. Fill the DT-45096 with 20 quarts of HP fluid.
2. Raise the vehicle on a hoist.
5182245
3. Remove the lower/front transmission oil cooler line
(2) at the rear differential.
4. Install the DT-52263-2 Cooler Line Plug (1) into the
rear differential to prevent fluid loss.
5. Install one end of the DT-52263-4 hose (4) to the
open port of the DT-52263-1 Block Assembly (3).
6. Install the other end of the DT-52263-4 hose to the
transmission oil cooler line.
7. Place the hose in the GE-47716-2 Graduated
Measuring Bucket, utilizing a Spring Clamp to
retain the hose.
5182541
8. Install the DT-45096-31 adapter (1) to the
DT-51190 fluid fill adapter (2).
Page 14
April, 2020
Bulletin No.: 18-NA-355
12. Lower the vehicle.
Caution: DO NOT REMOVE MORE THAN 3 QTS OF
FLUID AS IT COULD CAUSE FLUID PUMP
CAVITATION AND POSSIBLY DAMAGE THE
TRANSMISSION.
13. Utilizing the graduated bucket, start the engine and
run 30-45 seconds until 3 quarts of fluid is
expelled.
14. Shut the engine off immediately.
15. Connect the DT-45096 to the vehicle battery 12
volts and connect shop air to the air connection.
3723844
9. Remove the level set plug (1) from the
transmission oil pan.
5181027
3723839
Important: DO NOT over tighten the DT-51190 as it
can be damaged by excessive torque. Do not
exceed 9 Y (80 lb in).
10. Install the DT-51190/DT-45096-31 assembly and
hand tighten.
11. Connect the TransFlow fluid feed (supply) line (3)
to the DT-45096-31 adapter (2).
16. Switch the TransFlow DT-45096 to Flow and add 4
quarts of HP to the transmission.
17. Set the TransFlow switch to idle (Reducing fluid
level in the TransFlow from 20–16).
18. Switch the TransFlow DT-45096 to Flow and start
the engine:
18.1. Add a maximum of 4 quarts of HP Fluid to
the transmission, turn the TransFlow switch
to idle once 4 quarts have been added, while
allowing 4 additional quarts of oil to fill the
DT-graduated bucket (Reducing fluid level in
the TransFlow from 16–12).
Note: DO NOT add additional transmission fluid until
the 4 quarts of oil have been removed from the
transmission (Reducing fluid level in the TransFlow
from 12–8).
18.2. Repeat step 18.1.
18.3. Add a maximum of 5 quarts of HP Fluid to
the transmission while allowing 5 additional
quarts of oil to fill the DT-graduated bucket
(Reducing fluid level in the TransFlow from
8–3).
Bulletin No.: 18-NA-355
April, 2020
Page 15
(200 mi). The customer should be advised that the full
effect will take up to 320 km (200 mi) and a minimum of
two cold to operating temperature drive cycles.
Fluid Exchange Procedure - Corvette and CT6
Important: The Drain and Fill Procedure Will Need
to be Performed Three Times.
Important: This procedure must be followed as
published. The exchange process is required to obtain
proper level of new blue label Mobil 1 Synthetic LV ATF
HP fluid. Intermixing of other types of transmission fluid
or aftermarket additive packages will result in a low
concentration level of new fluid and will not provide
satisfactory results.
1. Fill the DT-45096 with 24 quarts of HP fluid.
2. Raise the vehicle.
3. Using care, remove the transmission oil pan and
drain the transmission fluid.
4. Install the transmission oil pan.
5181401
19.
20.
21.
22.
23.
24.
18.4. Shut the engine off once 16 quarts of fluid
have been collected.
18.5. Properly dispose of the collected
transmission fluid.
Raise the vehicle.
Remove the DT-52263-2 Cooler Line Plug from
rear differential and install the transmission oil
cooler line using a new retainer clip.
Remove the DT-52263-4 from the transmission oil
cooler line.
Install the transmission oil cooler line using a new
retainer clip.
Partially lower the vehicle.
Using care, shift the transmission through all
forward ranges and Reverse.
24.1. Get the transmission fluid temperature to the
proper temperature.
24.2. Raise the vehicle and remove the DT-51190/
DT-45096-31 assembly.
24.3. Install the level set plug.
5182541
5. Install the DT-45096-31 adapter (1) to the
DT-51190 fluid fill adapter (2).
Tighten
Tighten the plug to 9 Y (80 lb in).
The TCC shudder condition should be directional
improved immediately after the fluid exchange
procedure. It may take up to 320 km (200 mi) for the
TCC shudder condition to be eliminated. It is not a
requirement for the dealer to drive the vehicle 320 km
3723844
Page 16
April, 2020
Bulletin No.: 18-NA-355
Transmission Fluid Level and Condition
Check
6. Remove the level set plug (1) from the
transmission oil pan.
This procedure checks both the transmission fluid level,
as well as the condition of the fluid itself. Because the
transmission on this vehicle is not equipped with a fill
tube and dipstick, a tube in the bottom pan is used to
set the fluid level.
Warning: The transmission fluid level must be
checked when the transmission fluid temperature
(TFT) is between 35–45°C (95–113°F). If the TFT is
not within this range, either idle or brake torque the
vehicle to raise the fluid temperature, or shut off the
vehicle to allow the fluid to cool as required. Setting
the fluid level with a TFT outside this range will
result in either an under or over-filled transmission.
TFT>45°C=under-filled, TFT<35°C=over-filled. An
under-filled transmission will cause premature
component wear or damage. An over-filled
transmission will cause fluid to discharge out the
vent tube, possibly causing a fire that may result in
serious bodily injury or severe vehicle damage,
fluid foaming, or pump cavitation.
3723839
Important: DO NOT over tighten the DT-51190 as it
can be damaged by excessive torque. Do not
exceed 9 Y (80 lb in).
7. Install the DT-51190/DT-45096-31 assembly and
hand tighten.
8. Connect the TransFlow fluid feed (supply) line (3)
to the DT-45096-31 adapter (2).
9. Connect the DT-45096 TransFlow to the vehicle
battery 12 volts and connect shop air to the air
connection.
10. Switch the DT-45096 TransFlow to Flow and fill the
transmission with 8 quarts of transmission fluid.
10.1. Switch the DT-45096 TransFlow to idle.
11. Partially lower the vehicle and run the transmission
through all 8 forward gears, Reverse and Neutral.
12. Repeat steps 2-4 and 9-10 for 2nd drain and fill.
13. Repeat step 2-3, clean the transmission oil pan
and magnet, repeat step 4 and step 10-11.
14. Perform the Transmission Fluid Level and
Condition Check outlined below in this procedure:
14.1. Get the transmission fluid temperature to the
proper temperature.
14.2. Raise the vehicle and remove the DT-51190/
DT-45096-31 assembly.
14.3. Install the level set plug.
Tighten
Tighten the plug to 9 Y (80 lb in).
The TCC shudder condition should be directional
improved immediately after the fluid exchange
procedure. It may take up to 320 km (200 mi) for the
TCC shudder condition to be eliminated. It is not a
requirement for the dealer to drive the vehicle 320 km
(200 mi). The customer should be advised that the full
effect will take up to 320 km (200 mi) and a minimum of
two cold to operating temperature drive cycles.
Note: Silverado, Sierra, Yukon and Escalade Models
equipped with a thermal bypass valve, the transmission
fluid level should be checked only after the TFT has
reached or exceeded an operating temperature of 90°C
(194°F). Once the TFT has reached or exceeded 90°C
(194°F), then turn OFF the vehicle and allow the TFT to
cool back down to 35-45°C (95-113°F) before checking
the fluid level as required. Reaching or exceeding an
operating temperature of 90°C (194°F) opens the
bypass valve and allows the cooler to fill up with fluid,
which will result in a more accurate fluid level check.
1. Observe the TFT using the driver information
center (DIC) or a scan tool.
2. Start and idle the engine.
3. Depress the brake pedal and move the shift lever
through each gear range.
3.1. Pause for at least 3 seconds in each range.
3.2. Move the shift lever back to PARK.
3.3. Ensure the engine RPM is low (500–
800 RPM).
4. Allow the engine to idle for a minimum time of 1
minute.
Caution: THE ENGINE MUST BE RUNNING when the
trans oil level check plug is removed or excessive fluid
loss will occur, resulting in an under-filled condition. An
under-filled transmission will cause premature
component wear or damage.
5. Raise the vehicle on a hoist.
⇒ The vehicle must be level, with the engine
running and the shift lever in the PARK range.
Note: Continue to monitor the TFT. If the TFT is not
within the specified values, reinstall the trans oil level
check plug and repeat the previous steps.
6. Remove the transmission oil level check plug (1)
from the transmission fluid pan.
Bulletin No.: 18-NA-355
April, 2020
7. Allow any fluid to drain.
• If the fluid is flowing as a steady stream, wait
until the fluid begins to drip.
• If no fluid comes out, add fluid until fluid drips
out. Refer to Transmission Fluid Fill Procedure
in SI.
8. Reinstall the transmission oil level check plug.
Tighten
Tighten the plug to 9 Y (80 lb in).
9. Inspect for external leaks. Refer to Fluid Leak
Diagnosis in SI.
Parts Information
Note: Only select the parts that coincide with the repair
performed.
Causal
Part
X
Description
Mobil 1 Synthetic
LV ATF HP
(Available only
through Local GM
Oil Distributors)
N/A
Part
Number
Qty
19417577
(US - 1
quart)
19418066
(Canada 0.946L/1 qt)
20
Page 17
Warranty Information
For vehicles repaired under the Powertrain coverage,
use the following labor operation. Reference the
Applicable Warranties section of Investigate Vehicle
History (IVH) for coverage information.
Labor
Operation
Description
Labor Time
8480818*
Fluid Exchange
1.1 hrs
Add
CT6 AWD Triple Drain
and Fill
1.0 hr
Add
CT6 RWD Triple Drain
and Fill
1.6 hrs
Add
Corvette RWD Triple Drain
and Fill
1.6 hrs
Add
DT-45096 Prep (Not
required unless the fluid is
not Mobil 1 Synthetic LV
ATF HP)
0.1 hr
*This is a unique Labor Operation for Bulletin use only.
24 (CT6,
Corvette)
Drum 55
gallon
19417904
(US)
1
N/A
RETAINER,
TRANS FLUID
CLR PIPE FTG
24205103
2
N/A
SEAL, TRANS
FLUID CLR PIPE
23135703
1
Version
6
Modified
Released January 17, 2019
Revised March 01, 2019 – Added Canada, Middle East Operations, Mexico and Export
Region reference to Attention statement, added Canada and Middle East Operations to
Involved Region or Country, added printing information to the Important statement under
PicoScope Test section and added fluid part number for Canada, a Note and two
additional part numbers in the Parts Information section.
Revised May 21, 2019 – Added Date Breakpoints in Models section, Fluid Exchange
Procedure for V8 Camaro, additional information to TCC Shudder condition paragraph at
the end of each procedure, added missing 4 quarts of HP fluid to the vehicles with Rear
Differential Cooler sections and added Pico and GDS screen shots.
Revised July 08, 2019 - Updated the Warranty Information section, removed all of the
Diagnostic and Pico testing information.
Revised July 29, 2019 - Update Labor Operation time to 1.1 hrs.
Revised March 30, 2020 - Added Note to the Model table and in the Correction section
not to perform this bulletin twice.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
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