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File in Section:Service Bulletin-Bulletin No.:16-NA-014Date:July, 2016TECHNICALSubject:Brand:Delayed Engagement After Sitting With Engine OffModel:Model 8/2015EscaladeESVATS8L908L45 or 8L9011/23/2015CTS8L45 or ssion:to8L909/28/20153.6L (LGX)8L4511/09/20152.0L 8L90Sierra10/12/20158L90YukonYukon XL10/08/20158L908L90Involved Region or CountryNorth America and N.A. Export RegionsConditionSome customers may comment on a condition of delayed engagement when thetransmission is shifted from Park to Reverse or Park to Drive after the vehicle has beensitting with the engine off. This condition may typically occur after several hours or morecommonly overnight.Customers may describe this condition as: Vehicle delaying into gear. Not wanting to move. Feeling like the transmission is slipping. Delayed engagement followed by a harsh engagement.Operation will be normal for the subsequent engagements throughout the day and thecondition will not occur until the vehicle sits again with the engine off for several hours orovernight.CauseThis condition may be caused by the torque converter draining the transmission fluidback into the transmission pan.Copyright 2016 General Motors LLC. All Rights Reserved.

Page 2July, 2016Bulletin No.: 16-NA-014Not Wanting to Move or Slips - Torque Converter Drain Back4541012Example of acceptable torque converter fill time.If the customer describes the condition as a longengagement with a slip/soft engagement feel and/or thevehicle not wanting to move, the condition should beconsidered drain back and the following procedureshould be followed.1. Using GDS and monitor engine RPM andtransmission Input Speed Sensor (ISS) prior tostarting the engine.2. Start the engine with the transmission in park. ISS should be equal to engine RPM in 3seconds or less. If ISS takes more than 3 seconds to equalengine RPM than follow the procedure forreplacing the stator shaft support described inthe service procedure below. DO NOT replace the stator shaft support onvehicles taking 3 seconds or less for turbineshaft speed to equal engine RPM.

Bulletin No.: 16-NA-014July, 2016Page 3Delayed Harsh Engagement - Clutch Slow to Fill4541011Example of C5 clutch needing to completeAdaptive Learn on a 2016 MY vehicle or a C5Clutch that is slow to learn on 2015 and 2016 fill.If the customer describes the condition as a longengagement time with a harsh or bump engagementfeel when shifting the vehicle from park to drive orreverse. Using GDS and monitor engine RPM andtransmission Input Speed Sensor (ISS) prior to startingthe engine. Start the engine with the engine in park. ISSshould equal engine RPM in 3 seconds or less. If ISStakes more than 3 seconds to equal engine RPM thanfollow the procedure for replacing the stator shaftsupport. If the ISS is equal to engine RPM in 3 secondsor less shift the vehicle from park to drive or reverseleaving the service brake applied. ISS should drop tozero “0’ within 2 seconds, this is clutch engagementtime. Recording a GDS session log can be useful indiagnosing this condition.For 2015 MY vehicles Contact GM TAC for review andadditional instructions. Prior to contacting TAC record aGDS2 Session log of the delayed engagement.Note: This procedure will allow the pressures to adaptand improve the engagement time to reverse.For 2016 MY vehicle attempt to learn the C5 Clutchusing the following procedure:1. Allow the transmission sump temperature to risebetween 20 and 30 degrees C (68 and 86degrees F).Note: Do NOT apply the accelerator pedal.2. Perform 20 Park to Reverse shifts releasing thebrake with each shift.If the learn procedure does not correct the conditioncontact GM TAC for review and additional instructions.Prior to contacting TAC record a GDS2 Session log ofthe delayed engagement.CorrectionInstall a new stator shaft support assembly thatincludes an additional check ball. Follow theinstructions below to replace the stator shaft supportassembly.Service Procedure1. Remove the transmission from the vehicle andmount to the DT-48989 transmission holdingfixture. Refer to Transmission Replacement in SI.2. Remove the 15 bolts (1) securing the fluid pan andgasket to the transmission.

Page 4July, 2016Bulletin No.: 16-NA-0144358672Note: The fluid pan gasket is reusable. Inspect thegasket to determine if it may be reused. If the gasket isstuck to the case or pan, it should be replaced.3. Remove the fluid pan (2) and gasket (3). The fluidfilter does not need to be removed.43587696. Remove the 11 front cover bolts (1). Discard thebolts. The bolts have a dry sealant on them andmay only be used once.Note: There are 2 different front cover configurations.Early design front covers have 3 threaded holes forservice, late design front covers have 2 threaded holes. 7.8.9.10.11.43587674. Using the DT-48285 Torx Plus socket, remove thetwo fluid baffle bolts (1) and fluid baffle (2). Discardthe bolts.Note: The driven sprocket locking tab is located on theback of the sprocket. Rotate the sprocket as shown andsimultaneously pull back and up on the tab to releasethe retainer.5. Remove the driven sprocket (3) from the oil pumpshaft leaving the drive link (chain) loose inthe case.Use two GE-6125-1B slide hammers andDT-51791 slide hammer adapters in thethreaded holes of the front cover to remove itfrom the case for applications with 3 threadedholes. Use the GE-8433 puller bar and 2 bolts in thethreaded holes of the front cover to remove itfrom the case for applications with 2 threadedholes.Remove the front cover (2) and seal (3). Inspectthe seal and replace if worn or damaged.Remove the drive sprocket (5).Remove the drive link assembly (6).Remove the front support cover gasket (8). Discardthe gasket.Inspect the front (4) and rear (7) drive sprocketthrust washers. Replace if worn or damaged.

Bulletin No.: 16-NA-014July, 2016Page 5435877112. Remove the turbine shaft O-ring seal (1). Discardthe seal.13. Remove the nine stator shaft support bolts (2).14. Remove the stator shaft support assembly (3).4358773

Page 6July, 2016Bulletin No.: 16-NA-0144358775Legend(A)Old stator support asm(B)Note: The new stator shaft support assembly has asecond check ball (1) added (see illustrations).New stator support asmCaution: Size the converter fluid seal ring for at least5 minutes after installation to obtain proper seal ringsize. Failure to do so may cause internal transmissionleaks and transmission damage.Note: Use the large taper side of DT-50912-1 SealSizer for initial seal sizing, then flip the tool over for finalsizing. The DT-50912-1 seal sizer works for both the8L90 and 8L45.15. Using the DT-50912 Seal Installer (8L90) orDT-51196 Seal Installer (8L45), install a NEWtorque converter fluid seal (1) on the stator shaftsupport assembly. Size the seal using theDT-50912-1 Seal Sizer.16. Install 2 NEW 1-3-5-6-7 Clutch Fluid SealRings (2).4358778

Bulletin No.: 16-NA-014July, 2016Page 74358780Note: Align the bolt hole indicated by the arrow withthe arrow that is cast into the case and push downto seat.17. Install the NEW stator shaft support assembly (1).18. Install the nine stator shaft support bolts (2).Tighten the bolts in the sequence shown. Tightenthe bolts to 31 Y (23 lb ft).19. Install a NEW turbine shaft O-ring seal (3).

Page 8July, 2016Bulletin No.: 16-NA-0144358782Legend(A)Old cover - 8L90 Only(B)Note: The casting void has been eliminated from theunderside of the cover for the 8L90 only (seeillustration). The 8L45 is not required.4358784New cover - 8L90 Only20. Using the DT-43772 Torque Converter SealInstaller, install a NEW torque converter fluid seal(1) on the front cover.

Bulletin No.: 16-NA-014July, 2016Page 9435878721. Install a NEW front support cover gasket (1).22. Install the (rear) drive sprocket thrust washer (2) onthe stator shaft support assembly.23. Install the drive sprocket (3) and drive linkassembly (4).24. Install the (front) support cover gasket (5) on thefront cover (7).25. Install the front cover seal (6) on the front cover (7).Note: Ensure the drive link assembly is not pinched bythe front cover and moves freely on the drive sprocket.26. Install the front cover (7) on the 8L90 only.27. Install the 11 NEW front cover bolts (8). Graduallytighten the bolts in the sequence shown. Tightenthe bolts a first pass to 6.5 Y (58 lb in). Tightenthe bolts a final pass 30 Degrees.

Page 10July, 2016Bulletin No.: 16-NA-0144358789Note: Ensure the driven sprocket locking tab is in theunlocked position before installing the sprocket. Thedriven sprocket locking tab is located on the back of thesprocket and faces the pump.28. Install the drive link (chain) to the driven sprocket(1) and then install the driven sprocket to the oilpump shaft. Rotate the sprocket as shown andpush down on the tab until it locks the drivensprocket in place.29. Install the fluid baffle (2).30. Using the DT-48285 Torx Plus socket, secure thebaffle using two NEW fluid baffle bolts (3). Tightenthe bolts a first pass to 4 Y (35 lb in). Tighten thebolts a final pass to 45 degrees.

Bulletin No.: 16-NA-014July, 2016Page 11435879631. Install the fluid pan and gasket and secure with 15bolts. Tighten the bolts to 10 Y (89 lb in) in thesequence shown.32. Install the transmission into the vehicle. Refer toTransmission Replacement in SI.Parts InformationDescriptionPart NumberQtyTrans ModelComponentNumber inDisassembledViewsGASKET-A/TRNSFLUID PAN242600711 (if required)8L45/8L9048BOLT/SCREW-A/TRNSFLUID BFL1154840428L45/8L9012BOLT/SCREW-A/TRNSCASE FRT CVR11548201118L45/8L903SEAL-A/TRNS CASEFRT CVR242663661 (if required)8L905SEAL-A/TRNS CASEFRT CVR242519061 (if required)8L455GASKET-A/TRNS FRTSUPT CVR2427265818L9019GASKET-A/TRNS FRTSUPT CVR2427288318L4519WASHER-DRV SPKT THR(FRONT)242591191 (if required)8L45/8L906WASHER-DRV SPKTTHR (REAR)242594271 (if required)8L45/8L908SEAL-TURB SHF (O RING)24261849 (Part of24271697 kit)18L90500SEAL-TURB SHF (O RING)24261848 (Part of24277071 kit)18L45500SUPPORT ASMSTATOR SHF2427723418L9014SUPPORT ASMSTATOR SHF2427723018L4514

Page 12July, 2016Bulletin No.: 16-NA-014DescriptionPart NumberQtyTrans ModelComponentNumber inDisassembledViewsCOVER-A/TRNS CASE FRT242779641 (if required)8L904SEAL-T/CV FLUID2425921618L45/8L9018RING-1-3-5-6-7 CLUFLUID SEAL2426659328L9015RING-1-3-5-6-7 CLUFLUID SEAL2426659428L4515SEAL ASM-T/CV FLUID2426670918L45/8L902FLUID, A/TRANS (DEXRONHP ATF) (1 QUART)19300536-US19300537-CAAs Required8L45/8L90Warranty InformationLaborOperationDescriptionLabor Time8465020Stator Shaft rsion3ModifiedApril 22, 2016 – Removed stator part numbers from procedure. New part number forTrans Frt Gasket.June 16, 2016 – Clarifying Condition, added Cause statement and added diagnosticprocedures for C5 clutch and Torque Converter above Correction.GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform thesetechnicians of conditions that may occur on some vehicles, or to provide information that could assist in the properservice of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do ajob properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that yourvehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from theinformation.WE SUPPORT VOLUNTARYTECHNICIANCERTIFICATION

2015 2016 SOP 10/08/2015 8L90 Escalade ESV 8L90 ATS 11/23/2015 8L45 or 8L90 CTS 8L45 or 8L90 Chevrolet Camaro 11/23/2015 8L90 9/28/2015 3.6L (LGX) 8L45 11/09/2015 2.0L (LTG) 8L45 Corvette 10/27/2015 8L90 Silverado 10/12/2015 8L90 GMC Sierra 10/12/2015 8L90 Yukon 10/08/2015 8L90 Yukon XL