6T70 Product Issues and Updates Presented by: Presented Steve Garr Garrett ett ATRA
Connections
Questions
Survey
Service Programming Any time you replace replace the transaxle transaxle you will need to re-program the TCM remember the TCM is internal to the transaxle.
Fast Learn Procedure Service Fast Learn Adapts is a procedure for 6 speed automatic transmissions transmissions in which a series of tests are run to allow the transmission control module (TCM) to learn individual clutch characteristics. Once the clutch data is learned, Service Fast Learn Adapts Adapts translates it into the adaptive data cells, which the TCM uses for clutch control during shifts. The scan tool provides initiation of the Service Fast Learn Adapts procedure. This procedure is to be used following transmission repair. Once the procedure is complete, shut OFF the engine and power down the TCM. You will lose communication to the scan tool. Restart the engine. This will complete the Service Fast Learn Adapts procedure. procedure.
Fluid Checking Procedure 1. Level surface, apply parking brake. 2. Start engine, move gear selector. 3. Idle 1 minute. 4. TFT between 180°F and 200°F 5. Read level on dipstick If the fluid was changed, Reset the trans oil life monitor Drive in 2nd to reach proper temp.
Non-serviceable Filter Only replace after internal repair Fluid Only Service 100,000 mile Regular service 50,000 mile Severe service
Torque Converter Removal Torque Converter Converter needs to raised raised vertically vertical ly Use J-46409 J-46409 to lift Torque Torque Converter Converter
No seal on turbine shaft, lip seal is locate inside of converter and can be damaged if converter is removed r emoved or install horizontally
6T70 Converter Discol ored Some 6T70 6T70 appl appl icati ons (RPO (RPO MH2 MH2,, MH4, MH4, MH6 MH6 or MY9) MY9) may exhi bit a dark o r blue b lue c olor olo r i n the metal metal of the tor que converter. converter. You You may noti ce what looks like dark ci rcles in the disco loration. This condit ion is typi cally on the hub side of the converter and is not present on all 6T70 6T70 torqu e converters .
If the whole converter is not discolored and evidence of an overheating condition is not present, DO NOT replace the torque converter.
6T70/75 Bind Bi ndin ing g on o n a 3-4 3-4 and and 4-3 4-3 Shi Shift ft,, Possib Poss ible le P079 P0797 7 Set Set On 6T7 6T70 0 and and 6T75 6T75 appl appl ications icati ons the th e cus tomer to mer may com ment regardi ng a bind on a 3-4 3-4 or 4-3 4-3 shift. A worn wo rn ri ng gr oove on the case cover hu b slee sl eeve ve will wi ll result r esult in a leak leak betwee b etween n the th e 3-5 3-5 Reverse Reverse clu tch tc h and the th e 4-5 4-5-6 -6 clutch fluid circuits. This will r esult in the tie-up tie-up c ondition the customer is experiencing. xperiencing. Remove Remove the hub from the rear case cover co ver and inspect the ring gr ooves ooves and rings . Measure Measure the dis tance with a feeler feeler g auge betw een een the edge of the gro ove and the rin g (Maximum (Maximum clea cl earance rance is .007 .007”” ). If the distance is too great great replace the th e case cover cov er..
6T70-6T75 No Reverse, 3rd or 5th Gears Possible P0776, P2723, P2715 set This condition primarily affects transmission built prior to the 2010 model year Updated parts are available from GM and Ford to address the issue Weld Breaks
New Shell comes with the #3 thrust bearing Keep diagnosis simple: Unplug the transmission to see s ee if Reverse is being prevented electrically. electrically. If reverse engagement engagement is ok, the shell is not the problem.
6T70/75 PRND PRNDL L Doesn Doesn’t ’t Ill umin um inate ate GM Z body bo dy (Malibu (Mali bu,, Aur a 6T40/45 6T40/45 (RPO MH7/MHC) MH7/MHC) 6T70/75 6T70/75 (RPO MH2/MH4/ MH2/MH4/MY9/MH MY9/MH6) 6) applications may exhibit a condi tion wh ere the PRND PRNDL L displ ay does not ind icate the gear gear posit ion th e customer has selected. selected.
This c ondition in many inst ances is intermittent and and dif ficult to d uplicate uplicate..
Inspect c ircui ir cui ts 5981 5981,, 598 5982, 2, 5983 5983 and 5984 5984 for poor poo r or damaged con necti ons betw een een the Instrument Panel Cluster, Body Control Module and the Shift Lever assembly. Inspect connector con nector s X206, X206, X303 X303 and X304 X304 for damaged or l oos e termin als.
An Updated Calibration is available to address address this concern
Check heck line lin e pre pr essure ssu re at at idle idl e, if low inspe ins pect ct the th e pump pu mp outl ou tle et seal seal for f or damage. damage.
6T70 DTC’s DTC’s P0752, P0752, P087 P0872, 2, P0877, P0877, P0989 P0989,, Flui Flu i d Press Pr essur ur e Sw Sw i t c h Issues
Some custo mers may com ment about an SES SES light and/or no reve reverse and may may also co mment on a slip / flare flare or harsh shift s in drive dri ve range range 3rd and/or and/or 5th gear. gear. Upon Upon i nvestig ation, th e techni cian may fin f ind d DTC P077 P0776 6 (Clut (Clutch ch Pressure Pressu re Cont rol ro l (PC) (PC) Sol Solenoi enoid d2Stuck Off) set. set. Any Any one of th e follow ing cod es may may s et i ndependent ndependent of each ot her as a result resu lt of t his hi s w ave plate pl ate brea br eaki king ng:: P0777 P0777,, P27 P2723 23,, P0717, P0716, P2715, P2714. This con dit ion may m ay be caused by a broken 35R 35R clutc h wave w ave plate allow ing the apply apply p isto n to over-strok over-strok e, causing the piston to leak leak and causing los s of apply
Install th e upd ated ated wave plate anytim e the transm iss ion i s apart apart f or a repair repair If it is a 2010 2010 or earlier appli cation . P/N 24254103 Inspect th e case for s igns ign s of d amage amage
Normal
Cause Cause for con cern
6T70/75 Planetary Planetar y Damag Damage e Due To To Wave Plate Breakage B reakage To prevent damage from occur ring to th e new new gear set or i f you are repairing repairing one of these units and the planetary planetary is not yet damaged, damaged, you shou ld i nstall t he new new design w ave plates in all of the clutc hes.
Clutch & Part Part Number
1-2-3-4 #24259063 2-6 #24259816 3-5 Reverse #24254103 Low-Reverse #24259817
NOTE: THE 3-5 REV WAVE IS THE MOST COMMON ONE TO BREAK
6T70/75 Broken Wave Plate In many many ins tances the transmis sion was disassembled origi nally to address a no 3rd, 3rd, 5th or reverse reverse condi tion whi ch is typicall y assoc iated iated w ith a P077 P0776 6 DTC DTC.. Upon Upon i nspection a broken wave plate in the 3-53-5-Re Reverse verse cl utch utc h is generally d etermined t o be the cause and and th e reacti reacti on carrier w as damage damaged d fr om d ebris.
No Movemen Mov ementt , DTC DTC 2723 2723 A no m ovem ov emen entt and /or P2723 may be s et af ter r epai r. This Th is co nd i ti on i s us ual l y ass oc i ated wi th GM R/V R/V/Z /Z body bod y styl s tyle e applic ations (Traverse, (Traverse, Acadia, Acadia, Outlo ok, Enc lave, Malibu Malibu , G6, G6, Aura, Vue) and may exhibi exhibi t a no dri ve conditi on after a repair, repair, which typi cally incl udes replacement o f th e reacti reacti on p lanetary c arri er. er. In addi addi tio n a P272 P2723 3 DTC DTC may be set.
Missin is sing g Ring Gear In many many pu blic ations t he reaction reaction carri er and and the input ring gear gear are shown as a one piece assembly. In reality, the reaction carrier, input ring gear and ring gear snap ring are serviced as separa separate te pieces. If the technician fails to i nstall the ring gear gear ont o the reaction c arrier a no drive cond ition wi ll result. To To repair the conditio n, install th e ring gear. gear.
6T70/75 Planet Damage, No Movement, DTC 2723 Ring Gear Gear Snap Ring Ring (very (very difficul t To r emove)
Parts rt s Catalog Catalogs s Show This Planet Assembl y As One Piece Piece Input Ring Gear
Reaction Carrier
* 2007 and later models have eliminated one bolt from the torque converter converter housing area. The updated transaxle will utilize u tilize a 9 bolt support. The updated converter converter housing is not tapped for the bolt bolt so it is not necessary for you to do any modifications to assist you with interchange of the parts. The updated support will will backservice previous models as you will simply eliminate eliminate the bolt. When installing the updated support on an earlier application, simply follow follow the torque sequence for the 9 bolt system
* The lube trough design was updated on 2008 applications. The updated design uses only one bolt to retain the trough in the case. In later case designs designs only one one bolt hole is drilled in the the case. The updated trough will backservice previous design applications.
An update to the design of the Output and Reaction carriers occurred occurred for the 2009 model year year.. The Output carrier bearing pocket has been machined .01” (.3mm) deeper to accept a thicker sun gear bearing design. The Reaction carrier sun gear bearing has also been modified. modified. The bearing pocket on the updated carrier has been machined .009” (.25mm) deeper to allow for a more robust bearing design. The updated carriers will backservice if the updated bearings are used.
A updated cooler cooler line was developed developed to reduce reduce the chance chance of leakage from from the cooler circuit. The updated lines have longer snouts and the cooler line holes in the case were were modified to to accept the longer snouts. This update was was designed for 2008 and later applications and it will NOT backservice into into the previous design cases.
The 6T70 (RPO M7W or M7U) and 6T75 (RPO M7V and M7X) received a major contr ol s ystem upd ate for the 2013 2013 model year. year. As w ith up dates dates on other applications this major change was NOT implemented in all 6T70/75 applications. Because of parts availability issues, 6T70/75 applications with RPO codes other than M7W, M7W, M7U, M7U,M7 M7V V or M7X wi ll not receive the up date unti l 2014 2014 prod uction uct ion . This means means t hat two versions of th e 6T7 6T70/ 0/75 75 transmis sion wi ll be available available in 2013, Generation I and Generation II
GEN GEN I: I: Units that do n ot co ntain the con trol s up date package package
GEN GEN II: II: Units t hat cont ain the cont rols update package package
The TC TCM calc calcul ula ates fil f illl tim t ime e based based on the th e learn learne ed volume. vol ume. The CP CP Lea Learn is conduc con ducted ted dur ing ste st eady condi co nditi tions ons in 3rd, rd , 5th and 6th gear. gear. The CP Learn Learn for fo r the t he 4-5 4-5--6 clutc clu tch h is i s enabl enable ed in i n 3rd gear. gear. CP CP Learn for fo r t he 1-21-2-33-4 4 clut cl utc c h and an d 2–6 clut cl utch ch is enabled in i n 5th ge g ear. CP Learn Learn for fo r the t he 335-R clut cl utch ch is enabled in i n 6th ge g ear. A rough rou gh roa ro ad condition condit ion could give a false false rea reading for transmission transmissi on input spee speed interruption. interrupti on. Whe When n rough rou gh road condi co nditio tions ns are detecte detected, d, CP CP Learn Learn is aborte bort ed until unti l road conditi ons impro i mprove ve..
2-6 Clutch, Snap ring And Case Snap ring Groove Updated
