Adnimation ATF

Collapse

MECF_728x90_top

Collapse

Announcement

Collapse
1 of 2 < >

CorvetteToday Podcast Delves Into C4 With Aficionado Brad Hansen

CORVETTE TODAY delves into the C4 Corvette with affectionato, Brad Hansen. https://podcasts.adorilabs.com/corve...I0r3Da0OXhSCLC Brad is a LA videographer, but uses his C4 as a Daily Driver. Consequently, he has become a true go-to guy for all C4 do-it-yourselfers! Brad has a great YouTube channel and social media presence. You'll find out all about that and more on this episode of CORVETTE TODAY!

Listen Here: https://adori.page.link/corvette-today
Website & Merchandise: www.CorvetteTodayPodcast.com
Get CORVETTE TODAY emails: https://CorvetteToday.ck.page
Join the CORVETTE TODAY Facebook Group: https://www.facebook.com/groups/2718423201763136
Watch CORVETTE TODAY on YouTube: https://www.youtube.com/channel/UCXCRn-2X0SjjEXUt_...
See more
See less

A8 Transmission Shudder Service Bulletin

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • A8 Transmission Shudder Service Bulletin

    Thanks to GM TechLink, we have this news of a new A8 shudder diagnosis and repair procedure.

    Originally posted by TechLink
    Torque Converter Clutch Shudder and New Mobil 1 Fluid Exchange

    A new transmission fluid exchange procedure and a new formula of Mobil 1 Synthetic LV ATF HP transmission fluid have been released to address torque converter clutch (TCC) shudder conditions on 8L45 and 8L90 8-speed automatic transmissions (RPOs M5N, M5T, M5U, M5X) in some 2015-2017 Escalade, Yukon; 2015-2018 Silverado, Sierra; 2015-2019 Corvette; 2016-2018 CT6; 2016-2019 ATS, CTS, Camaro; and 2017-2019 Colorado and Canyon models.

    The new fluid exchange procedure requires the use of the DT-45096 TransFlow Cooler Flush Machine and DT-52263 Transmission Fluid Exchange Tool Kit. (Fig. 10) The tool kit began shipping to dealerships at no charge in late January 2019. All GM dealerships should receive the tool kits by the end of March 2019.

    Click image for larger version

Name:	6652E430-6F35-42DD-BCEC-A2429F7CE47E.png
Views:	9123
Size:	284.7 KB
ID:	26380

    Shudder Test

    The new service procedure addresses shake and/or shudder conditions during light throttle acceleration between 25 and 80 MPH (40 and 128 KM/H) at a steady speed when the transmission is not shifting gears. To ensure TCC shudder is diagnosed correctly, drive the vehicle on a smooth road with transmission sump temperature between 122°F (50°C) – 158°F (70°C). Constant throttle input on a smooth grade is needed.

    A shudder condition may also be a chuggle, surge or vibration condition. Use GDS 2 or the CH-51450 PicoScope to confirm that the concern is TCC shudder and not a tire/wheel vibration or a driveline vibration, for example. A screen print from GDS 2 or the PicoScope showing the TCC shudder event must be attached to the Repair Order hard copy. (Fig. 11)

    If TCC shudder is present, a vibration peak will appear within +/- 2 Hz of the frequency listed in Bulletin #18-NA-355. Refer to the bulletin for additional information, including required shudder test conditions for each vehicle being diagnosed as well as the fluid exchange procedures.

    Fig. 11



    Fluid Exchange

    The TCC shudder condition is related to moisture content in the transmission fluid. The current fluid tends to be hydroscopic, or absorbs moisture, which increases the chance of TCC shudder. There are three different fluid exchange procedures to follow, depending on vehicle application, so that an acceptable concentration of the new HP fluid is achieved in the transmission.

    The new Mobil 1 Synthetic LV ATF HP transmission fluid is now available to U.S. dealerships through your local GM Oil Distributor. The new Mobil 1 Synthetic LV ATF HP transmission fluid is available in quart bottles (GM Part Number 19417577) and, for a limited time, in 55-gallon drums (GM Part Number 19417904) in most locations. Drum production ended in January 2019. The GM part numbers are not on the product.

    The Mobil 1 Synthetic LV ATF HP fluid and the required tool kit will be available to all Canadian dealerships by the end of March 2019. GM Part Numbers for 0.946 liter bottles will be provided at that time.

    TIP: Mobil 1 Synthetic LV ATF HP transmission fluid is required for all 8-speed transmission repairs regardless of the repair being completed.

    Quart bottles, which can be identified by a new blue banner across the front of the bottle (Fig. 12), will be limited to 20 cases/120 quarts per dealer per week during the initial launch of the new product. The new bottles also feature the HP license number J-62120 on the back label.



    Fig. 12



    For a video demonstration of the new fluid exchange procedure, check out the December 2018 Emerging Issues Broadcast, course number 10218.12V, available through the Center of Learning. In Canada, refer to the January 2019 TAC Talk seminar.



    – Thanks to Mark Gordon
    https://gm-techlink.com/?p=11127

    Last edited by John; 02-13-2019, 03:40 PM.
    GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

  • #2
    Thanks to SgtMajUSMC for finding/sharing these screen prints which provides the Service Bulletin # and a little more information.

    Click image for larger version

Name:	6ED5DF67-067C-4917-95B7-CFA5444070DB.jpeg
Views:	9042
Size:	506.5 KB
ID:	26382Click image for larger version

Name:	FB6A3C97-D20B-475B-8E4E-EEFCC5CEE31B.jpeg
Views:	9142
Size:	403.2 KB
ID:	26383

    GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

    Comment


    • #3
      I have experienced a slight shudder a couple of times with my 2016 Z06 when I was in a small group of Corvettes on the interstate. The lead vehicle was pulling a trailer so speeds were variable and I couldn't use cruise control. It hasn't been enough of an issue in three years of ownership to consider taking it in.

      My fear is that they would not be able to replicate it and would not want do the fluid change.
      1966 coupe - Sunfire Yellow / Black
      2004 Z06 - Millennium Yellow / Black

      NCM Lifetime Member since 2003

      Comment


      • #4
        Great information to share with my fellow corvette club members!
        Proud owner of
        1966 Ermine White/White Blue Interior L72 Coupe
        2013 Artic White/Diamond Blue Interior LS7 Convertible

        Comment


        • #5
          "The TCC shudder condition is related to moisture content in the transmission fluid. The current fluid tends to be hydroscopic, or absorbs moisture, which increases the chance of TCC shudder".

          My 2018 GS A8 has a build date of 7/17. So far (7500 miles) I do not notice any shudder.

          My question is: If the shudder is solely related to moisture in the fluid, why haven't we seen 10s of thousands of these issues reported? Although it seems there are lots of shudder problems, as a percentage you would expect more if it was a problem with the fluid only.
          2018 Grand Sport, Torch Red, black int, A8, Nav/PDR

          Comment


          • #6
            The A8 has been in many ways the more inconsistent, recent GM transmission I have heard of. It appears that 95% of owners experience not a single issue, yet others have shuddering, cold start (+8 hours) jerkiness into gear, and yet others have torque tube and other factors to deal with. I have many friends who have thoroughly enjoyed their ownership - again without a single issue ever, yet a couple of friends (one who is a member here) who has had one problem after another (one even on his second A8 after his fifth long term delaerhship visit for repairs over several years.

            It was physically re-designed starting with June, 2017 manufacture, had two fluid change recommendations, and now this latest TSB.

            I am sorry that a smalll percentage number have had significant issues with it.
            GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

            Comment


            • #7
              if yall wanted the bulletin all you had to do was ask lol....and its not as common on corvettes as it is the pickups, been seeing em basically one a week here at my dealership
              Your friendly neighborhood Technician

              Comment


              • #8
                Thank you very much rvb1331. At times we do need help in getting TSB’s. Glad you are offering to be our forum’s source for them. Very nice/helpful of you!
                GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

                Comment

                MECF_728x90_bottom

                Collapse
                Working...
                X