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4l60e 1996 tahoe transmission problems help!!!!

Discussion in 'GM Powertrain' started by JOHNNYBLACKEYE, Oct 12, 2009.

  1. JOHNNYBLACKEYE

    JOHNNYBLACKEYE New Member

    Need some help .have 4x4 tahoe 1996 transmisson wont shift to 2nd unless i have it right at 3ooo rpm and let off gas.also have no overdrive isnt sliping in any gears and pulls just fine .i have been reading up on this site about the 4l60e trans troubleshooting a few guys said to change the 1-2 shift sensor did that afew guys said to change t.p.s did that has fresh fluid and filter in it all the wireing looked good inside pan. There was smoe metal shaveings on the magnet when i did the sensors.....any guess on where to look next any help will be great thanks in advance ALSO THERE IS NO CODES

    sorry about the caps sent from phone
    thanks john
     
    Last edited: Oct 12, 2009
  2. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    You can throw parts at it all day long and never fix it. Why not scan it for codes and fix the problem? Also since you have a 96 it probably needs the GM PCM Ground Wire Update.

    This bulletin is being reissued to ensure that correct procedures are followed for this condition. Please discard Corporate Bulletin Number
    66-71-03A (Section 7 -- Automatic Transmission).


    --------------------------------------------------------------------------------

    When performing a transmission replacement labor operation K7000 on these vehicles with a 4L60-E or 4L80-E, you must include front chassis wire repair labor operation N6112. Inspect the VCM to verify the latest part number revision (16244210).

    Condition Some owners may comment that the automatic transmission has either a slip or flare on the 1-2 and/or 2-3 upshift, or no 3rd or 4th gear, or launch shudder. Upon investigation, the technician may find a DTC P1870 stored in the VCM.

    Cause A poor internal ground between the two circuit boards of the VCM may cause the VCM to command erratic line pressure at the pressure control (PC) solenoid valve.

    Correction Using harness jumper wire and instruction kit, P/N 12167310, revise the wiring harness at the VCM connector. Corrections were made to the VCM beginning 2/14/96. The corrected VCMs are identified with service number
    16244210 on the VCM identification label.

    Procedure The following is a summary of the instructions included with the service kit:

    1.. Remove the negative terminal from the battery.
    2.. Move the wire located at connector J3 (WHITE/GREY/CLEAR), pin 18 to connector J1 (BLUE), pin 23.
    3.. Install the jumper wire between connector J2 (RED), pin 26 and connector J3 (WHITE/GREY/CLEAR), pin 18.
    4.. Install the tag included in the kit around the VCM wiring harness. This tag notes that the wiring harness has been modified.
    5.. Reconnect the negative battery terminal. Road test to verify that the condition has been corrected. If any of the following conditions are noted, the transmission should be repaired or replaced using the most cost effective method. Canadian dealers should repair the transmission.

    . Transmission fluid oxidation or excessive sediment.

    . Transmission slip or flare after this service fix is performed.

    . DTC P1870 is stored on a 4L60-E (M30).

    The following tools are available from Kent-Moore (1-800-345-2233) for use in removing and relocating the VCM wires:

    . J 41758 Terminal Tool; used to remove the wire from the VCM connector.

    . J 41759 Punch; used to punch a new hole through the connector seal.

    Parts Information Part Number Description Qty

    12167310 Harness Jumper Wire Kit
     
  3. JOHNNYBLACKEYE

    JOHNNYBLACKEYE New Member

    Well i did the jumper wire from the dealer it still does the same thing !no codes and same problem any other help would be great
     
  4. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    If you can get someone to scan it and watch the data you may find your problem. It may be a bad MLP or VSS. A scanner will show what's happening.
     
  5. brianj

    brianj Rockstar

    Sounds like a vehicle speed sensor. However, most of the time this will post a code.You realy need to have this scanned for codes. Shotgun mechanics gets very expensive very quickly. You said that there are no codes. Did you hook up a scanner or are you just relying on no check engine light? you can have codes that will not set the engine light, and many of them are in the tranny.If you have no codes, you are probably looking at internal problems. there is a good site to look up diagnostics- google ATRAonline and you will find them. Good luck.
     

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