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  1. #1

    Default Transmission mount bolts falling out!

    This is an odd issue that I have never seen before... The two bolts that hold the tail end of the transmission to the cross member keep falling out. I have replaced them 4 times now. Usually, one is gone and the other one is loose. Sometimes they are both gone...

    Heres the thing... I am using M10/1.50 bolts each time I replace them. I use loctite, lock washers and really torque them down. The holes are not stripped. I can get them in there tight but they keep falling out. I have a feeling that the M10x1.50 is not the correct bolt, even though the factory manual says they are.

    Anyone else have this problem? What do ya do about this?! Anyone know the correct bolt size?
    "It went together didn't it? Well then there has to be a way to take it apart!" - Me.

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  2. #2

    Default

    That is an odd issue! How does the actual mount look? Is it badly deteriorated? One way to fix them from coming loose would be to use castle nuts and cotter pins. But that is just a remedy for now that doesn't sound like it actually fixes your underlying problem.





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  3. #3

    Default

    Wow, strange indeed!?!? So I take it your tranny mount has threads in it instead of a through hole that a bolt and nut would use?

  4. #4

    Default

    Yes. The tail of the transmission has mounting tabs with threaded holes. The bolt goes up through the crossmember and threads into the tabs on the tranny. The mount is fine and the threads on the tranny are not stripped out. The holes do not go all the way through the mount tabs... Otherwise I would get longer bolts and put nuts on the top. This one has me scratching my head...
    "It went together didn't it? Well then there has to be a way to take it apart!" - Me.

    Check out my image gallery HERE.



    "The true measure of a man is how he treats someone who can do him absolutely no good." ~Samuel Johnson (1709-1784)

  5. #5

    Default

    You could try tapping the holes to 7/16".
    ...
    ....

  6. #6

    Default

    Quote Originally Posted by Chris Miller View Post
    You could try tapping the holes to 7/16".
    I may have to do that. I could also just drill the holes all the way through the mounting tabs and run longer bolts with washers and nuts...
    "It went together didn't it? Well then there has to be a way to take it apart!" - Me.

    Check out my image gallery HERE.



    "The true measure of a man is how he treats someone who can do him absolutely no good." ~Samuel Johnson (1709-1784)

  7. #7

    Default

    you could try tack welding the heads of the bolts. other wise, go to the hardware store and try a few different metric and standard bolts in the holes.

    Alex


    2011 GMC Sierra SLE 5.3 Z71 4X4 Stealth Gray Metallic / 2004 Chevy Impala LS 3.8 Cappuccino

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  8. #8

    Default

    Quote Originally Posted by Sierraowner5.3 View Post
    you could try tack welding the heads of the bolts. other wise, go to the hardware store and try a few different metric and standard bolts in the holes.

    Alex
    I think I will try the bigger bolts route. The bolts are a bit wobbly when they are not tight. Perhaps someone drilled them out and put larger threads in at some point.
    "It went together didn't it? Well then there has to be a way to take it apart!" - Me.

    Check out my image gallery HERE.



    "The true measure of a man is how he treats someone who can do him absolutely no good." ~Samuel Johnson (1709-1784)

  9. #9

    Default

    Could you try some stage 8 fasteners perhaps? They're designed to use some type of metal potrusion to keep them locked such as you have with headers. But I know guys that have used them in other applications as well.
    http://www.stage8.com/

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