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1FZ-FE crankshaft to torque converter bolts: M12x1.25?

Discussion in '80-Series Tech' started by anothernord, May 17, 2018 at 11:15 AM.

  1. anothernord

    anothernord

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    Can anyone confirm what the thread size and pitch of the 1FZ-FE crankshaft to flex plate bolts?

    My best guess based on looking at the flex plate is that it's a fine thread M12. So M12 x 1.25. Can anyone confirm or deny this?
     
  2. bigredmachine

    bigredmachine

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    most other Toyotas are 10x1.25. do you have a bolt or are you looking for a replacement because if you replacing you should just buy one from the dealership. if the bolt is too long it can damage the torque converter
     
  3. anothernord

    anothernord

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    Thanks for the reply, I'm working on a transmission adapter plate and don't really want to spend $2 per bolt when you can get a whole bag from McMaster for pennies on the dollar. I can just design the depth of the threaded hole to whatever I want.

    The clearance holes in the torque converter to the crank are about 12.8mm, which makes me think they are for M12s, but they're also sorta oblong shape, so maybe you're right about them being M10s...
     
  4. bigredmachine

    bigredmachine

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    I haven't had to drop a lc trans so the converter bolts may be bigger but everything else that ive had to drop the trans on has been 10x1.25. I would still be careful with making your own bolts
     
  5. anothernord

    anothernord

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    Right, I'm talking about the 10 bolts that hold the flex plate to the engine crank, not the 6 that hold the torque converter to flex plate. I just need to know the thread pitch of Toyota's bolt so I can design the flex plate adapter for them to go into.

    I'm basically simulating the 1FZ crank with the part I'm making.
     
  6. anothernord

    anothernord

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    For all you searching out there (I know I know, this is a profound find) the thread on a 1FZ crank to flex plate bolt is M12x1.25. I got ahold of a factory bolt and measured it.