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TH 400 Identification

Discussion in 'General Chevy & GM Tech Questions' started by 2COR517, Jun 18, 2009.

  1. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    I have a TH 400 that came in an 85 1/2 ton 2wd pickup. Obviously, it's not the original tranny, the truck had a HO 305 swapped in. Anyway, I want to sell the tranny. Are there any numbers on it that might indicate the year and vehicle it came out of?

    Thanks!
  2. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    There should be a tag on it with a 3 digit code. If you can't find it it doesn't really matter as the Chevy 400 2WD transmissions were all basically the same. Bolt on yoke with a short tail shaft.
  3. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    I will look for the tag. Is it reasonable to assume if first and reverse work, the transmission is OK?
  4. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    The best way to tell if the transmission is OK other than driving it is to pull the pan. If the fluid is clean and there's no metal and friction material in the pan then it's safe to assume the transmission is OK.
  5. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    Hey thanks for the tip. The fluid looked fine when I was draining it out of the tailshaft. I will drop the pan though.

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