M20 is for a wide ratio 4 speed regardless of being a Muncie or Saginaw. By the time our generation went into production the Saginaw was the only M20. FYI M21 is close ratio, M22 is close ratio special heavy duty, M24 is for the BW Super T10 (post Muncie usage about '75)Thanks for decode....funny code for trans is m20.....but doesn't get muncie. What is it?
This is a better explanation than mine. M20/M21/etc., etc., RPOs have been around since the early 60s, and used in cars and trucks, and cast iron or aluminum. Casting numbers on the case are pretty much the only way you can tell which transmission you have as far as model, gear ratios etc. In the early days, you ordered a car with M20 wide-ratio, but you could get close-ratio instead depending on the rear end gearing choice. In any matter, the fact that M20 is on the body tag means you got a 4-speed manual, and it makes your car a whole lot more unique than the automatic RPOs.M20 is for a wide ratio 4 speed regardless of being a Muncie or Saginaw. By the time our generation went into production the Saginaw was the only M20. FYI M21 is close ratio, M22 is close ratio special heavy duty, M24 is for the BW Super T10 (post Muncie usage about '75)
can we see the car?
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