70 judge Trans M20 or M21? - Pontiac GTO Forum
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post #1 of 4 (permalink) Old 08-11-2014, 08:38 PM Thread Starter
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70 judge Trans M20 or M21?

I'm currently building a replica of the RAM AIM IV Judge and I've been told that both the M20 and 21 came in the Judge with this engine. I was under the impression it only came with the 21????

Also the shifter knob for the 4 speed mine currently has a black ball with white numbers. Was this an option in 70 or is it an aftermarket product? I have always seen the hurst T handle shifter with either just Hurst on it or with the 4 speed pattern on the Judges, which is correct for a 4 speed Judge from 70'?
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post #2 of 4 (permalink) Old 08-12-2014, 01:29 AM
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The 1970 Judge came standard with a 3 speed heavy duty manual transmission with the Hurst handle Tee stick shift. If you bought the RAIV option you were forced into the M21 close ratio 4-speed. The M20 was an option on the Judge but not with the RAIV option. You could order the M09 option which is the custom wood knob. Otherwise you would receive the standard black knob for the non Judge.
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post #3 of 4 (permalink) Old 08-13-2014, 09:20 AM
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....and with the Ram Air IV and M21 would have been a 3.90 gear....to complement the M21's tall first gear.
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post #4 of 4 (permalink) Old 08-16-2014, 11:25 AM
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Hurst T-handle would be right for your Judge replica. Choice of transmission depends on your rear end gears. I would run an M-20 with anything under 3.73's.

1969 GTO Judge 4spd - Carousel Red/Black
1969 GTO 428 TH400 - Crystal Turquoise/Parchment
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