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**'68OrangeSunshine** · 06-21-2003, 03:54 AM

The '67 model year used the Muncie SM (synchromesh) 420 4-speed transmission. The '68 and later (to '87 maybe?) use the Muncie SM 465. The 420 was shorter than the 465 and had lower intermediate gear ratios. They have been considered a real good swap for other-make off roaders, [Jeeps, Toyos, IHs etc] and so may now be hard to find. 420s had a different shift pattern than the 465: while the 4 gears were in the standard "H" pattern, I think the 420's reverse was left of 1st and up, while the 465 goes into reverse off right of 4th and down. That's one way to tell them apart in a junkyard.
I don't know if the number of splines in the tailshaft was the same or different.
A SM 465 could be made to fit in a '67 but not without modifying either the driveline length or the engine mounting position. I don't think it's a simple bolt-in.
The good news is that the same bellhousing is used for both the L6 engines and big and small block V8s.
Hope this helps.

06-21-2003, 03:54 AM	#3
'68OrangeSunshine Senior Member Join Date: Feb 2002 Location: Tucson, AZ USA Posts: 7,622	The '67 model year used the Muncie SM (synchromesh) 420 4-speed transmission. The '68 and later (to '87 maybe?) use the Muncie SM 465. The 420 was shorter than the 465 and had lower intermediate gear ratios. They have been considered a real good swap for other-make off roaders, [Jeeps, Toyos, IHs etc] and so may now be hard to find. 420s had a different shift pattern than the 465: while the 4 gears were in the standard "H" pattern, I think the 420's reverse was left of 1st and up, while the 465 goes into reverse off right of 4th and down. That's one way to tell them apart in a junkyard. I don't know if the number of splines in the tailshaft was the same or different. A SM 465 could be made to fit in a '67 but not without modifying either the driveline length or the engine mounting position. I don't think it's a simple bolt-in. The good news is that the same bellhousing is used for both the L6 engines and big and small block V8s. Hope this helps. __________________ Every 25 years I like to rebuild that 292, whether it needs it or not.