I have a 1968 442 4 speed with an m20, original motor and tranny, but the rear end is stamped TA. What was offered gear-wise with a m20 4 speed in a 442? I don't think this is the original rear, or even available in a 442. What were the rear end gear options for this car?

 

TA is a 2:78 standard type differential which is totally incorrect. That rear end is for a 4800 series model designation which is a Vista Cruiser. My original 68, 4-speed has code TO which is a 3:91 anti spin. This gear is a blast with a 4-speed car. You are missing out on a lot with that gear you have.

 

Non A/C 3.08, 3.23 were optional and the 3.42 was standard

If the car has A/C 3.23 was standard and 3.08 was optional

Section 4, page 104 of the assembly manual

You must be running a M21, correct?

 

Gear availability (and much more) is also shown in the SPECS brochures on Wild About Cars.
http://wildaboutcarsonline.com/cgi-b...aldisplayed=50

The Assembly Manual is there too!

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My 68 4speed is a open 3.91 gears and even a 45mph punch puts a hell of a smile on your face.

 

Thank you Gentlemen, Your help is greatly appreciated!

 

If this is, in fact, a vista cruiser rearend it is a very rare bird -- the axles and bearings are different from a pass car. It is a must for a resto vista cruiser.
IIRC -If the orig trans is an M20(wide ratio) -- then the original gear ratio is higher than 3.90 (like mentioned above). 3.90 and lower received the M21 trans (close-ratio 2.20 low).

 

Actually, 3.42 could be had with either M20 or M21 in 1968.