Im confused...... So my 70 GS 455 rot box beater now has a Muncie M21 in it. And Ive now installed a 70 8.2 in it. The driveshaft that came out was a 55". It seems it needs a 55 1/2 which I have also. But its hard getting an accurate measurement laying under the car with my foot holding the tape measure up. I wanted to know what the factory specified just to make sure. And incredibly, I don't have a 70 assembly manual to look at the driveshaft chart (I know.. I'm so ashamed of myself!) If anyone can tell me the factory driveshaft length for a 70 GS-455 with an m21 and an 8.2 I would be grateful
Jason, Not sure if it helps but the 69 Manual is 56.00 center/center. I am thinking the 70 is a bit shorter possibly?
Good day,I just looked,56 inches is correct. Four speeds and Th350 auto cars used that length (they have different part numbers)55.1 is for turbo 400 cars Good luck. Tim
Thanks guys. 56 makes sense. Im sure the 69 is the same as 70. Im thinking Im not going to be able to get way with a 55 1/2
Some people may think that 1/2" is not a big deal,but you really do need to have all of the correct lengths. With the suspension under load,you should be able to insert the yoke all the way into the transmission,then pull it back about 1" to seat into the rear yoke. This gives proper engagement of the yoke into the trans,and also allows ample movement when the suspension travels.
Bruno came to the rescue! He had not one, but two 56" long driveshafts to choose from! I like to think I have a pretty big collection of parts, but Bruno makes me look like an amateur collector. We must of pulled out over a dozen driveshafts from his stash. He saved the day I pressed in some new U joints when I got home and it fits perfectly. I have about a 1/2" of yoke coming out past the seal.
And consider all of the parts he has liquidated to all of us in the last 10 years. His collection must have been enormous back in the day! Troy
