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seems to be a common issue

1K views 15 replies 8 participants last post by  Bbrown258 
#1 ·
My freshly rebuilt C4 Trans does not take off in 1st. It always takes off in 2nd. I can goose it and it down shifts and if I take off right away it will stay in 1st and operate normally. However if I hesitate after I goose it it's shifts right back up into 2nd and goes from there. My kick down is adjusted properly. And my 2-3 shift operates normally up shifting and downshifting. Even if I shift into neutral and back to drive. Still stays in 2nd. If I drop into 1 and back to drive it drops...any help would be awesome.
 
#5 ·
You also might want to check if the rod in the vacuum modulator tube is the correct length... or may have fallen out. The rod length (and I believe there are 4 options) will determine the rpm where the tranny shifts.
 
#9 ·
If it is a 65/66 transmission, the position you consider "Drive" actually starts in 2nd and shifts to 3rd. The correct "drive" position is where you would consider 2nd gear to be.

With all that said, if it is not a 65/66 transmission, then I have no idea.
 
#14 · (Edited)
Update. I tested car in "1" and it hold's in 1st gear forever. Tested in "2" holds in 2 forever. And in D I get 2-3 shift. Looks like I will be draining my trans and pulling valve body to take apart and clean


Also. If I pull extension housing with trans full how much will drain out? My thought processes is pull valve body. Clean and reinstall. Test drive. Then if problem persists tackle Gouverneur assembly
 
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