Good job finding it! That's one of the first things that came to mind when you described it...but I have never actually heard of it happening before.
Hunting between 1st and 2nd. My C-4 has an annoying habit of hunting between 1st and 2nd gear when my speed is just at the shift point between 1st and 2nd. In other words, when I'm going 5mph in a traffic jam (and it would shift at some point between 5 and 6mph), it'll oscillate between 1st and 2nd unless I either slow down below the shift point or give it a little more gas to force the issue. Any suggestions what would cause this? It otherwise works fine. Joe
first make sure your fluid levels are good. if so its probably needing some band adjustment. if you know how to adjust the bands then feel free. they are adjusted by bolts on the side of the tranny. if you dont know though i would suggest paying a good trans shop to adjust them.
I'm not sure, but maybe it is the vacuum modulator that needs adjustment or has a vacuum leak?? Does it slip in and out of the 2 gears or just back and forth? It could also be your transmission is just getting tired and needs a rebuild after all those miles. Getting the tranny to shift properly in drive is more complicated and beyond my experience because I have only dealt with the manual valve body, which doesn't use the kickdown, modulator and other things that could cause problems. I think the modulator and fluid pressures have to be just right to get it to shift properly. I'm sure if you post a new thread in the Technical section the experts on here will be able to help you out.
I was gonna rebuild the C4 behind my 250 when I installed a new rebuilt 250. Several weeks ago I put in a new modulator because the original was shot. Tranny seems to be great now ... I figure that since it was only behind a 250 6-banger and driven by a 55 - 85 year old lady it's entire life and has 95,000 miles on it that the tranny should be fine for quite a while longer. I've decided not to get it rebuilt when I do my engine swap.
