transmition to carb linkage?

[oranjeff]

I have an 78 chevy shortbed with a 350 engine and 350 trans. I was on the highway when it shifted down and stayed there. The only way I can get it to shift back up is to quickly push the gas a couple of times. But it shifts right back down a few seconds. Could this be caused by a linkage malfunction going to the carb or is it a problem with the transmission itself? Any help would be great.
Thanks.

[Lt.Del]

It could be fluid level.  It could be transmission bands.  and, it could be the kickdown cable. 

If it is the kickdown cable, pull the tab up on the cable by the carb....adjust it with lots of slack to rule it out, in other words, ensure it isn't too tight.




or take the whole thing out to rule it out....just joking, don't have to do that.  These are pics when I removed my engine years ago...so i knew how everything went back together.



 

[VileZambonie]

Unless the detent cable is stuck pop the cover off the governor housing. Pull the governor out and check to see if the gear is apple cored.