hi guys,

i'm a new guy that's having an issue with a 700r4 in an 89 gmc pick up. i know it's not an F body, but i figured you'd guys would be more knowledgeable about my situation than some random truck forum.

okay, we put a new 350 engine in this guy's truck. truck runs great, but now there is some transmission issue. the cooler inside the radiator was leaking and some coolant got inside of the transmission. pump was working great initially when coolant problem was discovered. fixed the issue, drained the fluid out by dropping the pan, installed a new filter and gasket, poured in new fluid, and went on to disconnect the cooler return line to try and pump out any contaminated fluid that was still in the converter/lines while pouring in more new fluid at the same time to keep it from running dry. the only problem is, there is hardly any fluid pumping through the lines. it's just dripping out. we went through all the gears, and discovered that the transmission won't shift from 1-2 unless i let off the gas, the rest of the gears shift fine. i would think that if the pump was bad, it would not shift at all. i'm a little stumped on the issue. what do you guys think?

thanks a lot for your help

 

Maybe the 1-2 accumulaor spring is broken

 

i'll check it out. thanks for the help