okay, finally got the 350 in my 86. ran BEAUTIFULLY. then i drove iton the highway. it wouldn't shift out of third gear. now itwont get out of 2nd. i get up to 25mph and then its all rev's. checking fluid, its topped off. anyone got ideas? wondering if it might be because the engine is from a 77 truck, and a lot of the electrical stuff isnt hooked up (like gauges, cruise. etc). all i could find in seach was **** on new gen blazers, nothing for the big boys.

 

What year is the transmission? What model transmission, 4L60, 700R4, TH450?

 

sorry, cant believe i forgot to mention it. its a 700r4 in an 86. the truck has over 200000 on it, no clue if the filter and fluid have ever been changed, or the tranny rebuilt. im guessing its gonna need a rebuild here.

 

me and my dad were talking, and he thinks maybe its an electrical problem. is the tranny triggered to shift electronically? he thinks since that since the egine is such a late model (77) and evertying is mechanical instead of electric (had to buy all new gauges for it) that the tranny isnt getting the heads up to shift. its still goingno further then 2nd, and slipping out of gear after 25 mph and then back in at 23. it was all working fine on the test drive, i was doing 45. but since then, its been 25.

 

stillhaving problems. i can drive just fine with the tranny in 2nd gear. but if i shift into drive or overdrive, it will just actlike its in neutral until the speed falls topoint it would shift into second. thought it might have been a pressure module popped out, but, there is nothing in the pan. might it be something electronic? its 700r4, not 4l60, but could therestill be an electrical componet screwing me?