I have a 4L60E that i just rebuilt and am having some problems with it! I am not a genius per say but i have built my share of these tranmissions too! If you get in truck to go and put it in first gear it will go in first gear and go 1st to 2nd to third but will never go in to 4th and rpm's fall when it is trying to go in fourth if you let your foot off of the accel. If you start descending gears down it will never go back into 1st gear again. If you even come to a stop it starts out in second gear! Now, if you turn truck off for 10 seconds and restart it will start out in 1st gear again and go through but still has no fourth! What have i missed! I have had the VB back down on it and made sure valves are not stuck and so on! Thanks to all in advance as i am new to this site!!
Is it possible that it is going into limp mode after the first cycle of shifts and if so what causes limp mode generally speaking?? will the trans. pressure switch cause this??? Thanks

 

I answered your other post about this. You should get this thing scanned to check for codes.

Frank
CPT