Hey guys here a issue we been working on for bout a week now i got a 99 gmc sierra z71 full bolt ons etc its got fully built tranny new clutches servo shell band build valve body with shift kit 3200 circle d converter heres the issue truck ran great went in shop pulled top end apart just headers manifold heads p&p valve job put bak together fired right up hadent touched pcm or tranny and all it goes in first fine but basically no 2nd shifts really slow its like main line pressure is low replaced tps it was good we have every gear cept 2 and no converter lock up anyone got a clue?

 

David if I read your post correctly the trans was working fine before the work being performed to the engine. Since then you now do not have second gear or lu. All other gears seem fine? Have you had your truck scanned for codes?

 

yes ive had hp tuner on it for two days now for about 12 hours total no codes..sucks lol ive heard look at tps and map pulled tps of a trans am and tryed it no difference it sat on dyno alday today and couldnt get it to hold in second i will floor it in second and it will smack limiter and no increase in tranny temp the tranny itself was extremly stout before everything got put bak together correctly this is like my third build on one of there setups nd never seem anything like it

 

im going to check the map sensor tomorrow if that aint it ill trully be stumped

 

There are two things I would do here. One would be to put a pressure gauge on the trans and look at what the pressure is doing especially in second gear. The other would be to look at transmission data to verify that the "A" solenoid is being commanded to shut off for the 1-2 shift. The A solenoid might also be referred to the 1-2 Sol depending on what you are using. I would think that with the trans slipping in second gear you should be getting some kind of code. How does the trans work if you are easy on the throttle on the road?

 

lite on throttle it works fine no slippage at all in second theres nothin and tranny temp doesnt rise so i doubt slippage if i hammer it in second it will grab around 5k alomst like it was increase mainline pressure until a extreme amount of load is put on today pulled servo that lookd and sealed up great and then droped pan and pulled 1-2 accmulater that looks great and sealed up also i got a older uy coming in later to look and this roads getting thiner and thinner

 

were pulling the trans out somtime soon ill let yall know what we find out