[a-ortiz74]

have a 350 im guessing a turbo transmission. heres my question, is there a lock up plug that i need to reconnect so my transmission will work right? see when im driving and i get up to third gear its not running like it has overdrive so when i let off the gas it starts switching down gears like a manual transmission. is it the lock up switch?

[cobalt327]

Originally Posted by a-ortiz74

have a 350 im guessing a turbo transmission. heres my question, is there a lock up plug that i need to reconnect so my transmission will work right? see when im driving and i get up to third gear its not running like it has overdrive so when i let off the gas it starts switching down gears like a manual transmission. is it the lock up switch?

The TH350C has a lock up torque converter (aka "TCC"). It is operated by an electrical plug adjacent to the shift linkage, driver side.

The trans will work normally in every respect w/o the TCC lock up operational- w/the exception of a slightly higher torque converter stall speed.

I'm not sure I completely understand your symptoms, you might try explaining the problems you're having one more time.

[a-ortiz74]

well im not real sure but my truck will switch all gears but as soon as i let of the gas it starts slowing down real fast switching gears down. is that normal if my lock up is not hooked up? see i had a 82 chevy i pulled this engine from and put in a 75 chevy but i didnt see a lock up on the 75 so i left it unplugged.needless to say i didnt even get the harness because i thought it was a speedometer wire.

[tnsmith10]

Originally Posted by a-ortiz74

well im not real sure but my truck will switch all gears but as soon as i let of the gas it starts slowing down real fast switching gears down. is that normal if my lock up is not hooked up? see i had a 82 chevy i pulled this engine from and put in a 75 chevy but i didnt see a lock up on the 75 so i left it unplugged.needless to say i didnt even get the harness because i thought it was a speedometer wire.

that plug has nothing to do with the trans down shifting when you let off of the gas. either you have the detent/kick down cable set too tight or the cable is frayed and is stuck inside the cable housing.
check the adjustment on the cable and make sure its not set to tight. also while your at it, pull the cable at where it hooks up to the carb and make sure it slides in and out freely.
you dont mention how the upshifts are, are they late and firm by chance?