1988 chevy TH375

Hi. Im working on a 1988 chevy c1500 305 (remanufactured)engine put in a TH375 Trans(remanufactuerd) . When I plug in the (Orange)wire for the passing gear the tranny seems to slip out of gear. now with the wire unplugged tranny dont slip but then I have no passing gear. Is this a tranny problem or electrical ?


note : already replaced the solinoid

Are you sure you have a 375 and not a 475? I thought the 375 was only used in smaller cars.
And why didn't you just go with a standard TH400? Is this a special use or something?

Are you sure you have a 375 and not a 475? I thought the 375 was only used in smaller cars.
And why didn't you just go with a standard TH400? Is this a special use or something?


you would be surprised what they stick in cars n trucks today. All a TH375 is its a 350 with a 400 spline basically a beffed up 350

ok, i'm confused, when did any 350 have electronic kickdown? does sound like a 475 to me.

In 1987 they started the electronic kickdown.
TH375C 9" Tail w/smll output shaft