I have an 87 firebird with the 2.8 mpfi and automatic trans i swapped the motor and put another 2.8 in from the same year car but now my transmission wont go into third once you hit 30 its like it slips into neutral is my tranny shot or is it somthing stupid? It has fluid in it that looks fine. The trans worked before i pulled motor. I also put a hypertech chip in if that makes a difference. I dont know what to do. Any suggestions would be helpful THanks.

 

i'm guessing it's a 700r4. did you hook the t.v. cable up properly? it will affect shifts.
One of the most common failure points of the 700r4 is the 3-4 clutches. if they are burnt or too loose they will give the symptom you describe. 1 to 2 shift is good and third the engine just revvs. doh

 

So what do i do. Do i swap the tranny now or can i mess with it without taking it out? By tv cable are talking about the kick down cable that goes to the throttle.

 

On the 700R4 it is not a kick down cable. A Th350 can be run without this cable hooked up....not the 700R4. On the 700 the cable controls the line presure of the transmission. Running with it unhooked or adjusted incorrectly is a quick way to burn up the tranmission.

 

How do i adjust the tv cable

 

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