Mitsubishi: 91 galant transmission problem, cottman transmissions, salvage yard

Question
i had kenndy replace the first one with a rebuilt
i got my back and two others from a salvage yard
friend installed other but they all do the same
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-----Question-----
hey i have a problem with my galant i have replace three
trans it seems be only stuck in 3rd gear i have tried to down shift 2,l it is the same when i am drive i also replace my my computer and still the same is there a sensor that i need to replace
-----Answer-----
Hi Mike,

Who is replacing these transmissions and are you having used ones installed?

Answer
Hi Mike,

Wow, Kennedy is supposed to have a good rep, but I think this is a bad sensor. There is likely a check engine light on on the dash and this will indicate the bad sensor. Some sensors on earlier models won't turn on the CEL but stores a code in the computer anyway. I suggest you take it to an expert like Cottman transmissions or Aamco. They will diagnose this for free. Expect a bad sensor and the repair should be under $200.