i have a 1992 toyota pick up. Two wheel drive automatic.When you drive it you have to shift it manually. When you come to a red light and you stop it will not shift down. so therefore you have to shift by hand. The transmission seems to work fine. No slipping or anything like that.Does the transmission have a selenoid or relay that could be bad or what is it?
It has a modulator which controls the shift both up and down. You need to see a good transmission mechanic to get your “automatic” back.
Cant really give you a solid answer since I dont know what pickup you have. Is it a T-100, a Tacoma??? What size engine in it?? There are many different transmissions used in the Toyota P/U’s. What you’re describing sounds like a sticking governor especially since you said that the trans will not downshift after stopping and you have to manually down shift it. Give me some more info on the truck so I can give you a more accurate answer.