1989 Nissan 240sx Recued from the Grave! Tranny shifting at 5500-6400 in all gears! Why?


#1

Hi, folks.

I bought this car off of a friend, who has had the car parked for 4 years because of this problem. It was cheap, and the car is in perfect condition outside, and 95% perfect inside. So I am hoping to fix it for cheap. It only has 151K mile on the tranny, and the other driver put 30,000 miles on it in the condition it is in now. He said it wont shift into overdrive, but I guess he was just scared to tach. it up to 6500 in 3rd gear. Once it shifts into overdrive, and all other gears, it runs fine in gear. It downshifts correctly, and even under maximum throttle, it does it's job right. It just will not upshift until the above listed RPM ranges I already changed the trans fluid and filter. The trans gets so hot under this driving condition, that it is putting a lot of heat back into the motor coolant, which I believe is deteriorating the head gasket, because now the radiator is foaming, and consuming coolant/water.

Please help.


#2

Check the “kickdown” cable/linkage that goes from the throttle to the trans.


#3

The transmission cooler in the radiator may have failed which would let trans fluid into the radiator and coolant into the transmission.