Automatic shifts to soon

[Lostcause]

Hello everyone, I have a 91 mustang GT automatic. My problem is when I leave the car in drive and floor it first gear shifts at about 3100 RPM's, second gear not even that high shifts right away into third. If I manually shift the car using the 1-2-1 method it holds on to the gears all the way through. Any help for fixing this problem will be greatly appriciated. Thank you all in advance.

 

[mikestang63]

check your TV cable. A misadjusted cable can fry a transmission in a very short time. Make sure the plastic bushing is not broken. I would recommend replacing it with a brass bushing and clip. If you are not comfortable with this take it to a transmission shop where they can adjust it by the pressure.

Here is a video for reference.




By the way, the easiest way to burn out an AOD is to do the 1-2-1 shuffle.

 

[werner]

Would a c4 be adjusted the same way ?

 

[88LX5.Oh]

Would a c4 be adjusted the same way ?

C4 doesn't have a throttle pressure set up like the AOD. C4 has an internal governor that uses the centrifugal force of the output shaft spinning to dictate line pressure/shift points.

 

[ratio411]

Would a c4 be adjusted the same way ?

The c4 decides on it's shift points through 2 ajustable inputs.

One is the modulator valve, which is vacuum operated, and is adjusted with a tiny flat tip screwdriver in the vacuum nipple.
The other is a primative form of the TV cable, which is called a "passing gear" or "kickdown" arm.
You can adjust the arm to set your desired downshift point, and it also acts to keep the tranny in it's gears longer when you are driving aggressively. If you are driving easy, the kickdown is not operated, and the tranny shifts to your modulator adjustment.

Not to mention that the c4 has individual detents for each gear, so it can be manually shifted as well without trickery.

 

[88LX5.Oh]

C4 doesn't have a throttle pressure set up like the AOD. C4 has an internal governor that uses the centrifugal force of the output shaft spinning to dictate line pressure/shift points.

Since I don't like to give out incomplete/wrong information, I might want to add that the AOD ALSO has a governor setup, but it used in conjunction with the TV set up. And Ratio basically covered all the rest lol

 

[MFE92]

It's usually because the $2 grommet that attaches the cable to the throttle arm is broken and missing.