Cadillac Transmission.

[Jason15036]

I have had my Caddy for about 5 years and probaly a year ago I got the service engine soon light coming on. It was activated by code p039 Torque converter clutch. I drove around with it and it never hurt anything. About a week ago I got code p056 input speed sensor. It still shifted fine though. Now all the sudden today im driving and it shifts fine through 1 and 2 but it wont stay in 4th gear. Its like it shifts around all the time. Now it wont stay in 3rd all the time it will shift back and forth to 2 3 4. Help, what is wrong and what should I do. I was also wondering if you could pull the Transmission without pulling the motor and is it complicated. Should I buy a new trans or should I try to fix all the problems on mine. Any help would be appreciated.

[MAC]

I have the same P039 code, but so far all I notice is slow shifts and slipping. From what I have read, it is better to buy a rebuilt transmission because the rebuild will (or at least should) incorporate upgrades. If you buy a brand new one you might have the same problems all over again. If you have the money and plan on keeping your STS you may want to consider a performance trans. http://www.domesticperformance.com

[rmac-etc]

I have had the input speed sensor codes for a long time. What you described happened to me also at about 130k and it turned out to be the shift solenoids. They are 60-70 bucks for the pair and its a messy job but do-able if you are mechanically ept. There are codes for the shift solenoids, but I never got them. Maybe the input sensor codes override something. Anyway, for 70 bucks and a couple hours of your time you may save a bunch.

This link has a good description of the procedure, scroll down to Willy Hank:

http://caddyinfo.ipbhost.com/index.php?sho...0solenoid&st=15

This link is a useful diagram of where the little steel balls go (provided by Barry94):

http://temp.corvetteforum.net/c3/a70lt1//more_balls.jpg