89 auto s10 blazer wont shift

I have an 89 auto transmission s10 blazer. A few weeks ago i started having problems with the shifting. In the morning when it was cold, it didnt want to shift but eventually would. Now, it wont shift out of 2nd. I have to stay in 2l pretty much. What r the chances of the filter needing to be changed? I was also told to check the vacuum hose, but for that tranny, its not showing anything about a vacuum modulator in the repair book

I have an 89 auto transmission s10 blazer. A few weeks ago i started having problems with the shifting. In the morning when it was cold, it didnt want to shift but eventually would. Now, it wont shift out of 2nd. I have to stay in 2l pretty much. What r the chances of the filter needing to be changed? I was also told to check the vacuum hose, but for that tranny, its not showing anything about a vacuum modulator in the repair book

No modulator valve on that one.

Is engine running good and fluid level good engine running hot?

Is the TV cable from Throttle body linkage to transmission hooked up and working and adjusted good?
Does it have a good double tension on it?

If all of that is good pull governor and check plastic gear on in and inside valve for being free movement.

Post back what you find there.

The engine and temp are normal. The TV cable is also fine. The filter is being changed now, and it was unbelievably bad. The fluid was burnt. Going to check governor also.

Well drive and over drive r pretty much out. New filter helped shifting from 1-2, but thats it

Any slippage?
Is 1 and 2 solid?
Good reverse?

What is the up-shift speed on 1-2 shift?
Have you checked governor?