My 1991 jeep cherokee won't shift out 4 w dr back to 2w dr can force it if I put in reverse etc can it be shift solenoid or low fluid?

Sounds like the solenoid is going out.

Sounds like maybe the filter isn't seated in the seal or the seal is missing/broken and sucking air into the pump, this would cause bubbles, one way to tell for sure is to overfill the transmission by a couple quarts for testing and see if the bubbles go away.

check your transmission fluid. They will be hard to shift, almost like it has to be "forced" when the fluid level gets too low. Just make sure the car is running and at normal operating temperature when you check it. Do not check it when it is off, or it has just been cranked. It will not be as accurate.

the nss should be at the shift lever. you have to take the plastic cover off and see the rachet for the shifter. I would check the fuse first

P0740 JEEP - Torque Converter Clutch Circuit
Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Transmission shift shock
- Vehicle may not shift into the highest gear

Possible causes
- Low transmission fluid level
- Dirty transmission fluid
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness or connectors
- Torque converter clutch solenoid valve circuit is open or shorted

When is the code detected?
Torque Converter Clutch (TCC) unlocked for 10 sec., ECM commands converter lock-up and did not record engine speed drop.

P0740 JEEP Description
The torque converter clutch solenoid valve is activated, with the gear in D4, by the Transmission Control Module (TCM) in response to signals sent from the vehicle speed and the Engine Control Module (ECM). Lock-up piston operation will then be controlled. When the torque converter clutch solenoid valve is activated, the torque converter lockup clutch will engage creating a 1 to 1 RPM ratio between the transmission input shaft and the rotational speed of the torque converter.

Lock-up operation, however, is prohibited when A/T fluid temperature is too low.

When the accelerator pedal is depressed (less than 2/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.

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Sounds like a shift solenoid. They are not too expensive and fairly easy to install. You will need to drop the pan and then you should be able to see the solenoids. But, before you do, put a scan tool on it and make certain. Good Luck

This could be an issue with the shift solenoid , but can also be caused by low fluid due to a leak, check your fluid. Is there a check engine light on, if there is it could be a solenoid issue.

YOU NEED TO GET THE REVERSE SOLENOID CHECKED BUT 99% SURE YOU NEED REBUILD

the jeep cherokee has 2 different types of 4 wd systems. the command trac has 2 wd, 4hi, neutral and 4 low. if driving on pavement make sure it's in 2 wd. it also has shift on the fly, up to 60 mph you can move the lever to 4 hi and it will not hurt anything. if trying to go to 4 low, be rolling less than 5mph and put the trans shifter in neutral and move the 4wd selector to 4 low. do the reverse to move back to 4 hi or 2 wd

IT COULD BE SOLENOID PACK OR THE GOVERNOR AND TRANSDUCER OR LOW FLUID OR THE MOST COMMON REPAIR SPEEDS SENSORS INPUT/OUTPUT. ALL OF THESE CONTROLS THE SHIFTING. START WITH THE SENSORS FIRST, VERY COMMON.