I couldnt find an exact match from any previous posts.

Transmission tends to shift hard (not enough to shake th truck just enough to feel it) upshifting and downshifting. from 45mph-65mph it feels like it might be slipping, seems like its going up and down a lot however when I put it in D it does the same thing (i put my foot on the gas to accelerate it feels what honestly feels like the driveshaft U joint clunk). I dont have a tach so I cant verify if or how much.

Also dont know if this is relevant but when I take my foot off the brake when in D it will get up to 15MPH without having to touch the gas pedal, so Im wondering if the torque converter is locked up as well?

Fluid level is ok, doesn't smell very burnt. I do plan on changing it and doing the filter as well but its going to be a month or 2 before I can get to it.

I'm not seeing anything odd MPG wise, with about 21 highway. I'm hoping I can at least get another few thousand miles out of it before it needs rebuilt/replaced.

 

If torque converter is locked engine will stall if you stop

15mph on level road in Drive would mean idle RPMs are too high, expected is 5-7mph, not a function of torque converter

Torque converter should be locked above 45mph so should feel more like direct drive. i.e. increased engine RPM = instant mph increase, no "slipping"

What year Ranger?

1988 and up A4LD will have a TCC(torque converter lock) solenoid which should lock the torque converter when you reach a certain MPH, about 45, this requires a functioning speedometer/VSS

If a solenoid is bad that will set a code, same for bad VSS
What codes depends on the year of the Ranger

 

Its a 1993, no codes showing up with the OBD1 reader (if they would on that).

Just wondering if there's anything to help the issues or prolong before it needs rebuilt/replaced.

Thanks again for the help Ron

 

You can add some "trans fix" fluid, any brand is fine
These additives swell seal and gasket material to reduce the loss of internal pressure
All automatics run on fluid pressure
110psi need for forward and 160psi for reverse, which is why reverse is often lost first when there is a problem with internal pressure on an automatic

The pressure holds the clutches open or closed and also holds the brakes(bands) on the planetary gears

 

Another question, will it hurt to add trans fix fluid even though the trans fluid isnt low? dont want to damage it by overfilling

 

You should probably drain some out
Loosen trans cooler line and you should drain out a pint or so, you can disable spark and crank engine over to get more out
I wouldn't start engine with line disconnected or you may get more out than you bargained for