98 dodge 1500 5.2 1st gear is shifting to soon. Was advised to adjust throtle cable but can't set it right. Is there a proper way to do this or could it be a stretched cable or solenoid? How do I figure it out where the problem is?

 

Welcome to DF
The way to adjust the throttle cable (TV), is remove the cable from the throttle and with the throttle closed. Does the black connector you removed from the throttle even with the pin you removed it from? If its not, then adjust the cable until it is even and then install the cable back on.

 

Not sure what you mean about the black connector even with the pin I removed. Do you have a diagram? I know the parts your talking about but not sure your instructions.
Was told that if a solenoid is stuck, there's a solution to pour in the transmission to free it up?
Rick