98 Durango will not turn over, replaced battery, battery cables, had started checked. Just get a clicking noise at starter like a dead battery. Will start some times.

Sounds like a bad connection. Clean all the connections first then if you have a clicking sound coming from the PDC (fuse box) on the drivers side under the hood then it sounds like you have a bad starter .
As the relay is clicking that means the ignition switch is good. Just insure that the relay is good. There is a spare in the PDC you can swap and check out so its the starter Starter/solenoid combo.take your volt meter and check battery volts while the starter is engaged, if you see very little change from the static voltage it's likely the starter bendix is being egaged into the ring gear but the high current side of the starter is not working, this is likely due to a dirty or worn commutator or worn brushes in the starter motor. If you do see a larger drop in voltage( say down to under 9.5volts) you more than likely have a current flow issue, possibly a weak cell in the battery, or a shorted starter motor winding.My best recomendation would be to remove the starter motor, and the battery, take them in with you to your local parts house and have them both tested, most parts stores will perform these tests for free, on the possibility that hey can sell you something.
STARTER MOTORREMOVAL:-1. Disconnect and isolate the battery negative cable.2. Raise and support the vehicle.3. Remove the nut and lock washer securing the starter motor to the mounting stud on the transmission torque converter housing Starter Motor Remove/Install4. While supporting the starter motor with one hand, use the other hand to remove the upper mounting screw from the starter motor.5. Slide the automatic transmission cooler tube bracket forward on the tubes far enough for the starter motor mounting flange to be removed from the lower mounting stud.6. Move the starter motor towards the front of the vehicle far enough for the nose of the starter pinion housing to clear the transmission torque converter housing. Always support the starter motor during this process, do not let the starter motor hang from the wire harness.7. Tilt the nose downwards and lower the starter motor far enough to access and remove the nut that secures the battery positive cable connector eyelet to the solenoid battery terminal stud. Always support the starter motor during this process, do not let the starter motor hang from the wire harness.8. Remove the battery positive cable connector eyelet from the solenoid battery terminal stud. Always support the starter motor during this process, do not let the starter motor hang from the wire harness.9. Disconnect the battery positive cable wire harness connector from the solenoid terminal connector receptacle. Always support the starter motor during this process, do not let the starter motor hang from the wire harness.10.Remove the starter motor from the engine compartment. --This will help. Thanks please keep updated.please do rate the solution positively .thank you for using fixya

This is typically a bad starter relay - or corroded wire/terminals.

Thanks!