I have a 2000 Durango. Started having problems where the lift gate wouldn't close - had to always do it twice. Now the door is closed, but won't unlock and open.

How can I get the lift gate unlocked?

 

Try pushing on the hatch while trying to unlock it (worked on a friend of mines Explorer), if that doesnt work crawl in the back and see if you can remove the hatch panel and unlock it that way.

 

When you do get it open you need to fix the handle but as stated before it may need to be popped open by removing the hatch paneling off first.

 

I've had this problem and I am on my second door.

The latch gets sticky, especially if you've had rust treatment and that material has gotten into the lock mechanism.

I used WD40 to clean the lock mechanism but then I removed the WD40 and replaced it with Gun Treatment Oil. Use the WD40 to clean and displace moisture but don't confuse WD40 with lubricant. Once its clean, use a proper lubricant for long term use - I've seen lithium greased used quite often.

After that it was still a tad sticky, but much more workable.