The saame thing happend to me on both back doors so I just kicked out the back doors ( make sure you have the handle open if you do) it was just rusted up then open the door panel and take out the bottom latch and now i have to just order the new latches

 

My driver quad door was stuck. I would have to pull the handle and yank on the door to open. I lubed everything and it did not help. I took the door panel off and realized the rod that opens the lower latch has slipped. I adjusted the rod length and it works perfectly. The door would also not open from the inside latch because the cable that it operated broke off at the door side of the cable. So the fix is to adjust the rod length and the door will open. But of course you need the door open to take the panel off to get to the rod.

 

Actually the panel will come off without opening the door. Just be cautious. Another way to get at the rod(s) is to go through the outer handle cutout. Undo the two Torx fasteners and work the handle out carefully. The cable for the inner handle pops off easily. I used a telescopic magnet to retrieve the rod, which is all I needed to do for the driver's side.
I'm to Sea-Foam step now for the passenger side; latch is seized right up. Lacking success with Sea-Foam will do the Dremel method. I didn't like the idea of trying to sawzall the pin. There's plenty of room to get a Dremel in there but not so much with a sawzall between the latch and the pin.

 

98 Ram 2500 ext cab 4x4
240k

I have the same issue with the extended cab doors; worked on it today here is what I found:
1.) door stuck - a block of wood and a mallet while holding the door handle with some force to open the door be careful to not bust your plastics
2.) remove inner door panel
3.) remove vent
4.) lube nuts inside door (get your 10mm ready)
5.) remove the 3 nuts (use your torx on the bottom if they spin)
6.) there is a gasket between the latch assembly and the bottom of the door, smack the assembly from inside the door cavity to break it free
7.) replace the assembly because these things suck

I took the assembly apart because I can fab most items in my shop, but these are just garbage. They have a coating on them to prevent corrosion that epically fails and causes the issue. The lock lever is froze solid due to the pivots being made from nylon. Once the nylon wears out its metal on metal seizure. Also to note the (3) bolts have blue thread locker on them (especially fun to remove) one bolt is the pivot for the lock mechanism; one bolt is the fulcrum for the actual latch; the last bolt helps hold the assembly together. Once removed you have to drill the grommets in each bolt hole to remove the cover. Allot of crap fell out. Heres a link to the pic, hope it helps:

http://www.flickr.com/photos/1275873...7628165023689/

One pic has explicit details


As far as the door pin attached to the rocker panel, I simply sand blasted and repainted - its good as new.
Now to source the latch

I just called the dealer the freakin latch is $97.57 - holy crap

 

Good post, Bigaaron...
My problem was getting the latch to release the pin. It was THAT seized. had to cut the bolts from inside the door with a Dremel and pursuade the door up over the latch, which stayed there after I pried the door over it. From there I had to destroy the latch to get it off the pin.
Pain in the butt that was but got it done without too much damage to the door.
Word of advice to anyone else with this problem, check the latch rods inside the door before assuming that holding the latch handle open actually is operating the latch release. Mine wasn't and I almost totally trashed the door with the wood and hammer method. Both rear doors on my truck had disconnected latch rods.

-m

 

I just called the dealer the freakin latch is $97.57 - holy crap

if anyone has a source other than a junkyard let me know. If not, I will fix this terd.

 

I was able to free mine using a dead blow hammer and holding the door handle in the open position. Took lots of WD40 and elbow grease but it came open. Once I got it open I used air to blow it out really good then a hammer and large punch while laying on the ground underneath it to cycle it about 20 or 30 times. Once I got the latch to cycle properly I blew it out again and sprayed it liberally with more WD40 to ensure it doesn't happen again. been going strong for over a year now. Just remove the inner plastic before you start beating the door with the hammer.

 

WD-40 only lasts so long, hit it with some rust penetrant, and make sure it is cleaned out nice, then spray in some white lithium grease. Should last forever.

 

+1 on the white lithium. Works great, keeps dirt out of latch better than WD 40, which attracts dirt and does not keet it out. Manufacturers actually use white klithium on latches (or did).

 

Guys, I apologize if this is too late for this thread.
I had the same issue, but no rust. It appeared that the top latch would 'unlock' or at least release but the bottom would not. The door would be tough to open, I greased it, WD'd it, and had that bottom latch working like new, Still wouldn't open easily. Seems that where the two rods meet in the middle of the door, there is a fulcrum type assembly where both rods pivot. Well, the bolt that holds this pivot point (or fulcrum) in place, at least on mine, had almost fallen out. The second it was tightened up that 8mm bolt (almost 3 full turns), the cargo door works as good as new!, everytime!