Remove the door sand and seal it with primer or polyurethane on the top and bottom edges.
How to fix a warped sliding door.
I would replace the door because that s the easiest solution but if you have more patience than i do here are tips for flattening a warped door.
Place a pencil between the doorjamb and the door in the location of where the door is striking the doorjamb first.
Place the heavy objects at the center of the crown of the warp.
Leave the pencil in place for 30 minutes.
Straightening the track could be the most difficult.
If the door has begun to straighten but is still slightly warped you will want to repeat the pencil in the door method.
Once choice is to use moisture to reverse the effects of the warp.
There are replacement tracks has to match the old one that will now lay in the slot.
For a slightly bowed door take a heavy weight and lay.
Determine where the crown the highest point of the warp is mark it and flip the wood over so that the crown is on the ground.
Let the door remain this way.
You then use a die grinder burr to smooth the surface.
You have a few options for straightening out warped wood.
Two sawhorses screwdriver sandpaper heavy towels or a large blanket varnish paintbrush 50 lb sandbag or something of equal weight.
Take the pencil out to see if the door has started to straighten.
To me a warped frame means twisted.
Basically you take a rivet buster chisel and die grinder and remove the track.
What you need to fix a warped wooden door.