Doors where you have to remove the lower frame section.
Great video on removing the lower frame section. I need to do this on some sliding doors I have. I was wondering if you could show a video of replacing the frame section after the roller and carriage has been replaced. I wonder of the difficulty of getting the spline and glass and frame back together.
As an alternative method for these type of doors I was wondering if using a Dremel tool or something to cut the grooves in the lower frame section that hold the carriages in. I would do it in the middle of the lower frame, then slide the old carriages along there and pull them out and pop the new ones in and then slide them along into place at the ends.
Looking at your photos, I can see that your lower frame is held together with screws on the end. One screw is for the wheel adjustment and the other is for securing the frame together.
You will need to lay the door down on a work table or a set of saw horses (make sure that whatever surface you use can hold the weight of the door). Remove the corner wheel which holds the frame together. To remove the bottom rail, I recommend using a block of wood and a hammer or mallet. With the block of wood on the top edge of the rail, slowly and carefully tap off the rail.
With the bottom rail removed you should be able to access the roller. If you are not sure you want to deal with the trouble, it's best to get someone who is familiar with patio door repairs to come out and look at it for you. This can be a bit of a project.