We own a 2010 Toyota Sienna Minivan. Recently one of the sliding door hinges began to fail. It turns out that this is actually quite a simple fix. Three bolts and less than an hour of work.

This is the Canadian CE model. I have no idea if the US Toyota van models differ that much, but I highly doubt it. ie: I know that Canadian models have daytime running lights. I'm not sure what other differences there might be, but I doubt that it affects the sliding doors.

One thing to note is that we have the MANUAL doors. These are not power sliding doors. The fix for power sliding doors is similar, but it requires a bit more work to remove and re-attach a cable to the sliding hinge.

NOTE: I AM NOT A MECHANIC!!! Just a DIY guy sharing his experiences.

We noticed the problem because the door became slightly difficult to close -- it required a bit more force to get it to latch. As the door opened, it would drop a small amount -- maybe a quarter inch (or 5mm) or so.

The hinge is located at the back of the sliding door, and is quite hidden, as it is always between the door and the van. It's not easy to see, but in comparing it to the other hinge, it apeared that something was working loose in the pivot assembly. (the part that attaches to the door.)

I researched this online and found the hinges on amazon. The left and right doors have the same hinge, but they are mirror images of each other, so you need to be sure that you order the correct hinge.
I have links below to BOTH types of hinges.

They are genuine Toyota parts, and pretty solid and well constructed. Howerver they arrive as bare metal. I cleaned them with some alcohol and then sprayed on some rust paint. I picked red, to try and match the body colour of the car, at least a little bit. (Turned out I got a much brighter shade of red, but oh well, it's mostly hidden.)

I left the paint to harden for at least 24 hours before installing.

The hinge is the only thing holding up the back of the door. So I wedged a crate and some scrap wood under the partially open door for support. This is to prevent the door from dropping once I detach the old hinge.

Here is a closeup of the new hinge. There are just three bolts that attach it to the door. On the other side, there are three roller bearings which fit into the sliding track on the side of the van body.

Note that power sliding doors have a cable assembly that also attaches to the hinge for pulling the door front and back.

Also note that the bolt holes are slightly enlarged, which allows a bit of wiggle room to adjust the door up or down to get it into the correct position to latch well.

This photo is actually of installing the new hinge... It was very tight quarters, so I don't really have a good close video of the removal. I used a wrench to remove the three bolts that hold the hinge to the door.

Once the hinge is detached you can swing the door a bit away from the van to give yourself a bit more room to remove the old hinge and then fit in the new one.

Once the bolts have been removed, I slid the hinge to the front of the track. This photo is a bit distored due to it being a wide-angle lens at close range -- there is a bit of a fisheye affect. On the left you see the interior of the van. On the right is the slidding door. I'm holding the old hinge. After sliding it to the front of the track I can tilt it up and then the roller bearing wheels just lift out of the sliding track.

To install the new hinge, just reverse the procedure. I first slipped the new hinge into the track, then slid it along to line up with the back of the door. Then I re-installed the three bolts. I found that I needed lift the door slightly when tightening the bolts, in order to get the door into it's best position. There is a V-shaped opening on the door, which latches to a catch on the frame. The two need to be positioned to line up, in order for the door to latch easily. (It will still latch if it is slightly mis-aligned, but we don't want to have to fight the door!)

This was a quick and easy fix. Even with filming the process it took me less than an hour.