I just checked mine and it seems tight.
I will say I am dissapointed in this issue Toyota has.
Their fix is okay.

After driving 4 miles, passenger side popped.
Very unfortunate. I am trying to like this car, but with OCD on repairs etc, its rubbing me raw.
The two tabs that lock into the bracket just have very little bite. On the side of the bumper towards the tire, it bites hard. You feel it when you pull bumper off.
Its flexible plastic, and flexes it does.
If this was metal, or much more rigid, and the bumper teeth that go in were more of a lockable design, I wouldnt be having this issue.
So, conclusion, if yours ever pops due to damage, (Mine apparently was), then sell it.. If you care about the looks..

Well, The TSB to "secure" the bumper better just doesnt do well. The parts that are secured to the bumper are secured better than the bumper to the cars fenders etc.
I think the mold keeps a certain tension once product is finished, and, it just pops out due to tension and weak little finger nail clips to bracket. Bracket is weak do, very easy to flex it where the clips go in..
I am done with it. Just going to accept poor design on the bumper and live with it. Teach my grand kids to lightly push it back in every time we park.

Can these brackets be ordered online, or is it a dealer only part?

Yes, they can be ordered online, but the ultimate ripoff is the "garnish set" which is alcohol prep pads, adhesion promoter pads and Velcro... and is supposed to contain two washer/spacers. If you look at the new supports, the place where the cover is captured inside the fender well is taller than the old style support and the washer looks to close the gap so the bumper cover will capture properly when the screw is tightened. I ended up buying the Velcro and adhesion promoter from Amazon and 3D printed the "washers" out of poly carbonate.



All of that said, I was not impressed with the TSB. Does it capture the portion of the bumper cover under the headlight? Yes it does. But, the stack up of the Velcro causes the sides to bulge out. After about two weeks of looking at the mess, I ended up pulling the cover off again, and used the smaller attachment points (circled in green) at the top of the bracket and removed the larger Velcro pads below. It works and looks better for me, YMMV.

As previously stated, the whole thing is kind of half a$$. If I were doing this again (before spending $100+ on brackets, Velcro, etc.) I'd try to find high end waterproof two way tape (something like 3M VHB) and use with the existing brackets, applying the tape in the area circled in yellow. I have a suspicion if you use the adhesion promoter with the two-way tape in this area the problem might be solved without the modified brackets. Again, YMMV.



New part numbers:

52115-35153 - Support, Front Bumper Side, RH
52116-35153 - Support, Front Bumper Side, LH
67069-35010 - Garnish Set

I just bought the brackets at the dealer, while my wife was chatting with a guy about new 4Runners (4 to 6 months, will sell at MSRP except for special colors like Luna Rock which she wants and an Off Road Pro). The garnish kit was $89 while the brackets were $48 each. So just got the brackets and found the velcro for $12.99 and Adhesion primer for $17 on Amazon. The 4Runner needs a new driver's side inner fender well as it has broken tabs around lower, outer front screws and rubbed on the tire. These are very flimsy.

I am curious how the washers affect the install?
Is the Limited bumper acting different with this washer?
I cant see what it does... I did no measurements before installing..

Not sure. The only thing I can come up with is possibly pulling the cover a little tighter against the bracket?

Hmm, I need to loosen mine a little and then slowly tighten to see if it moves.
The Limited Bumper is a easily moved bumper.
I pushed where it is locked in under the headlight, and I saw the outer side where its popping out move.

Hmm, didnt do anything.. Or maybe I cant see any movement.

Someone posted somewhere in the forums, that maybe the fender area needs to be pulled out a little. If you look in post 5, there is a pic of the fender, with bumper gone. The wavy section of the fender hidden by the bumper may need to be pulled out. If you look at this other picture I just took, the drivers side is in a little and tucked under the headlight just also a bit, I think. Need to look at other 4runners.
But, its a thought as the passenger side of mine was pushed in a bit, and I can see it. I need to see if I can pull it out a bit.
This pic shows how the fender is in further than the bumper, and under the headlight where the little blue lines are, its a but tucked under.

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Bumper came off before I even went down the street. Velcro did not work.
I either need a new bumper or it needs to be super epoxied on.. What a POS.

Well, went a little redneck on it and fixed it, well made it stay till I can honestly evaluate the fix. Probably a new bumper and such.
I went and put a temporary zip tie into a bracket near the windshield washer fluid. Its a metal one. And, the other end of the zip tie went into the bumper, chrome section of the limited, that attached to the cover. I took its clip out and ran the zip tie through it. Then, lightly pushed on bumper cover and sinched the zip tie.
Then went on a very bumpy ride for 20 plus miles. Bumper stayed..
Its a temp fix, but it is holding so far.
I am fairly certain the passenger side fender front needs to be bent out a little after it was hit and it will allow the bumper to hold in place.

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Do you have the dimensions of the washers?

Just an update, after 6 months , bumper has not moved. Zip ties seem to be working for my limited, to keep bumper in position it came from the factory.