Bumping this up because I have the same issue on a certified pre-owned 2014 Limited that I got less than a month ago. Spoke with the salesman, and was told that the Texas heat causes the separation. (Bunch of BS, I know). He said their body guy would essentially just glue the bumper, but we would have the chance of it ripping paint off if it came separated again. Debating on taking it up to the sales manager and getting a new bumper cover put on.

Bumper cover is around $220 unpainted. Mine is doing it too, and even gluing wont keep it on. The little tabs are too weak and the black retainer under the headlight that locks onto the bumper is just not locking on tightly enough. You can't even get behind the joint to screw it together either.

This is interesting - My 2017 TRD Pro has the opposite "problem". The gap (near the headlight is very tight (touching) on the passenger side - tight enough that the paint is abrading (if you look really closely). It is the only body panel gap that isn't perfectly uniform. I took it to the dealer - they said (after some discussion) it was covered under warrantee & sent me to a body shop. The body shop guys advised me to not touch it. They said that the tabs are prone to getting a loose fit if disturbed & may not reattach as firmly again if the panel is popped off. They offered to look at it - but said that may make things worse, & it is non-adjustable anyway. I wasn't sure whether to believe them, but decided, for better or worse, to leave it as-is.

Toyota knows about this and I just had 2 new 4Runners (Limited and Trail) in the shop and had guys from Japan actually come out to see whats going on with them. Needles to say both of the 4Runners got new bumper covers. So Toyota is aware of the issue now I guess we wait n see.

They're sending someone out today to pick up my 4runner and take it back to the dealership (1.5 hour drive). I'm definitely going to make sure that it's replaced and fixed correctly before they bring it back. Thanks for the info, guys.

Poor engineering.

I believe I just talked with you on fb messenger.
Hopefully you get it corrected for good so I can tell my dealership how it was fixed.

same thing is happening to my 2014 4 runner . I took it to dealer and they didn’t do anything about it.. I called 1800-331-4331 and representative opened a case about it . I encourage everyone to call and report this. Maybe they will than do something about it . Zlata

Mine had this issue on the driver's side.

You can see it in this pic I took shortly after buying the truck:



I removed the bumper to install light bar behind grille, thought when I put the bumper back on I could resolve it. It didn't work so what I did was take a ~3 inch piece of 3m double sided tape and put it on the black bracket behind bumper, then when I installed the bumped I pressed it in on that spot and it fits flush now.



I stole this pic from someone else's thread to show the bracket.

Now whenever I remove the bumper (don't know why I would anymore) I will just use a new piece of 3m tape.

A story told in three parts...

Mine separated when I scraped a short parking pole. When you remove the bolts under the fender and pull the bumper liner and cover away you see that the piece under the headlight fits into a narrow vertical slit to help line it up with the adjacent piece. See the pic posted on #24, look just to the left of the arrow in the pic for reference for the vertical slit. There are no clips there that I could see. I did notice that a gentle tap in that area shifted the pieces behind the bumper cover slightly towards the engine about a 1/4 inch. I was able to get a long persuader behind the area and move it a liitle which helped get the area under the headlight lined up. But, I think I want to remove the whole bumper cover to understand that whole area better. The front of my 4Runner has taken a beating so I don't really care to paint it nice. I just used a bunch of touch up paint.
Low hanging nicely painted plastic pieces on a truck like this is annoying.

This thread needs a bump... I am sure more people are having this issue.

I did the fender mod recently and this starting happening immediately afterwards.

I had the same issue but on the passenger’s side. Bought as a used car and even the dealership couldn’t fix it. When I removed my bumper to install some LED fogs I was able to fix it.

When I had it all apart I checked for any broken tabs on the bumper and bracket bolted to the fender. Nothing was damaged. When I put it back together, it would pop out. Every time I snapped it into place, the part under the headlight would pop out. So I held the part under the headlight in place while snapping the part where the bumper and the fender meet. It’s been over two months and so far so good.

What are you holding where?

Headlight brackets has holes for bumper guide pins. If not seated correctly, the area along fender will have a gap.