[McLaren720s]

I have the exact same issue with TWO rear diffusers I bought (2 different sellers). The right top side just below the reflector keeps popping out and is not flushed with reflector. I press it in, I hear the tab click and as soon as I let go, it pops out.

I'm thinking I might need to trim or shave the back of the diffuser a little to help settle and become flush with the reflector.

Has anyone else had this issue and how did you solve it?

I like the diffuser and don't want to return it AGAIN. And since I'm having the exact same issue I'm starting to think my rear bumper is not even on both sides.

[mbanks21]

Are there tabs on each end? Your best bet is to take the bumper off, push the tabs in and put a bolt/screw/nut/whatever to hold it tight in place.

[johnung]

Originally Posted by McLaren720s

I have the exact same issue with TWO rear diffusers I bought (2 different sellers). The right top side just below the reflector keeps popping out and is not flushed with reflector. I press it in, I hear the tab click and as soon as I let go, it pops out.

I'm thinking I might need to trim or shave the back of the diffuser a little to help settle and become flush with the reflector.

Has anyone else had this issue and how did you solve it?

I like the diffuser and don't want to return it AGAIN. And since I'm having the exact same issue I'm starting to think my rear bumper is not even on both sides.

It's been a year since I installed mine but your complaint sounds vaguely familiar so it may have happened to me during my installation.

I know that I watched the installation video on YouTube from Kies Motorsports where I bought the diffuser.

I'd suggest removing the reflectors and wait to install them after the diffuser is in place. Try changing the order that you are pushing in connections: left to right, right to left, center out, outside in, etc. Where it's popping out there may just be an edge where two pieces of plastic come together where one is supposed to go on top of the other and they are accidentally reversed.

I wouldn't start thinking that you need to trim, cut or sand anything. One of the things above will probably solve it. Good luck!

[McLaren720s]

Originally Posted by johnung

It's been a year since I installed mine but your complaint sounds vaguely familiar so it may have happened to me during my installation.

I know that I wanted the installation video on YouTube from Kies Motorsports where I bought the diffuser.

I'd suggest removing the reflectors and wait to install them after the diffuser is in place. Try changing the order that you are pushing in connections: left to right, right to left, center out, outside in, etc. Where it's popping out there may just be an edge where two pieces of plastic come together where one is supposed to go on top of the other and they are accidentally reversed.

I wouldn't start thinking that you need to trim, cut or sand anything. One of the things above will probably solve it. Good luck!

Thanks. I’ll try removing the reflectors first and go from there.

[wdeerfield]

I had a similar problem with my f30 and removing the reflectors made it that much easier. it also give you a chance to wrap the reflectors in gloss black vinyl to match.

[IanW555]

I had the same problem, I think it is because of the gloss paint, the paint seems to get in the way on the tabs. My problem was also on the right. In the end not entirely sure how but I managed to get it to stay. Fingers crossed, but has done a few thousand miles now and still there. I also removed the reflectors

[FirstBMWLA]

Which diffuser is it?
I'm looking for a seller that has mperf style already done gloss black for F36 if that's available anywhere.

[McLaren720s]

Originally Posted by FirstBMWLA

Which diffuser is it?
I'm looking for a seller that has mperf style already done gloss black for F36 if that's available anywhere.

ABS rear bumper diffuser for BMW... https://www.amazon.com/dp/B07QQX8BK1...p_mob_ap_share

I can now confirm that it fits and looks great! After popping out the reflectors it was easy to adjust the diffuser and make it fit.
Thanks to everyone who suggested that!

[johnung]

Originally Posted by FirstBMWLA

Which diffuser is it?
I'm looking for a seller that has mperf style already done gloss black for F36 if that's available anywhere.

Originally Posted by FirstBMWLA

Which diffuser is it?
I'm looking for a seller that has mperf style already done gloss black for F36 if that's available anywhere.

I haven't seen any that are sold in gloss black. It's usually in that standard matte black plastic. I've found that you can deepen the black and gloss it up just by applying a product meant to do that. Check out the armorall-type section of your local auto parts store and you'll find products promoting those features. I apply those to my plastic rear diffuser and it looks great.