[Mjolnir63]

Has anyone install the M-performance BMW rear diffuser on a 335i m-sport or a 340i m-sport themselves??

I was told by my dealer that the 335i diffusers work on the 340i LCI, as long as they have m-sport

If you did install the diffuser yourself, was it difficult? Did you have to take off the rear bumper or is it just removing the bolts and screws on the bottom?

Thanks in advance!

P.S.: This is the ebay link that I bought from. I have actually called the dealership myself to confirm that it does fit on a 340i.

http://www.ebay.com/itm/321969517713...%3AMEBIDX%3AIT

[Baldmonkey22]

Same place I got mine, 7 bolts on bottom and work from one end pulling towards you. clipping back in is kinda a pain in the middle section use something to back it up on the inside of the bumper so it doesn't flex when you go to push it back on and it will go easier.

Confirmed that part works for a 340

[Mjolnir63]

Originally Posted by Baldmonkey22

Same place I got mine, 7 bolts on bottom and work from one end pulling towards you. clipping back in is kinda a pain in the middle section use something to back it up on the inside of the bumper so it doesn't flex when you go to push it back on and it will go easier.

Confirmed that part works for a 340

Thanks for the quick reply and tips! No real difference starting from right or left correct? Honestly I am a little bit nervous about doing this myself as this is my first time ever doing something like this.

When you say "inside of the bumper, are you referring to the actual bumper or the diffuser?"

Thanks a lot!

[Portimao Blues]

I also have it and it was very easy to install. Just remove the bolts from underneath the existing diffuser, pop in the new one and put the bolts back in. I worked from left to right and it fit perfectly. I had mine painted Estoril Blue at a local body shop to match my body color and left the middle section black (like the picture in the Ebay listing you sent).

[Fronzdan]

It's actually quite easy. If you can get the rear wheels up a couple inches it'll be even easier. It's much easier than the front lip. There is a heat shield on the underside. You might want to bend that back gently so you can reach your hand directly behind where the diffuser pops in. This helps when you need to pop in the tabs.

[Mjolnir63]

Thanks for the replies guys! I have ordered the part and hopefully I can get my hands on it this week. I will take some pics once I am done with it

[DrifterX]

I bought a used M Performance diffuser a couple months ago from an owner who had an 2012 F30 and will be installing it soon after I get my 340i next week... if the weather isn't too bad. Glad to get more confirmation that it'll fit without problems

[Mjolnir63]

One last thing, for those that have the diffuser, what is the black string thing for?
Mine came with the diffuser and a black string thing.

Thanks!

[ronanz]

Originally Posted by psde2F30

One last thing, for those that have the diffuser, what is the black string thing for?
Mine came with the diffuser and a black string thing.

Thanks!

Masking the groove, center of diffuser if painted two-tone

.

[Mjolnir63]

Originally Posted by ronanz

Masking the groove, center of diffuser if painted two-tone

.

Oh cool! Thanks for the quick reply. So pretty much if I am going to leave it matte, I don't have to use it correct?

[ronanz]

Originally Posted by psde2F30

Oh cool! Thanks for the quick reply. So pretty much if I am going to leave it matte, I don't have to use it correct?

Correct

.

[Mjolnir63]

Originally Posted by ronanz

Correct

.

Got it, thanks!

[G30 B58]

If this diffuser is going on a light colored car, paint the area behind the vents a flat black.

[Mjolnir63]

Originally Posted by F32 N55

If this diffuser is going on a light colored car, paint the area behind the vents a flat black.

Originally I wanted to paint the entire thing sapphire metallic black since that's my car's color. But after seeing the matte finish I decided to just keep it matte XD

[smithf80]

Its incredibly easy. Takes minutes to swap, people here have already outlined the procedure.

[G30 B58]

Originally Posted by psde2F30

Originally I wanted to paint the entire thing sapphire metallic black since that's my car's color. But after seeing the matte finish I decided to just keep it matte XD

that's not my point.

[Mjolnir63]

Originally Posted by smithf32

Its incredibly easy. Takes minutes to swap, people here have already outlined the procedure.

Yes the diffuser is installed. Just wanted to make sure that piece of string isnt part of the install. Thanks all!

[2015M4inCT]

Anyone able to share some pics? Thanks

[AudiA4]

For the life of me, I've never been able to figure out what the difference is between this and the standard M Sport rear diffuser. Maybe I haven't looked closely enough, but if it's not that obvious...

[chazmink]

Originally Posted by AudiA4

For the life of me, I've never been able to figure out what the difference is between this and the standard M Sport rear diffuser. Maybe I haven't looked closely enough, but if it's not that obvious...

I think the difference is this one has vertical ribs. My 328 i M Sport diffuser did not have vertical ribs. I replaced it with a 335 M Sport diffuser after transplanting a 335 muffler and it doesn't have ribs either.

[Fronzdan]

Actually it's quite different. The standard M Sport doesn't have a diffusor, there is just a curved lower panel there. The M Perf Diffusor adds the fins in the middle and a couple accent fin-like things on either side. The piece extends the entire width of the rear bumper.