M-technic/M5 bumper conversion

By Peter, update by BCM (May 2005, scroll down)


For those of you that are considering installing the M5 front and rear bumper, I hope my experience will help you. I have a 1999 540ia sport. After I purchased the car, I noticed the M-sport package that is available in Canada (soon in the US?). I really like the way the car looked. So, I decided to do the conversion to the M-sport look.

 Front M5 spoiler: While I was doing my research, I could not find the exact part numbers I needed to do the conversion. So, what I did was I went to my BMW dealer and told them that I wanted to install a M5 front spoiler, with all parts like the M5. The parts that appear on my invoice, along with the "list price", are as follows (some items from my car were reused in the install):

M5 front bumper parts list:
   Bumper panel 51-11-2-498-507 $454 Grille 51-11-2-496-285 $54.75
  Base plate 51-11-2-694-214 $31.60 Cover 51-71-2-498-989 $70.25
  Flap 51-11-2-693-539 $4.04 Cover 51-71-2-498-990 $50.50
  Gasket 51-11-8-191-149 $11.00 Flog Light (L) 63-17-2-228-613 $98.00
  Buffer Strip (L) 51-11-2-494-193 $15.80 Flog Light (R) 51-71-2-228-614 $98.00
  Buffer Strip (R) 51-11-2-494-194 $15.80 F.L. bracket 51-71-7-892-297 $83.80

Frame (L) 51-11-2-496-283 $13.50

F.L. bracket 51-71-7-892-298 $83.80
  Frame (R) 51-11-2-496-284 $13.50 Air Duct (L) 51-11-7-890-013 $18.60
  Nut (x12) 07-12-9-925-731 $0.08 Air Duct (R) 51-11-7-890-014 $18.60
  Nut (x2) 07-12-9-925-748 $0.32 Screening 51-71-2-498-988 $161.00
  Clip (x10) 51-41-8-204-057 $0.13 Bolt (x6) 07-11-9-901-294 $0.16
  Clip (x6) 51-71-8-176-503 $0.75  


Please note that on my install, the dealer changed out my lower front wheel liner, and installed the new brake air ram lower pieces, as well as a new lower M5 engine cover. A friend of my did the install without these parts.


After I finished with my front M5 bumper, I worked on the rear M-tech bumper. For the rear, a few items you need to know: With the new M-tech exhaust location, you will need to do some modification inorder to install any aftermarket exhaust. Also, the lower insert is for a large single exhaust tip. If you try to use a dual tip exhaust, you will need to trim part of the insert. Lastly, as an optional step, you can install the M5 liners. If you do not install the liners, there will be a 1/2 inch gap at the bottom corner of the bumper where it meets the wheel liners.


Here is a list of parts you will need for the rear conversion. Please note that much of the bumper internal parts, like the steel carriage, foam inserts, side brackets, and various nuts and bolts were reused from my car.

Rear M-Tech Bumper Parts List:
  Bumper panel 51-12-2-498-505 $498.50 Lower insert (single exhaust M-tech) 51-12-2-695-498 $67.50
  Flap (tow hook) 51-12-2-693-663 $6.75 M5 wheel liners Left side - 51-71-2-496-657 $66.25
  Buffer strip 51-12-2-498-733 $19.80 Right side - 51-71-2-496-658 $66.25
  buffer strip 51-12-2-498-734 $19.80 Rivet 51-11-8-174-185 $0.14 (need 20 of these)


I also installed the M5 deck spoiler.

M5 rear deck spoiler parts list
  Deck spoiler 51-71-7-901-594 $144.00 Adhesive 51-71-7-901-759 $9.30

Exhaust Options with the M-tech Bumper


One of the problem I ran into with the rear bumper install was getting the right exhaust fitment. I had a Supersprint exhaust priot to the install. As it turns out, I could not find any aftermarket exhaust that would fit the new exhaust location (closer to center and higher) without some sort of custom exhaust work. The only options I came up with were: 1. Go with a M5 OEM driver side exhaust (new bracket required and trim insert piece), 2. buy an aftermarket M5 driver side only exhaust (new bracket required and trim insert), 3. get a custom built exhaust, 4. modify my Supersprint to make it fit right (cutting the tips off and reweld it straight, also require new bracket and insert trimming), and lastly, 5. and perfit fitment way...reinstall my OEM 540 exhaust and go with a single or dual outlet.


After due consideration, I opted to reinstall my OEM exhaust, and had the shop custom build me a new 3" outlet pipe with a single 4" tip. I was extremely pleased with the end result. However, I wanted to make it sound like my old Supersprint, so I removed the center resonator for testing. Wow, I could not believe the sound!!! It actually sounds like the Supersprint, but the tone is a bit higher. If you didn't look at my exhaust, you would think I have some kind of aftermarket or custom exhaust by the way it sounded, and the way it looked.


Hope this will help those of you interested in the conversion. Please feel free to email me at E36pf@aol.com with any questions. Happy Motoring!!!





I have noticed some ommissions on Peter's M5 bumper post. I hope this parts list will be helpful for comparing and correcting.

I have done extensive research into the M-Tech modification and completed the job on my 1998 Arctic Silver 528i Sport. If you are considering this modification, know that doing good research is critical to getting this job done right. First, understand that some parts in this conversion will vary if you have a V8 or I6 BMW E39. Your local dealers computer will not always have correct data about the parts needed. The computer will say that cars from certain years are incompatible with some of the needed parts. BMW does offer a Retrofit M Aerodynamic kit, (Part number: 51-71-0-027-250), this kit includes the front and rear bumpers and many of the parts below, but there are additional V8 or I6 specific parts that are necessary to complete the job. Most importantly, you will need to get front wheel liners and F.L. brackets to hold the new lower engine cover and the bumper on. Some parts in the kit will be left over because it includes V8 and I6 parts.

A: The M5 front wheel liners (listed below, 989,990) do not have cut outs to allow air to reach brakes, but they can be cut out to work. The M-Tech liners listed next (899/832) are made to be used in this modification and have the cutouts. Both liners have an essential support piece that attaches to the bottom of the front bumper.

B: The aluminum F.L. (Fender Liner) brackets, also called screening, vary between the I6 and V8. They are critical to attaching the front engine cover (also called “engine belly pan”, “undercarriage”, or “screening”) to the vehicle and routing air back to the brakes.

C: The I6 uses a special fog light frame on the driver's side that allows air to be funneled back to the alternator. M5's and the 2003 540i Sports that I have seen do not use this system. The BMW retrofit kit includes both styles of driver's side fog light covers, just make sure not to neglect duct work that could over heat your alternator.

D: There are two styles of fog lights available. This is purely a cosmetic decision. The ones listed as “clear” are like those on 2003 540i Sports. The ones listed as “ribbed” are taken from the M5 parts list. The plugs on the M fog lights are different from your standard E39 and need to be spliced with the four new contacts and two plugs.

E: The M-Tech rear bumper is the same for 540/530/528/525. Parts listed are for a single side exhaust. There are a few choices for exhausts. You can modify your factory exhaust with a new tip (for around $150) or purchase a new OEM or after market exhaust. If you want the cosmetic appearance of a M5 quad exhaust there are a few aftermarket options out there (Eisenmann). A real M5 quad exhaust will require a different lower insert and major modifications to your undercarriage and spare tire well. M5 rear wheel liners are an option.

F: The M-tech grill mesh (280) is designed to connect to the ducts for the brakes. It has attachment points for the “T-grill” that snaps in the middle of the large air intake. Personal preference will decide if this is for you. The M5 grill mesh (285) can be modified to work by drilling holes in the mesh and using cable ties to hold the ducts on.

G: I'm not sure why there are different part numbers for the actual front bumper piece. Just make sure you order one that will be compatible with your PDC or headlight washers if you have those options. I got the 507-part number from the M5 parts list. I got the 377 with my kit and it did not have headlight washers. The BMW parts screen had a “M-PDC” notation next to the 377 in the computer. I guess it meant “minus PDC”. My car does not have PDC and the 377 bumper installed perfectly. Most people do the install with the 507. Also note that some hardware can be reused in the install.


51-11-2-498-507 Front Bumper ($454 retail) (M5) or use below
51-11-7-894-377 Front Bumper (no headlight washer/no PDC)
51-71-2-498-939 Front Air Duct $42.00
51-11-7-890-013 Air Duct Left $13.38
51-11-7-890-014 Air Duct Right $13.38
51-11-2-693-539 Front Tow Flap $6.12
51-11-2-494-193 Front Buffer Strip Left (Shadowline) @$11
51-11-2-494-194 Front Buffer Strip Right (Shadowline) @11
51-11-8-159-361 Support Left (Old one can be reused) $3.30
51-11-8-159-362 Support Right (Old one can be reused) $3.30
51-11-8-191-149 Gasket x2 (2125MM) $9.00
51-11-2-495-280 Black mesh grille w/ for T-grill and ducts $23.04
51-11-7-893-048 Web Center (commonly called T-Grill) $26.40
51-11-2-694-214 License plate frame (if required by your state)
61-13-0-007-272 Contact To Fog Lamp x4
61-13-8-364-498 Plug For Fog Lamp x2
63-17-2-228-613 Fog Lamp Left RIBBED LENS $71.00
63-17-2-228-614 Fog Lamp Right RIBBED LENS $71.00
63-17-7-894-017 Fog Lamp Left CLEAR LENS $71.00
63-17-7-894-018 Fog Lamp Right CLEAR LENS $71.00
(Some parts below vary if you have an I6 or V8)
51-11-2-695-761 Alternator Air Duct $19.02 (528/525/530)
51-11-2-695-762 Air Duct, Oil Cooler (540)
51-11-7-891-421 Fog Light Frame right w/Alternator cut out(528/530)
51-11-2-496-283 Fog Light Frame left (540/M5) $9.72
51-11-2-496-284 Fog Light Frame right (All) $9.72
51-71-2-498-989 Wheel liner/support Right (FOR M5) (no ducts)
51-71-2-498-990 Wheel liner/support Left (FOR M5) (no ducts)
51-71-2-694-899 Wheel liner/support Right (540/530/528/525)$60.80
51-71-2-694-832 Wheel liner/support Left (540/530/528/525)$60.80
51-71-7-892-297 F.L. metal bracket/support duct (540/M5) $60.36
51-71-7-892-298 F.L. metal bracket/support duct (540/M5) $60.36
51-71-7-892-295 F.L. metal bracket/support duct (530/528/525) $32
51-71-7-892-296 F.L. metal bracket/support duct (530/528/525) $32
51-71-2-498-988 Screening (540/M5) (front engine cover) $121.68
51-71-2-695-680 Front Engine Cover (525/528/530) $57.80


51-11-2-498-507 Front Bumper ($454 retail) (M5) or use below
51-11-8-174-185 Expanding Rivet x30 Schwarz
51-41-8-201-057 Axial Securing Clip x10
51-11-8-242-250 Phillips Screws x2 TS 5x20
07-12-9-925-717 Body Nut x2
07-11-9-916-922 Hex Head Screw x11


M-TECH REAR BUMPER (Parts the same for I6 or V8)
51-12-2-498-505- Rear bumper panel $358.68
51-12-2-498-733- Rear Buffer Strip Left (Shadowline) $14.28
51-12-2-498-734- Rear Buffer Strip Right (Shadowline)$14.28
51-12-2-693-663- Rear Tow Flap $6.12
51-12-2-695-498- Insert for single side exhaust $48.60
51-11-1-970-389- Bracket ($3.84 each) x2 $7.68
51-12-8-211-436- Sliding Piece ($.12each) x2 $0.24


07-12-9-925-748 Nut (x2) 51-71-8-176-503 Clamp (x20)
07-11-9-916-966 Sheet Nut (x4) 51-71-8-218-852 Screw Plug (x2)
07-11-9-901-294 Hex head Screw (x20) 51-71-8-218-323 Screw Plug (x8)
07-12-9-925-731 Body Nut x(20) 51-71-8-229-003 Expanding Rivet (x12)
51-16-1-881-149 Expanding Rivet (x12) 51-71-8-195-383 Circlip (x12)


FYI if you hate the T-Grill and want M5 look
51-11-2-496-285 M5 mesh Grille (won't work with ducts unless modified)


51-71-2-496-657- Liner left ($55 retail approx) 51-71-2-496-658- Liner right ($55 retail approx)


51-71-7-901-594- Rear lip spoiler $103.68 51-71-0-141-495- 3M adhesive tape $6.72


51-13-2-497-261- M5 Grille left $24.78 51-13-2-497-262- M5 Grille right $24.78


51-71-7-892-268 Right Filling Insert $5.75 51-71-7-892-267 Left Filling Insert $5.75
(I don't know what they are, and did not need them to finish)


M-AERODYNAMIC KIT has these, but you won't need them
51-11-7-891-931 Cover Left 51-11-7-891-932 Cover Right
(These block the air ducts for T-Grill installation on an M5)