CSRT8 Rear Diffuser Installation

**nvan2007** · 01-03-2009, 03:15 AM

The following procedure outlines the requirements to install the Dodge Charger 05 - 07 SRT8 Rear Diffuser on the Dodge Magnum 05 - 07 (Non SRT8) Rear Bumper.

It turns out the Charger SRT8 Rear Diffuser is essentially a bolt on modification that will improve the look of your Magnum.

Acknowlegement:
Other members must be acknowledged for their contribution to this Knowledge Base modification article. This is to republish the procedural details as outlined in a previous thread subsequently removed.

Members were asking so I have prepared the following procedure, that found on this forum, and followed when I performed this modification to my 07 Magnum SXT with excellent results.

Here is the short notes on how to do it...

Just take your time, think it thru, double check everything, and you will be fine.

Mopar Part Number: 1BQ42RXFAA

Estimated Time To Complete:
The whole process from start to finish took me about 2 1/2 hours, mainly figuring things out and test fitting.

Tools Required:
#2 Philips Screw Driver
Flat Screw Driver
Plyers
Hand Drill
Assortment of Drill Bits
Metric Socket Set
Tin Snips or equivalent to trim rear bumper fascia.

[Installation Complete] Note the Diffuser has a lip that rests against the bumper not recessed and the diffuser is a perfect fit once the recess is trimmed.

[Dodge Charger SRT8 Rear Diffuser Mopar Part Number: 1BQ42RXFAA]

Installation Hardware:
You can obtain at any auto parts store.
12 1/2" or 3/4" Size 10 or 12 Stainless Interior Screws.

12 SS Washers for above.
12 U-Clips for the screws.

These slide over the bumper to screw on the diffuser.

2 Plastic Push In Fasteners for each side of the diffuser to bumper cover.

Installation Procedure:

1. Remove the rear bumper assembly, yes you must do this.
how to take rear bumper off?
Take your time and ensure to retain all plastic clips and fasteners.

2. Cut out the complete lower bumper insert area where it recesses, leaving the 3/4" recess for the diffuser 12 plastic tabs to fasten too.

I used a new set of tin snips and it cuts like butter. Other have used dremels, etc.

Compare the diffuser to the recess before you begin and you will understand.
And be careful with the diffuser tabs, they are only plastic and you don't want to break any tabs off.

Can't say this enough...
Very Important to leave the 3/4 lip that recesses into the bumper inset. Cut out the back of the inset only to the edge where it transitions out. If you cut off the transition then there is no cover material to screw the diffuser tabs to.

3. From the bumper cover painted side, position the diffuser in the cut out area. You will find the diffuser covers the remaining 3/4" strip you left for it to screw too and a little more, see picture 1 above.

4. Starting with the center 'plastic' tab on the diffuser, along the top.
Align with the bumper recess to the plastic tab hole.
Mark and drill the bumper cover on the recess strip for the U-clip and screw.

5. Slide a U-clip over the rear bumper where drilled and position your diffuser again in the bumper cover.

6. Screw in to almost snug and check your alignment side to side and against the bumper cover painted side.

If you missed your alignment, it will show right away and you can adjust. Just make sure you get the first 'center' screw in place and the diffuser evenly spaced on the bumper before you drill anything else.

7. Now work your way towards the outsides of the bumper, marking, drilling, and screwing in the diffuser. Remember to also check that the diffuser is tight against the bumper on the painted side as you tighten each screw. Take your time, especially for the outer edge screw installations.

8. At each end of the diffuser is an installation hole for a plastic fastener. You will find this does not line up with the bottom of the Magnum cover.

You will still have to fasten the cover to the diffuser at his location. Drill a hole thru both the diffuser and the bumper cover and install a plastic push in fastener. Or use a U-Clip and screw.

8. Reinstall the rear bumper.

9. Last Step: Attaching the lower portion of the diffuser to the vehicle.

I found that I could reuse the original 4 plastic push in fasteners

that were used to fasten the original rear bumper cover lower edge to the inner bumper plastic frame (dont know the correct name). This meant that I had to line up the existing holes (4) in the inner bumper frame with the bottom of the new diffuser. Then drill the appropriate size hole in the diffuser to accept the plastic push in fasteners. Once the fasteners were reinstalled, the diffuser was tight and looks factory.

Finally, I then cut off the remaining plastic tabs from the lower section (See second picture, tabs noted at top on the picture) of the diffuser as they served no use.

Alternate Member Methods to attach lower diffuser:

1. To connect the lower section of the diffuser, some members have fabricated a plastic plate they fasten to the plastic tabs on the bottom of the diffuser then to the trunk floor. Personally, I don't like that idea.

Take care...

**FreebirdSRT** · 06-11-2009, 09:40 AM

Nice write up, thanks....

**2005MagRt** · 08-31-2009, 10:35 PM

Hi, I was wondering if anyone has used p/n# 82209767 instead of 1BQ42RXFAA in this mod? I like the 82209767 fascia better looks wise. Thanks!

**argentmag** · 09-10-2009, 08:50 PM

I just ordered the 822 part # and I hope it fits up. Did you do it?

**bmeyer40** · 01-30-2010, 06:26 PM

Please update pictures that are missing. Thanks

Originally Posted by nvan2007

The following procedure outlines the requirements to install the Dodge Charger 05 - 07 SRT8 Rear Diffuser on the Dodge Magnum 05 - 07 (Non SRT8) Rear Bumper.

It turns out the Charger SRT8 Rear Diffuser is essentially a bolt on modification that will improve the look of your Magnum.

Acknowlegement:
Other members must be acknowledged for their contribution to this Knowledge Base modification article. This is to republish the procedural details as outlined in a previous thread subsequently removed.

Members were asking so I have prepared the following procedure, that found on this forum, and followed when I performed this modification to my 07 Magnum SXT with excellent results.

Here is the short notes on how to do it...

Just take your time, think it thru, double check everything, and you will be fine.

Mopar Part Number: 1BQ42RXFAA

Estimated Time To Complete:
The whole process from start to finish took me about 2 1/2 hours, mainly figuring things out and test fitting.

Tools Required:
#2 Philips Screw Driver
Flat Screw Driver
Plyers
Hand Drill
Assortment of Drill Bits
Metric Socket Set
Tin Snips or equivalent to trim rear bumper fascia.

[Installation Complete] Note the Diffuser has a lip that rests against the bumper not recessed and the diffuser is a perfect fit once the recess is trimmed.

[Dodge Charger SRT8 Rear Diffuser Mopar Part Number: 1BQ42RXFAA]

Installation Hardware:
You can obtain at any auto parts store.
12 1/2" or 3/4" Size 10 or 12 Stainless Interior Screws.

12 SS Washers for above.
12 U-Clips for the screws.

These slide over the bumper to screw on the diffuser.

2 Plastic Push In Fasteners for each side of the diffuser to bumper cover.

Installation Procedure:

1. Remove the rear bumper assembly, yes you must do this.
how to take rear bumper off?
Take your time and ensure to retain all plastic clips and fasteners.

2. Cut out the complete lower bumper insert area where it recesses, leaving the 3/4" recess for the diffuser 12 plastic tabs to fasten too.

I used a new set of tin snips and it cuts like butter. Other have used dremels, etc.

Compare the diffuser to the recess before you begin and you will understand.
And be careful with the diffuser tabs, they are only plastic and you don't want to break any tabs off.

Can't say this enough...
Very Important to leave the 3/4 lip that recesses into the bumper inset. Cut out the back of the inset only to the edge where it transitions out. If you cut off the transition then there is no cover material to screw the diffuser tabs to.

3. From the bumper cover painted side, position the diffuser in the cut out area. You will find the diffuser covers the remaining 3/4" strip you left for it to screw too and a little more, see picture 1 above.

4. Starting with the center 'plastic' tab on the diffuser, along the top.
Align with the bumper recess to the plastic tab hole.
Mark and drill the bumper cover on the recess strip for the U-clip and screw.

5. Slide a U-clip over the rear bumper where drilled and position your diffuser again in the bumper cover.

6. Screw in to almost snug and check your alignment side to side and against the bumper cover painted side.

If you missed your alignment, it will show right away and you can adjust. Just make sure you get the first 'center' screw in place and the diffuser evenly spaced on the bumper before you drill anything else.

7. Now work your way towards the outsides of the bumper, marking, drilling, and screwing in the diffuser. Remember to also check that the diffuser is tight against the bumper on the painted side as you tighten each screw. Take your time, especially for the outer edge screw installations.

8. At each end of the diffuser is an installation hole for a plastic fastener. You will find this does not line up with the bottom of the Magnum cover.

You will still have to fasten the cover to the diffuser at his location. Drill a hole thru both the diffuser and the bumper cover and install a plastic push in fastener. Or use a U-Clip and screw.

8. Reinstall the rear bumper.

9. Last Step: Attaching the lower portion of the diffuser to the vehicle.

I found that I could reuse the original 4 plastic push in fasteners

that were used to fasten the original rear bumper cover lower edge to the inner bumper plastic frame (dont know the correct name). This meant that I had to line up the existing holes (4) in the inner bumper frame with the bottom of the new diffuser. Then drill the appropriate size hole in the diffuser to accept the plastic push in fasteners. Once the fasteners were reinstalled, the diffuser was tight and looks factory.

Finally, I then cut off the remaining plastic tabs from the lower section (See second picture, tabs noted at top on the picture) of the diffuser as they served no use.

Alternate Member Methods to attach lower diffuser:

1. To connect the lower section of the diffuser, some members have fabricated a plastic plate they fasten to the plastic tabs on the bottom of the diffuser then to the trunk floor. Personally, I don't like that idea.

Take care...