MatthewAMEL
Seasoned Member
Correct. Although the CF2 diffuser removes the ability to open the trunk with your foot.
Carbon fiber PN database.
- Thread starter Jameson's Viggen
- Start date
Head Hunter
Seasoned Member
Looks like GM might have changed the PN for the CF Rear Wing on a 5VBW - 85517784
When I searched by PN for the rear wing listed above, nothing came up.
Sphinx
Seasoned Member
Yes, you can. If you do both kits, parts will cost a little more than the factory price+labor. Your dealer might give you a good price on that though.
jonnywaffles11
Seasoned Member
Depends on if you have a 4 or a 5. On the 4 you'll see a page or so back that the bumper is different. The dealer would not be able to install the dive planes. All other parts on the 4 and the 5 should be direct replacements.
jonnywaffles11
Seasoned Member
GM's original supplier for carbon fiber went out of business during the pandemic with little notice to GM (that's what prompted the cf shortage). GM has since awarded these parts to a new supplier and has new tooling for everything. You will likely see that all numbers on the list are likely outdated at this point (old vendor would be using 84xxxxx while new one seems to be using a supersession 85xxxxx). This gives them traceability back to the supplier in case of defects or warranty. Dealers likely have a replace by note in their systems that if you give them the old number they will reach out saying it's no longer available and point you to a superseded sku. At least that's how we do it for the automotive aftermarket. When I tried to order the front splitter under a 84xxxx number the parts site reached out a few days later with the current 85 number that didn't link to anything on the parts site at the time.
It be a 5bw.
jumpmanjay
Seasoned Member
Two places I tried just said it was no longer available with no option for the new sku.
Dirkbg
Seasoned Member
Is anyone interested in a step-by-step with photos on modifying the standard 4BW bumper for dive planes? I didn't like the paint match for the replacement bumper and went back and modified my original which is really what I should have done initially. I was worried about cutting up stuff but as it turns out it's really not complicated, just takes a little time (and money for carbon parts...). If I do, should I place it in this thread or start another?
Dirkbg
Seasoned Member
To modify the stock 4BW bumper for the dive planes means you have to cut 5 slots on each side for the dive plane tabs to engage a support on the back side. The stock bumper does not have the support, so until someone markets a matching part, you'll have to get a factory slotted bumper. I ordered one at a local GM dealer at MSRP and it was $300 + $75 core + tax (F Fascia - GM 85153560). You can probably return the primer bumper as the core after removing the bracket supports...
Removing the support is easy. I used my Harbor Freight trim tool kit, slipping in one tool from the bottom and another from the top on the outside top weld. After it popped you can just pull on it and the others broke loose one by one. If any stick, you can use the trim tool to help it along. This is the result:
With the support removed, you now have to cut the slots in the existing bumper. It is convenient the standard bumper provides markings for both the support outline and the slots, so you don't need a template:
The outside slot support is already provided in the standard piece shown in red above. You just need to cut the outer cover there. I had already stripped my standard bumper because I tried using the new bumper, but I didn't like the color match and decided to re-use my original with the modification. That made it easier to lay the bumper on its face to mark and cut it. The curved shape is still tricky, and I propped the upper side to the back of a chair using microfiber where the bumper touched the carpet or chair to protect the paint.
To help see the slot markings, I outlined them with tape. There are double lines for the slot markings. Use the outer line to tape and cut.
I found the fastest and most effective way to cut the slots was to use a Dremel cutting disk to slit through the middle of the slot, then use a sharp Exacto knife to shave (not cut) up the the edges. Use it like shaving dark chocolate curls for baking, pushing the blade through as you push it forward. As you get to the ends, use a RotoZip tool bit to round the ends. I felt rounding the ends would reduce chances of splitting a sharp corner might cause, and matches the OEM slots. With the grill parts installed, you may have trouble using the Dremel cutting blade on one of the slots. You may have to use a 1/8 drill bit, then RotoZip the slot enough to use the Exacto blade. Do all the work from the back side so you don't risk scratching the paint on the front. The finished slots looked like this:
Finally, I used the dive plane to locate the support bracket to verify the fit. When I was happy with that I scuffed the back of the bumper and face of the support with sandpaper and used J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe applied at the previous weld points, then used the clips to hold in place while it cured. When you first apply it, you can shift the support bracket slightly to match the outline perfectly. The factory installed bracket didn't match the outline as accurately as mine did. This is the result of the epoxy attachment, and it holds better than the factory weld.
Then for me it was just a matter of moving all the grill parts back over again, and reinstalling the bumper cover. By the way, I never jacked up the car to remove the bumper. You can get to all the screws easily without doing that. And just turning the front wheels one way or the other at the start is all that's needed to get the wheel well screws on both sides.
The final result turned out great, and I have matching paint again
As a final note, I used factory OEM dive planes. The tabs on the OEM dive planes are a consistent 2.4 mm thickness. If you use non OEM dive planes the tabs may be different and require either wider slots or thinning of the tabs. I suggest test fitting the dive planes with the factory slotted bumper before you remove the inner supports. You'll also need 10 clips. I used these on Amazon https://www.amazon.com/dp/B09PRDWDWG?psc=1&ref=ppx_yo2ov_dt_b_product_details . They are physically identical, but seem to be a different (harder and potentially more brittle) plastic. But I installed and uninstalled the clips several times and they held up well.
I did notice the non-OEM wheel deflector carbon doesn't match the OEM splitter and dive plane carbon. The hazards of mix and match parts I guess (I couldn't take it. I got the OEM deflectors now and stored away the non-OEM parts )
Removing the support is easy. I used my Harbor Freight trim tool kit, slipping in one tool from the bottom and another from the top on the outside top weld. After it popped you can just pull on it and the others broke loose one by one. If any stick, you can use the trim tool to help it along. This is the result:
With the support removed, you now have to cut the slots in the existing bumper. It is convenient the standard bumper provides markings for both the support outline and the slots, so you don't need a template:
The outside slot support is already provided in the standard piece shown in red above. You just need to cut the outer cover there. I had already stripped my standard bumper because I tried using the new bumper, but I didn't like the color match and decided to re-use my original with the modification. That made it easier to lay the bumper on its face to mark and cut it. The curved shape is still tricky, and I propped the upper side to the back of a chair using microfiber where the bumper touched the carpet or chair to protect the paint.
To help see the slot markings, I outlined them with tape. There are double lines for the slot markings. Use the outer line to tape and cut.
I found the fastest and most effective way to cut the slots was to use a Dremel cutting disk to slit through the middle of the slot, then use a sharp Exacto knife to shave (not cut) up the the edges. Use it like shaving dark chocolate curls for baking, pushing the blade through as you push it forward. As you get to the ends, use a RotoZip tool bit to round the ends. I felt rounding the ends would reduce chances of splitting a sharp corner might cause, and matches the OEM slots. With the grill parts installed, you may have trouble using the Dremel cutting blade on one of the slots. You may have to use a 1/8 drill bit, then RotoZip the slot enough to use the Exacto blade. Do all the work from the back side so you don't risk scratching the paint on the front. The finished slots looked like this:
Finally, I used the dive plane to locate the support bracket to verify the fit. When I was happy with that I scuffed the back of the bumper and face of the support with sandpaper and used J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe applied at the previous weld points, then used the clips to hold in place while it cured. When you first apply it, you can shift the support bracket slightly to match the outline perfectly. The factory installed bracket didn't match the outline as accurately as mine did. This is the result of the epoxy attachment, and it holds better than the factory weld.
Then for me it was just a matter of moving all the grill parts back over again, and reinstalling the bumper cover. By the way, I never jacked up the car to remove the bumper. You can get to all the screws easily without doing that. And just turning the front wheels one way or the other at the start is all that's needed to get the wheel well screws on both sides.
The final result turned out great, and I have matching paint again
As a final note, I used factory OEM dive planes. The tabs on the OEM dive planes are a consistent 2.4 mm thickness. If you use non OEM dive planes the tabs may be different and require either wider slots or thinning of the tabs. I suggest test fitting the dive planes with the factory slotted bumper before you remove the inner supports. You'll also need 10 clips. I used these on Amazon https://www.amazon.com/dp/B09PRDWDWG?psc=1&ref=ppx_yo2ov_dt_b_product_details . They are physically identical, but seem to be a different (harder and potentially more brittle) plastic. But I installed and uninstalled the clips several times and they held up well.
I did notice the non-OEM wheel deflector carbon doesn't match the OEM splitter and dive plane carbon. The hazards of mix and match parts I guess
(I couldn't take it. I got the OEM deflectors now and stored away the non-OEM parts )
Last edited:
RDATLTE
FKA: Sticker Boy & CT4-V Blackwing
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- V-Series Cadillac(s)?
- 2023 CT4-V Blackwing Road Atlanta IMSA Track Edition
To modify the stock 4BW bumper for the dive planes means you have to cut 5 slots on each side for the dive plane tabs to engage a support on the back side. The stock bumper does not have the support, so until someone markets a matching part, you'll have to get a factory slotted bumper. I ordered one at a local GM dealer at MSRP and it was $300 + $75 core + tax (F Fascia - GM 85153560). You can probably return the primer bumper as the core after removing the bracket supports...
View attachment 19565
Removing the support is easy. I used my Harbor Freight trim tool kit, slipping in one tool from the bottom and another from the top on the outside top weld. After it popped you can just pull on it and the others broke loose one by one. If any stick, you can use the trim toll to help it along. This is the result:
View attachment 19566
With the support removed, you now have to cut the slots in the existing bumper. It is convenient the standard bumper provides markings for both the support outline and the slots, so you don't need a template:
View attachment 19573
The outside slot support is already provided in the standard piece shown in red above. You just need to cut the outer cover there. I had already stripped my standard bumper because I tried using the new bumper, but I didn't like the color match and decided to re-use my original with the modification. That made it easier to lay the bumper on its face to mark and cut it. The curved shape is still tricky, and I propped the upper side to the back of a chair using microfiber where the bumper touched the carpet or chair to protect the paint.
To help see the slot markings, I outlined them with tape. There are double lines for the slot markings. Use the outer line to tape and cut.
View attachment 19571
I found the fastest and most effective way to cut the slots was to use a Dremel cutting disk to slot through the middle of the slot, then use a sharp Exacto knife to shave (not cut) up the the edges. Use it like shaving dark chocolate curls for baking, pushing the blade through as you push it forward. As you get to the ends, use a RotoZip tool bit to round the ends. I felt rounding the ends would reduce chances of splitting a sharp corner might cause, and matches the OEM slots. With the grill parts installed, you may have trouble using the Dremel cutting blade on one of the slots. You may have to use a 1/8 drill bit, then RotoZip the slot enough to use the Exacto blade. Do all the work from the back side so you don't risk scratching the paint on the front. The finished slots looked like this:
View attachment 19574
Finally, I used the dive plane to locate the support bracket to verify the fit. When I was happy with that I scuffed the back of the bumper and face of the support with sandpaper and used J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe applied at the previous weld points, then used the clips to hold in place while it cured. When you first apply it, you can shift the support bracket slightly to match the outline perfectly. The factory installed bracket didn't match the outline as accurately as mine did. This is the result of the epoxy attachment, and it holds better than the factory weld.
View attachment 19575
View attachment 19576
Then for me it was just a matter of moving all the grill parts back over again, and reinstalling the bumper cover. By the way, I never jacked up the car to remove the bumper. You can get to all the screws easily without doing that. And just turning the front wheels one way or the other at the start is all that's needed to get the wheel well screws on both sides.
The final result turned out great, and I have matching paint again
View attachment 19577
As a final note, I used factory OEM dive planes. The tabs on the OEM dive planes are a consistent 2.4 mm thickness. If you use non OEM dive planes the tabs may be different and require either wider slots or thinning of the tabs. I suggest test fitting the dive planes with the factory slotted bumper before you remove the inner supports. You'll also need 10 clips. I used these on Amazon https://www.amazon.com/dp/B09PRDWDWG?psc=1&ref=ppx_yo2ov_dt_b_product_details . They are physically identical, but seem to be a different (harder and potentially more brittle) plastic. But I installed and uninstalled the clips several times and they held up well.
Dirkbg
Seasoned Member
At the risk of getting too far off topic (but related to the Dive Plane installation), since I removed the bumper (twice) I thought I'd pass on a couple observations.
I used the service manual guide for removal. You really only need a T15 torx bit for the dozens of screws and a 7 mm box end wrench for the bolt that holds the bumper to the fender . Very straightforward.
The tricky part is disconnecting the wiring harness. The attached video shows how it is disconnected. It's tight access even with all the screws and the clips removed and detached. You will see only the end to the left in the video. You'll use your fingernail to pull the red tab outward toward you, then grab the outer sleeve and pull it outward toward you while using your other hand to hold the inner receptacle wires.
There are clips along the bumper to fender interface, but they simply pull apart (outward) carefully. There are three clips under the headlight that you can't see until you pull the outer cover out enough that I broke the two welds shown in the photo. That's how I found how weak the welds are, and how well the J-B Weld 50139 Plastic Bonder Body Panel Adhesive worked to repair it. Use only a thin layer and clamp it when curing since it will set the depth of the bumper to the headlight. Once you can see the clips, I used a paint can opener tool to detach them. The third inner tab doesn't seem to be as strong as the two outer ones.
Maybe someone knows a better tool for those under headlight clips, but I don't know what it would be. At least you can see here what you're dealing with.
I used the service manual guide for removal. You really only need a T15 torx bit for the dozens of screws and a 7 mm box end wrench for the bolt that holds the bumper to the fender . Very straightforward.
The tricky part is disconnecting the wiring harness. The attached video shows how it is disconnected. It's tight access even with all the screws and the clips removed and detached. You will see only the end to the left in the video. You'll use your fingernail to pull the red tab outward toward you, then grab the outer sleeve and pull it outward toward you while using your other hand to hold the inner receptacle wires.
There are clips along the bumper to fender interface, but they simply pull apart (outward) carefully. There are three clips under the headlight that you can't see until you pull the outer cover out enough that I broke the two welds shown in the photo. That's how I found how weak the welds are, and how well the J-B Weld 50139 Plastic Bonder Body Panel Adhesive worked to repair it. Use only a thin layer and clamp it when curing since it will set the depth of the bumper to the headlight. Once you can see the clips, I used a paint can opener tool to detach them. The third inner tab doesn't seem to be as strong as the two outer ones.
Maybe someone knows a better tool for those under headlight clips, but I don't know what it would be. At least you can see here what you're dealing with.
Last edited:
GR630
New Member
Thanks so much for the photos and write up. Just got my 4BW this week and already ordered all the carbon bits from Tapout. Seeing that the OE bumper was already marked sealed the deal on doing the dive planes. I'm going to go a different approach and see if I can custom make my own brackets out of abs before I drop $300 just for a couple of brackets. Worst case, I end up buying the bumper, but figured its worth a shot. I'll try to post pics when I do, but I suck at taking detailed pics while in the midst of a project.
jvp
Seasoned Member
OEM 5BW front carbon fiber deflectors for sale if anyone's interested:
www.cadillacvnet.com
For Sale: CT5-V Blackwing Carbon Fiber Front Deflectors: $1000
These two are for sale, new, unused, purchased directly from a Cadillac dealership: front side wheel deflector right PN 84490400 front side wheel deflector left PN 84490401 Asking $1000 for both (they cost me $1000 each) and will ship anywhere in the US. I'm purchasing Terrance's front...
www.cadillacvnet.com
ukcats12
Seasoned Member
Got an email from one of the online parts stores claiming the front splitter for the CT5 BW with part number 84432226 is discontinued. Is there a new part number anywhere?
rubberduck
Seasoned Member
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- V-Series Cadillac(s)?
- 22 CT5V BW Shadow Metallic 6M
I was at my local Cadillac dealer today to check up on my splitter that has been on order since December. I asked them to look into a PN change and they said there is not another one and this one is valid. However my ETA date has slipped for the 5th time to end of October. I have zero confidence in this date. My feeling is that GM is going to be using all the ones they have for production. The only possibility I see for an OEM splitter is to randomly call around dealers and maybe get lucky. But, they are going to charge a fortune to ship it.
Ergoc5
Seasoned Member
Yeah it keeps shifting for me too...I ordered one in Jan to replace my damaged CF splitter but I think I am just going to fix this one and get it painted gloss black
diddy837
Seasoned Member
The dealership should tell you who has one in stock. And not sure if there in production anymore. 2024 models are getting a slight facelift
rubberduck
Seasoned Member
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If they change the splitter for 2024 it would be easier to get one for my 2022. No way GM is going to stop making parts for a one year old car, in fact, that might even be illegal.
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