Jump to content

Tonneau cover for CarbonPro??


Recommended Posts

Have installed a BakFlip MX4 on my GMC CarbonPro AT4.  Awesome vehicle.  Wanted a folding hard tonneau cover that exposed most/all of the bed.  This thread helped get me started.  From what I can tell this is similar to how the people in theStoops Auto video on YouTube managed it.  Here's the solve.  (Warning this most likely invalidates any warranty on the cover.)

 

1.  As has been noted in the thread there are a set of holes molded into the carbon pro bed, hidden behind the side panel covers.  One of these on each side nearest the tailgate has a rivet nut in place.  The others are designed for J-Nuts to be installed.  The threads on the rivet nuts are M6-1.  I built a tool similar to the one that comes with the GMC Tonneau cover to locate the holes and drill through the cover to expose them.  Used a 3/8" drill bit.

 

2.  Purchased a set of J-Nuts (Amazon).  The J-nuts I used fit perfectly.  These are:

Steel Tapped-Hole U-Style Clip-On Nut, Plain Finish, Metric, M6-1 Thread Size, For 0.8 mm-4 mm Material Thickness, 12 mm Edge Distance (Pack of 25).  Installed these through the square holes to line up with the round holes in the carbon pro bed.  Easy to figure out when you look at it!

 

3.  Purchased a matching set of Hex Head bolts.  The ones I used had to have the washer ground down flat on one site to fit into the rail of the MX4.  These are:

25 6-1.0 X 25mm Metric Hex Head Sems Bolts - Type CA

Ground down one side of the washers flat to near the head and installed these into the J-Nuts and RivetNuts on the sides.

 

4.  Then the tricky part -- the side rails of the MX4 are designed to be clamped to the walls.  Instead what I did was to cut slots into the back wall of the rails so that the rails could slide over the hex heads and be bolted into place.  To do this I did a lot of measuring to locate the placement of the bolts with respect to the AT4 rails (be nice if GMC documented some of this!).  Also set the rails into place to eyeball the locations.  Drilled 7/16" holes in the rails at the bolt locations.  Be careful to place something behind the rail so you only drill though the back wall of the rail.  Then cut using tin snips or similar slots to the holes.  

 

5.  Slid the rails down over the hex heads (flat washer side up) and bolted into place.  Had my son push down on the rail at each location while I tightened the bolts to ensure a proper tight fit of the rail to the bed wall cover.  See photo.

 

6.  After that just followed the instructions for the normal install of the MX4 tonneau cover.  Looks great, works like a charm.

 

IMG_8269.thumb.JPG.a191a7042752b0dcca55ec35cecd15de.JPG

Edited by TomCarbonPro
Added photo.
  • Like 3
Link to comment
Share on other sites

Excuse the dust, just got back from SandStorm!  This was the end result per the instructions from my previous post in this thread.  Took a few hours but was a great project for me and the boy!

 

IMG_8265.thumb.JPG.ae81670f156415bf033353a6fabccbff.JPG

Edited by TomCarbonPro
Added description.
Link to comment
Share on other sites

1 hour ago, TomCarbonPro said:

Have installed a BakFlip MX4 on my GMC CarbonPro AT4.  Awesome vehicle.  Wanted a folding hard tonneau cover that exposed most/all of the bed.  This thread helped get me started.  From what I can tell this is similar to how the people in theStoops Auto video on YouTube managed it.  Here's the solve.  (Warning this most likely invalidates any warranty on the cover.)

 

1.  As has been noted in the thread there are a set of holes molded into the carbon pro bed, hidden behind the side panel covers.  One of these on each side nearest the tailgate has a rivet nut in place.  The others are designed for J-Nuts to be installed.  The threads on the rivet nuts are M6-1.  I built a tool similar to the one that comes with the GMC Tonneau cover to locate the holes and drill through the cover to expose them.  Used a 3/8" drill bit.

 

2.  Purchased a set of J-Nuts (Amazon).  The J-nuts I used fit perfectly.  These are:

Steel Tapped-Hole U-Style Clip-On Nut, Plain Finish, Metric, M6-1 Thread Size, For 0.8 mm-4 mm Material Thickness, 12 mm Edge Distance (Pack of 25).  Installed these through the square holes to line up with the round holes in the carbon pro bed.  Easy to figure out when you look at it!

 

3.  Purchased a matching set of Hex Head bolts.  The ones I used had to have the washer ground down flat on one site to fit into the rail of the MX4.  These are:

25 6-1.0 X 25mm Metric Hex Head Sems Bolts - Type CA

Ground down one side of the washers flat to near the head and installed these into the J-Nuts and RivetNuts on the sides.

 

4.  Then the tricky part -- the side rails of the MX4 are designed to be clamped to the walls.  Instead what I did was to cut slots into the back wall of the rails so that the rails could slide over the hex heads and be bolted into place.  To do this I did a lot of measuring to locate the placement of the bolts with respect to the AT4 rails (be nice if GMC documented some of this!).  Also set the rails into place to eyeball the locations.  Drilled 7/16" holes in the rails at the bolt locations.  Be careful to place something behind the rail so you only drill though the back wall of the rail.  Then cut using tin snips or similar slots to the holes.  

 

5.  Slid the rails down over the hex heads (flat washer side up) and bolted into place.  Had my son push down on the rail at each location while I tightened the bolts to ensure a proper tight fit of the rail to the bed wall cover.  See photo.

 

6.  After that just followed the instructions for the normal install of the MX4 tonneau cover.  Looks great, works like a charm.

 

IMG_8269.thumb.JPG.a191a7042752b0dcca55ec35cecd15de.JPG

Nicely done!  Great job finding the J-nuts to match too... had I discovered those in advance, I might have similarly tried a custom aftermarket installation.  Folks take note of those part numbers/links!

Link to comment
Share on other sites

22 hours ago, TomCarbonPro said:

Excuse the dust, just got back from SandStorm!  This was the end result per the instructions from my previous post in this thread.  Took a few hours but was a great project for me and the boy!

 

IMG_8265.thumb.JPG.ae81670f156415bf033353a6fabccbff.JPG

Looks good but what about the hole to the left?Can that be plugged?

Link to comment
Share on other sites

New here, went in to the dealer last night to look at a CPO 2017 Sierra Denali but instead drove home in a 2020 6.2 Denali CarbonPro. 

 

I ordered through the dealers parts department - went with the soft version. The dealer is installing it for an additional $50.00. Ordered this morning, they said it will arrive tomorrow or the day after. I would love to have the locking feature, but to me it's not worth the extra $500.00 (they're over priced as it is). 

 

Did some research and read through this post, here's the link, price, and part numbers:

 

Soft Tri-Fold Tonneau Cover (Not Lockable)

Part No: 84791288

Price: $600.00

https://accessories.gmc.com/product/short-bed-soft-tri-fold-tonneau-cover-with-gmc-logo-(for-models-with-carbonpro-bed)-84791288?year=2020&make=GMC&model=Sierra 1500&categoryId=98027

 

Hard Tri-Fold Tonneau Cover (Lockable)

Part No: 84791287

Price: $1,100.00

https://accessories.gmc.com/product/short-bed-hard-tri-fold-tonneau-cover-(for-models-with-carbonpro-bed)-84791287?year=2020&make=GMC&model=Sierra 1500&categoryId=98027

Link to comment
Share on other sites

38 minutes ago, Daniel N said:

New here, went in to the dealer last night to look at a CPO 2017 Sierra Denali but instead drove home in a 2020 6.2 Denali CarbonPro. 

 

I ordered through the dealers parts department - went with the soft version. The dealer is installing it for an additional $50.00. Ordered this morning, they said it will arrive tomorrow or the day after. I would love to have the locking feature, but to me it's not worth the extra $500.00 (they're over priced as it is). 

 

Did some research and read through this post, here's the link, price, and part numbers:

 

That's a new part offering.... nobody here has mentioned it yet.  Let us know how it goes, but for me, I was only interested in a "hard" tonneau cover.

Link to comment
Share on other sites

I work for a Gm dealer and we came across this problem. We used a hole saw and cut the holes out nice and just clamped it in place. Just as I see a few on here have done. This is on a Extang Eceed cover. We figured that if a carbon pro box can with stand a hurricane wind 2x4 it can handle a hole and a clamp..

IMG_7586.jpg

Link to comment
Share on other sites

Oem soft cover installed. Folds up 2/3 of the way but not up completely to fully expose the bed. Can be secured in the 2/3 open position by buckles. Not lockable but the only way to open it is by opening the tailgate first (there is a latch on the under side of it). 

6D461919-E293-48E3-9878-1C7589D9A1FF.jpeg

Link to comment
Share on other sites

3 hours ago, Ryan Burton said:

You can buy the GMC cover from their website for 10% off this month.  Anyone have  pic of the GMC one installed yet?   I just ordered it and then got an email saying it was backordered!  

Read above.   Pictures all over this thread. 

Link to comment
Share on other sites

Passing along another possible carbon pro bed cover that installed without taking a hole saw or major modification to the truck bed. I really like the security of having a hard cover and like others have mentioned I don't like how other covers fold up and obstruct your view if you have something in the bed. I saw peragon's cover and figured it was worth a shot especially after reading this post and watching their install videos on the non-clamping version of the cover.

 

I got the Peragon cover https://www.peragon.com/ and, again, ordered the non-clamping version.

 

Additional items you'll need:

  1. 4 x J Nuts (this is a pack of 25)
  2. 4 x M6 Bolt (this is a pack of 25)
  3. 2 x 5/16" -18 Coupling Nut
    1. These were $5 a piece at my local ace hardware
  4. 2 x1 1/2" to 2" Length 5/16" -18 Bolt

Optional Items: in the instructions, you shim up the tonneau rails depending on your truck. They give you 40 washers to accomplish this but I didn't like the way it looked so I bought spacers in their place.

  1. 2 x  1/4" ID by 1/2" length Spacer
  2. 2 x  1/4" ID by 3/8" length Spacer

 

 

 

First step was taking off the plastic bed rail cover and installing the J nuts that folks have mentioned a couple times

 

IMG_0255.thumb.jpg.6bbf5cc955cb9f9468e2a7d2d0ab5815.jpg

 

Then I measured and drilled holes in the bed rail cover, for me the front was 10 1/2" from the leading edge and 7/16" up from the bottom. The back was 13 1/4" from the back of the rail cover and 1/2" up from the bottom.

 

Then you can install the "drill" attach bracket from the peragon cover package with the m6 bolts mentioned above. I installed it making the horizontal piece on the bracket as high as possible.

IMG_0259.thumb.jpg.5f983d8e89db0a6aa99c9af2ab88fdec.jpg

 

Once the brackets are installed you follow the normal instructions until you get to the shimming and the "ramp" alignment.

 

Instead of shimming with all the washers they provide, I used the spacer brackets mentioned above. The 1/2" high ones went in front and the 3/8" high ones went on the back brackets.

IMG_0267.thumb.jpg.01d36fc1d88d5a8c3f8268712dae6f2e.jpg

 

 

I used both the 2" long carriage bolt and coupling nuts for aligning the cover ramp where it needed to be. They provide a 5" bolt but for this truck bed was too deep and I needed something longer.IMG_0271.thumb.jpg.13f16d0822bc9044ae46c16876b9e454.jpg

 

 

I just installed it yesterday and I'm really happy with it. I think the gloss black on the top of the cover matches some of the piano black accents on the cab. I like how easily it opens, closes and how easy it is to remove the cover if not needed; the tonneau rails would take some effort to remove.

IMG_0276.thumb.jpg.27b199868829c1e8b0c1fe11071d368c.jpgIMG_0274.thumb.jpg.060ec162e5cedae6770906af42a378c5.jpgIMG_0273.thumb.jpg.6c5e41c6b5f86c05ce0c92060ace8a54.jpg

 

 

Only complaints are I wish it latched under the cover in back like other hard tonneau covers so you don't need an additional lock. The cover "ramp" is a little jenky with having to use a 5" bolt and the truck bed to align; I wish that were a little more cleaned up. 

 

 

Edited by bjt135
Link to comment
Share on other sites

On 1/31/2020 at 9:23 PM, Daniel N said:

Oem soft cover installed. Folds up 2/3 of the way but not up completely to fully expose the bed. Can be secured in the 2/3 open position by buckles. Not lockable but the only way to open it is by opening the tailgate first (there is a latch on the under side of it). 

6D461919-E293-48E3-9878-1C7589D9A1FF.jpeg

Looks good.  Can you post pics to show how it's mounted to CarbonPro bed?  Any modifications needed to install?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    247.6k
    Total Topics
    2.6m
    Total Posts
  • Member Statistics

    336,416
    Total Members
    8,960
    Most Online
    Lagonia
    Newest Member
    Lagonia
    Joined
  • Who's Online   3 Members, 0 Anonymous, 567 Guests (See full list)




×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.