1. Can you point me to the “brace” you refer to? I go through these gaskets every couple hundred miles :(
2. What’s the bolts part numbers for the flange where these donuts go? I can’t find them anywhere, just the manifold bolts. ( Andy, 12/28/2024 )

The "brace" is just a piece of metal bar cut to length and welded to 3" u-clamps on either end. We don't supply the metal bar but we do have the 3" u-clamps available: https://www.ultrarvproducts.com/U-3-3-U-Clamp

It uses studs and nuts to attach the manifold to the down pipe where the donut is located. Here are links to those items, stud: https://www.ultrarvproducts.com/11589264-Stud-Exhaust-Manifold-To-Pipe and nut: https://www.ultrarvproducts.com/11514597-8.1l-Factory-Exhaust-Manifold-To-Pipe-Flange-Nut

I've had similar questions to those previously asked by others, you're answers are helpful. Thank you - I'm ordering a pair. Can you give a simple description of the "brace" you suggest? Do the downpipes brace to a chassis component, or to each other? ( Ricky Hunkins, 01/21/2024 )

Hi Ricky,

        When I have installed those braces, I just use a length of 3/4" square steel tubing, and two 3" exhaust clamps. Clamp them onto the pipe with the treaded ends facing each other and then weld the square tube to the saddle of the clamps. Doing it this way allows you to remove the brace when needed. This brace can be installed anywhere on the downpipes fairly close to the junction for the catalytic converters.

What are the dimensions OD/ID? ( Jim FLoyd, 03/11/2023 )
OD is 3", ID is 2.4".
Will this fit my vehicle ( Caleb Coulson, 03/02/2023 )
Hello Caleb, we do not have a way to verify that as our VIN search only covers Workhorse chassis. You will need to verify the part # with a GM parts department . 
HELLO,
I HAVE A WORKHORSE W22 8.1L , IS THIS THE CORECT EXHAUST DONUT? IS IT HEAVY DUTY OEM, I HAVE TRIED SEVERAL AFTERMARKET ONES AND THEY DON'T FIT TIGHT AND BURN OUT
THANKS BOB ( ROBERT MCCORD, 07/28/2019 )

Robert,

    That is the correct seal for your VIN. This is the exact fit replacement not aftermarket, you should have better luck with fitment if you order this part. We install a brace between the pipes in front of the flanges where the downpipe connects to the catalytic convertors. This prevents the pipes from moving and wearing on the seal.