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I just took my 2020 glc 63 to get a secondary cat delete and the shop said they couldn’t do it due to the location and piping of them. Anybody else have this issue when doing so or were their shops able to get it done? If so, how did they do it. Feel free to pm as well
If you're talking about the downpipes, you either have to cut the existing ones or drop the whole transmission to remove them. There's a few threads about it, not the easiest procedure either way.
"I just did this myself, and it's surprisingly easy. If you can remove the mid-pipe (H-pipe), which involves just four clamps and a clip, you'll have easy access to the catalytic converters. Using a small crowbar, you can break away the material. The entire process took me about 45 minutes from start to finish. It's one of the most worthwhile free mods I've done in a long time!
"I just did this myself, and it's surprisingly easy. If you can remove the mid-pipe (H-pipe), which involves just four clamps and a clip, you'll have easy access to the catalytic converters. Using a small crowbar, you can break away the material. The entire process took me about 45 minutes from start to finish. It's one of the most worthwhile free mods I've done in a long time!
"I just did this myself, and it's surprisingly easy. If you can remove the mid-pipe (H-pipe), which involves just four clamps and a clip, you'll have easy access to the catalytic converters. Using a small crowbar, you can break away the material. The entire process took me about 45 minutes from start to finish. It's one of the most worthwhile free mods I've done in a long time!
Asking again for help with pictures? Or detailed writeup
Asking again for help with pictures? Or detailed writeup
I did this a while back — overall, it’s a pretty easy job, if you have access to a lift.
Start by removing the two clamps that connect the mid/back exhaust to the downpipe. Make sure you have something in place to support the lower section when it drops so you don’t put stress on the other brackets.
Once the sections are separated, you’ll have access to the secondary cats which is a foot from the entrance of the pipe. (See attached pic)
Tools you’ll need:
Long crowbar
Hammer
Flashlight
(Optional but helpful) scope camera to check your work. I have a Milwaukee M12 Spector 360.
Use the crowbar and hammer to carefully chisel out the OPF filter. Take your time to make sure you remove everything — that’s where the scope camera comes in handy.
That’s it. The whole process took me about an hour.
Last edited by Killswitch747; Sep 29, 2025 at 11:17 AM.
I did this a while back — overall, it’s a pretty easy job, if you have access to a lift.
Start by removing the two clamps that connect the mid/back exhaust to the downpipe. Make sure you have something in place to support the lower section when it drops so you don’t put stress on the other brackets.
Once the sections are separated, you’ll have access to the secondary cats which is a foot from the entrance of the pipe. (See attached pic)
Tools you’ll need:
Long crowbar
Hammer
Flashlight
(Optional but helpful) scope camera to check your work. I have a Milwaukee M12 Spector 360.
Use the crowbar and hammer to carefully chisel out the OPF filter. Take your time to make sure you remove everything — that’s where the scope camera comes in handy.
That’s it. The whole process took me about an hour.
Thanks u so much. Do prefacelift 2018s have these too? Also in some of ur pics it looks like u replaced piping. Are there 2 secondary cats? Did I get them or replace with piping?
