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2021 Silverado single exhaust to dual exhaust conversion

Steven Vona
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Steven Vona Enthusiast

Steven Vona

Posted
Posted (edited)

I bought a 2021 RST and it came with the single exhaust.  I really liked the look of the dual exhaust bumpers so I went on ebay and purchased one.  I had the tips powder coated black and a local muffler shop redirect the single exhaust out of the right exhaust port.

 

 

It's bothering me.. I want to swap out the pipes now for the factory dual exhaust.  From what I can see I need:

 

1) Driver side exhaust hanger

2) Driver side spare tire exhaust heat shield

3) y pipe from muffler and tail pipes

 

I called the dealer near me and asked for some part numbers and it was like I was asking for a kidney.  I guess they are too busy to help me.  

 

I was wondering has anyone done anything like this here?  I was hoping someone did and can share their experience and part numbers.  Or if anyone removed their factory pipes I would be more than willing to buy them. Unfortunately I don't post enough to use the for sale / wanted forum.

 

Any help is appreciated.  Thanks.

bumper2.jpg

Edited by Steven Vona
Silverado4x4 Senior Enthusiast

Silverado4x4

Posted
Posted (edited)
39 minutes ago, Steven Vona said:

I bought a 2021 RST and it came with the single exhaust.  I really liked the look of the dual exhaust bumpers so I went on ebay and purchased one.  I had the tips powder coated black and a local muffler shop redirect the single exhaust out of the right exhaust port.

 

 

It's bothering me.. I want to swap out the pipes now for the factory dual exhaust.  From what I can see I need:

 

1) Driver side exhaust hanger

2) Driver side spare tire exhaust heat shield

3) y pipe from muffler and tail pipes

 

I called the dealer near me and asked for some part numbers and it was like I was asking for a kidney.  I guess they are too busy to help me.  

 

I was wondering has anyone done anything like this here?  I was hoping someone did and can share their experience and part numbers.  Or if anyone removed their factory pipes I would be more than willing to buy them. Unfortunately I don't post enough to use the for sale / wanted forum.

 

Any help is appreciated.  Thanks.

bumper2.jpg

Contact newdude on here he works at a Chevrolet dealership and can get you all the part numbers you need or go to a exhaust shop and they will fix you up on the dual tail pipes, going to an exhaust shop will be alot cheaper then buying the parts . They will just cut the exhaust pipe behind the muffler and "Y" it out then run the pipes to both sides of the bumper and make sure you bring them the exhaust tips to line them up or put them on before you go. If you do it this way make sure they do a true "Y" pipe and not just tap into the pipe because when you start it up when cold one side of the pipe will blow heavy steam out and very little if any on the pipe that was tapped. Thats what I would do.

Edited by Silverado4x4
Gangly Senior Enthusiast

Gangly

Posted
Posted

I agree with the above.  It might be much cheaper and simpler to have an exhaust shop fab up a y-pipe and run the exhaust to the rear for you.  Either way, its simple enough but I would definitely get the part number for the exhaust hangers.

JANDJMAM New Member

JANDJMAM

Posted
Posted

I may be confused but i thought the 2021 RST with Z71 came with dual pipe out the back bumper. I have seen

just one tip on some but not many!

Steven Vona Enthusiast

Steven Vona

Posted
  • Author
Posted

Can anyone recommend a reliable exhaust shop in South Jersey or Philadelphia area? 

newdude Senior Enthusiast

newdude

Posted
Posted
On 4/2/2022 at 4:49 PM, Steven Vona said:

I bought a 2021 RST and it came with the single exhaust.  I really liked the look of the dual exhaust bumpers so I went on ebay and purchased one.  I had the tips powder coated black and a local muffler shop redirect the single exhaust out of the right exhaust port.

 

 

It's bothering me.. I want to swap out the pipes now for the factory dual exhaust.  From what I can see I need:

 

1) Driver side exhaust hanger

2) Driver side spare tire exhaust heat shield

3) y pipe from muffler and tail pipes

 

I called the dealer near me and asked for some part numbers and it was like I was asking for a kidney.  I guess they are too busy to help me.  

 

I was wondering has anyone done anything like this here?  I was hoping someone did and can share their experience and part numbers.  Or if anyone removed their factory pipes I would be more than willing to buy them. Unfortunately I don't post enough to use the for sale / wanted forum.

 

Any help is appreciated.  Thanks.

 

 

 

You'd need the entire exhaust, not just the hangers, if you wanted to do it exactly like factory.  Factory dual doesn't use that rubber hanger that the single exit uses at all, has two hangers left and right out back near the bumper area.  They bolt to the frame.  

 

And for the price of the OE dual exit hangers, have the shop do it with some hangers they have, and have them route the pipe to the outlets.  Would be much cheaper.  

  • 4 weeks later...
Steven Vona Enthusiast

Steven Vona

Posted
  • Author
Posted

Thanks for the input. After talking to many people and doing a lot of research I decided to buy the Borla touring exhaust and ordered some factory hangers from gmpartsdirect.  I have everything I need except one item.

 

I need the heat shield that protects the spare tire from both sides.  Right now the heat shield I have only covers the passenger side of the spare tire.  I have searched, talked to the dealer where I bought my truck, etc..  Nobody can get me the part number for this heat shield.  I was hoping @newdudecan help.  Picture included because nobody seems to know what I am talking about.

2019-Silverado-Undercarriage-Exhaust-shield.jpg

Diamond817 Enthusiast

Diamond817

Posted
Posted (edited)

Ok ,hold on. I did this same exact mod. First off, you don't need the heat shield. Second, go on craigslist or FB marketplace and find the oem dual exhaust for your truck (5.3 & 6.2 use different size exhaust). I paid $200 for the OEM dual exhaust from the cat back on marketplace. Third, just go to GMpartsdirect and look up exhaust parts for the 2020 Silverado 1500 and you will find the exhaust hangers for right and left with bolts. Done. Easy peasy. 

 

 

Edit. Never mind, I just saw you went with aftermarket. You can still look up part numbers on GMpartsdirect or the like.

 

 

-

Edited by Diamond817
  • Like 1
newdude Senior Enthusiast

newdude

Posted
Posted (edited)
11 hours ago, Steven Vona said:

Thanks for the input. After talking to many people and doing a lot of research I decided to buy the Borla touring exhaust and ordered some factory hangers from gmpartsdirect.  I have everything I need except one item.

 

I need the heat shield that protects the spare tire from both sides.  Right now the heat shield I have only covers the passenger side of the spare tire.  I have searched, talked to the dealer where I bought my truck, etc..  Nobody can get me the part number for this heat shield.  I was hoping @newdudecan help.  Picture included because nobody seems to know what I am talking about.

2019-Silverado-Undercarriage-Exhaust-shield.jpg

 

 

Dual exhaust heat shield is 84535834.  This will replace the one you have in your truck entirely.  The dual exhaust shield is a one piece half moon shape if you will, not two individuals.  You might need one of 11602085 nut and 3 of 11611334.    

Edited by newdude
Steven Vona Enthusiast

Steven Vona

Posted
  • Author
Posted (edited)

Thanks a million @newdude.  However that part (84535834) says driver side heat shield.  I just want to make sure I understood you correctly.  From the description (and the photo) it sounds like it's for the driver side, not replacing the whole thing and covering both sides.  Again, I really appreciate your help.  I just want to make sure I am getting the correct thing.

Screenshot from 2022-05-04 12-39-54.png

Edited by Steven Vona
newdude Senior Enthusiast

newdude

Posted
Posted
3 hours ago, Steven Vona said:

Thanks a million @newdude.  However that part (84535834) says driver side heat shield.  I just want to make sure I understood you correctly.  From the description (and the photo) it sounds like it's for the driver side, not replacing the whole thing and covering both sides.  Again, I really appreciate your help.  I just want to make sure I am getting the correct thing.

 

 

 

 

Yea, its just labeled weird.  Its a one piece shield.  Here is the actual illustration GM has.  

 

shield.png.6cf073646572ec88332d699f29664f0b.png

Diamond817 Enthusiast

Diamond817

Posted
Posted (edited)
3 hours ago, Steven Vona said:

@diamond817 You dont think the heat shield is necessary?  

I have had my dual exhaust installed without the heat shield for 22k miles so far and no issues with the spare tire. I actually removed the driver side heat shield also. And I have resonators that emit heat towards the tire, whereas the aftermarket Borla doesn't. I wouldn't worry about it too much. The exhaust just doesn't get that hot back there.

 

 

 

-

IMG_20220504_190529654.jpg

IMG_20220504_190533442.jpg

Edited by Diamond817
  • Like 1

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