The main and additional mufflers together with the pipes are a non-separable unit. However, separate parts of the exhaust system are available for sale (main or additional muffler). They can be replaced by cutting off the damaged part and installing a new one using special connecting clamps.
To remove the main and additional mufflers as an assembly, do the following.
1. Remove the rear suspension beam "Removal and installation the rear suspension beam").
2. Unscrew the two nuts securing the flange of the inlet pipe to the flange of the additional muffler.
3. Slide the additional airbag cushions off the exhaust system brackets...
4. ...and the main mufflers.
5. Disconnect the flanges of the inlet pipe and the additional muffler...
6. ...and remove the main and additional mufflers together with the pipes.
7. Remove the sealing gasket from the intake pipe studs.
NOTE: Replace the flange sealing gasket each time the connection is disassembled.
8. Install new mufflers in the reverse order of removal. To make it easier to install the cushions on the muffler brackets and body, lubricate the cushions with a soap solution.
To replace the main or additional muffler, cut the connecting pipe of the main and additional mufflers at the place indicated by the marks.
NOTE: This is what the marks on the connecting pipe of the main and additional mufflers look like.
After installing the new muffler, connect the pipes using the supplied special clamp.
(The source of the article is available on the website CHEVYMAN.ru)