
This exhaust system isn’t called “Monster” just to sound cool. That’s because the Banks’ Monster® Exhaust is a meticulously designed & tested system that actually delivers cooler exhaust gas temperatures. Cooler EGT equals power. This 4" rugged, heavy-duty 100% stainless steel Monster of an exhaust system cuts backpressure by up to 98% — that’s almost NO backpressure! With air-flows up to 176% better than your Duramax’s stock exhaust, Banks Monster exhaust system is streamlined with heavy-wall tubing and constant-diameter bends — maximizing your truck’s airflow.
Key Features
- Extensively tested & validated
- Improves flow up to 176% — virtually no backpressure
- 100% stainless steel — no aluminum here!
- Giant 5" polished rolled-edge tip
- Muffler’s expansion chamber cuts obnoxious noise
- Mandrel-bent Head Pipe Assembly (Non-catalytic Converter Vehicles Only)
- Won’t void factory warranty
- Lifetime Limited Warranty

With a name like Monster you might think the Banks Monster exhaust system obnoxiously over-powers in-cab conversations and music — not so. Unlike the noisy drone of many straight-through mufflers, this Monster’s muffler is extensively sound-tested and engineered with a unique expansion chamber and spun ceramic, a very high-temperature packing. The result? A rich, authoritative exhaust note that isn’t domineering — yet it nearly triples the stock muffler’s flow! Now that’s a Monster!

How would you finish off this expertly engineered Monster? Banks has crowned their Monster exhaust system with a 5" rolled edged tailpipe of polished-stainless steel. It’s double-walled design features a 1/2" air gap — preventing heat from tarnishing its mirror finish. This Monster’s crown adjusts with a clamp, letting you decide its position on the tailpipe. All considered, the 4" Banks’ Monster is one cool exhaust system.

Banks Monster Exhaust will fit GMC/Chevy Silverado/Sierra 2500HD & 3500HD trucks:
Trucks without Catalytic Converters
| Part # | Engine & Body Style | |
| 48628 | 2001–2004 GMC/Chevy Duramax 6.6L LB7 Standard Cab, Long Bed | |
| 48629 | 2001–2004 GMC/Chevy Duramax 6.6L LB7 Extended or Crew Cab, Short Bed | |
| 48630 | 2001–2004 GMC/Chevy Duramax 6.6L LB7 Extended or Crew Cab, Long Bed |
Trucks with Catalytic Converters
| Part # | Engine & Body Style | |
| 48632 | 2002–2005 GMC/Chevy Duramax 6.6L LB7/LLY Standard Cab, Long Bed | |
| 48633 | 2002–2004 GMC/Chevy Duramax 6.6L LB7/LLY Extended/Crew Cab, Short Bed | |
| 48634 | 2001–2004 GMC/Chevy Duramax 6.6L LB7/LLY Extended/Crew Cab, Long Bed |

Links
- Manufacturer Product Web Pages
- Product Installation Manual
- Manufacturer Product Support
- Manufacturer Warranty
Manufacturer Contact Info:
800-601-8072
Gale Banks Engineering
546 S. Duggan Avenue
Azusa, CA 91702









