Long Tube Headers for 1999-2006 Chevy/GMC Silverado/Avalanche/Sierra 1500 4.8L/5.3L/6.0L with Optional Cold Air Intake

Sharing from @ErikRose: LONGTUBE HEADERS ON THE CAMMED SILVERADO 5.3L SOUNDS LIKE A NASCAR

🎥Installation Video

Flashark Long Tube Headers for 1999-2006 Chevy/GMC Silverado/Avalanche/Sierra 1500 4.8L/5.3L/6.0L with Optional Cold Air Intake

FLASHARK Long Tube Headers are designed specifically for 1999-2006 Chevy/GMC 1500 models with 4.8L, 5.3L, and 6.0L engines. These headers improve exhaust flow, delivering a 10-15 horsepower and torque boost, optimizing acceleration and overall engine performance. Crafted from high-quality stainless steel with TIG-welded CNC-machined flanges, they offer durability and a perfect fit. The 3" Y-pipe ensures improved exhaust efficiency, delivering a more aggressive sound.

Vehicle Fitment:

• 1999-2006 Chevrolet Silverado 1500 (2WD) 4.8L, 5.3L, 6.0L
• 1999-2006 GMC Sierra 1500 (2WD) 4.8L, 5.3L, 6.0L
  
• 2002-2006 Chevrolet Avalanche 1500 (2WD) 4.8L, 5.3L, 6.0L

Perfectly designed long tube headers to enhance your truck's performance, with optimized fitment for 4.8L, 5.3L, 6.0L engines in 1999-2006 models.

Note: If using a larger 4L80E transmission the bellhousing ears may need to be trimmed for proper clearance.
Note: Earlier 2500s might have fitment issues due to chassis being designed from previous years.

Specifications:

Brand Name: FLASHARK
Certificate: ISO9001:2000
Placement on Vehicle: Front
Color: Black, Silver
Surface: Mirror Polish
Header Inlet/Outlet Size (IN):1.83" / 2.84"
2 x 4-1 manifolds connecting into a 3" Y-pipe
TIG welded CNC machined flange
Bolt-on installation
Professional Installation is Highly Recommended
Model: EH28917(ES08207) EH28903(ES08356)
Application: Automobile Exhaust Header

If you like 1999-2006 4.8L, 5.3L, 6.0L Long Tube Headers, please feel free to buy it; after purchasing, you can always contact us for a full refund if you don't want it;

Purchase instructions: professional installation is highly recommended, and while most of the time these exhaust systems work perfectly together, occasionally a slight modification to the exhaust system is required to achieve the perfect fit.

Features:

1.100% Brand new, never been used.
2. Made of high quality T-201 or T-304 or T-409 stainless steel.( According you requirements)
3. TIG welded CNC machine flan
4. Increase high flow air, instantly gain 10 to 15 Hp. / Tq.
5. Improve Sound, Horsepower & Torque
6. Mandrel-Bent For Maximum Performance
7. TIG Weld & Polished Stainless Steelge.
8. Polished finish surface.
9. Direct bolt-on, no modification needed.
10. High-quality aftermarket parts.
11. Professional workmanship.
12. Strict quality control during the process.
13. The item is the same as the picture shown.
14. All necessary hardware, bolts, and gaskets

These long tube headers are engineered for durability and performance, ensuring your 1999-2006 4.8L, 5.3L, and 6.0L engines operate at their peak. With our headers, you can expect a noticeable improvement in exhaust flow, enhanced engine sound, and increased horsepower. 

Packing List:

1 x set of header exhaust with Y-pipe
Just as the pictures shown

Delivery:

Free Shipping; 
Shipping Time: Estimated in 3-5 Working Days

NOTE:

(1)It would be highly appreciated if you might contact us first once you have any problems concerning the items. And you can expect all the issues would be resolved ASAP!
(2)Please let us know before you send us the neutral/negative feedback that wont help to finish the issues. And I will try my best to provide the best solutions which would meet our satisfactory!

Boost Your Truck’s Performance and Sound

Maximize Engine Power
Flashark Long Tube Headers unlock extra horsepower and torque by improving exhaust flow. You’ll gain 10–15 HP and torque, giving your Silverado, Sierra, or Avalanche quicker acceleration, stronger mid-range performance, and a noticeable boost while towing or hauling.

Aggressive, Sporty Exhaust Tone
Tailored for your 4.8L, 5.3L, or 6.0L engine, these headers create a deeper, richer sound that complements your truck’s performance. Expect a sporty growl at higher RPMs, turning heads without being overpowering.

Smooth, Efficient Engine Operation
By reducing exhaust restrictions, these headers let your engine breathe better, improving throttle response and overall efficiency. Enjoy smoother acceleration and optimized performance every time you drive.

Comparison with Stock Exhaust Manifolds

When upgrading your 1999–2006 Silverado, Sierra, or Avalanche with 4.8L, 5.3L, or 6.0L engines, it’s important to know how Flashark Long Tube Headers outperform the stock (OEM) exhaust manifolds:

• Exhaust Flow: OEM manifolds are compact and designed for quiet operation, which can restrict exhaust flow. Flashark long tube headers open up the exhaust path, reducing bottlenecks and improving engine efficiency.
• Performance Gains: Stock manifolds provide baseline power, while Flashark headers typically add 10–15 HP and torque by allowing the engine to breathe better.
• Sound Characteristics: OEM manifolds keep your truck quiet, but Flashark headers deliver a deeper, more aggressive tone that enhances the driving experience.
• Durability and Material: Stock manifolds are usually cast iron and prone to cracking under high stress or heat. Flashark headers are made from high-quality stainless steel (T201, T304, or T409), offering superior corrosion resistance, longevity, and a polished finish.

About the Chevy 4.8L/5.3L/6.0L V8 Engines

GM’s 4.8L, 5.3L, and 6.0L V8 engines—commonly found in Silverado, Sierra, Tahoe, Suburban, and other full-size trucks—share the same LS-based architecture, which means they respond similarly to exhaust upgrades. The 5.3L is the most widely used version and is known for solid low-end torque, but all three engines suffer from restrictive factory manifolds that limit airflow. Installing long tube headers significantly improves exhaust scavenging, reduces backpressure, and delivers noticeable gains in horsepower, throttle response, and sound. Our headers are engineered to fit all three engine sizes across compatible GM truck/SUV model years, offering a reliable performance upgrade whether your vehicle runs a 4.8L, 5.3L, or 6.0L setup.

FAQ

1. Will these headers fit my 1999–2006 Silverado/Sierra 1500?

Yes — these long tube headers fit 1999–2006 Chevy/GMC Silverado and Sierra 1500 2WD models with 4.8L, 5.3L, and 6.0L engines.
Note: Some early 2500 models may have clearance issues due to older chassis design.

2. Do these headers work with 4WD models?

Fitment is designed for 2WD models.
Some customers have installed them on 4WD, but minor modification may be required.
Professional installation is strongly recommended.

3. Do I need a tune after installing these long tube headers?

A tune is not required for basic fitment, but:

• A tune is recommended to maximize horsepower gains.
• A tune may be required to avoid check engine lights depending on your O2 sensor configuration and local emissions requirements.

4. Will these work with a 4L80E transmission?

Yes, but when using a larger 4L80E transmission, the bellhousing ears may need to be trimmed for proper clearance.

5. Will these headers cause clearance issues?

Only in two situations:

• Early 2500 models.
• 4L80E transmission without trimming.

Otherwise, normal 1500 2WD models do not have clearance issues.

6. Do these headers require cutting or welding?

In most cases, these headers and Y-pipe bolt on directly.
However, depending on your existing exhaust setup, a slight modification to the exhaust system may be required for the perfect fit.

7. Do these headers improve horsepower?

Yes. Customers typically gain 10–15 HP and torque thanks to improved exhaust flow.

8. Are these headers made from T201, T304, or T409 stainless steel?

We offer multiple stainless steel options depending on your requirements:

• T201 (standard).
• T304 (premium, best corrosion resistance).
• T409 (high strength, performance-focused).

9. Does this kit come with hardware and gaskets?

Yes — all necessary hardware, bolts, and gaskets are included in the package.

10. Will these change the sound of my truck?

Yes. You can expect:

• A deeper, more aggressive tone.
• Faster throttle response.
• Stronger mid–high RPM power.