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Kenworth T660 Exhaust Parts

  • Product
  • Qty in Cart
  • Quantity
  • Price
  • Subtotal
  • 4 ID X 72 Inch Chrome-Plated Steel Flat Top Stack By BESTfit

    4 ID X 72 Inch Chrome-Plated Steel Flat Top Stack By BESTfit

    BESTFIT TRUCK PARTS

    $305.99
    BESTfit 4 Inch I.D. Inlet X 72 Inch Chrome-Plated Steel Flat Top StackDiscover the perfect blend of functionality and elegance with the BESTfit 4 Inch I.D. Inlet X 72 Inch Chrome-Plated Steel Flat...
    09-080100256
    SKU:
    09-080100256
    Truck Class:
    Universal
    Length Options:
    72 Inch
    Style Options:
    Flat Top
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Diameter Options:
    4 Inch
    Product Type:
    Exhaust
    $305.99
    Qty in Cart: 0
    Price:
    $305.99
    Subtotal:
  • 4 OD X 48 Inch Chrome-Plated Steel Flat Top Stack By BESTfit

    4 OD X 48 Inch Chrome-Plated Steel Flat Top Stack By BESTfit

    BESTFIT TRUCK PARTS

    $190.99
    BESTfit 4 Inch O.D. Inlet X 48 Inch Chrome-Plated Steel Flat Top StackGive your vehicle an instant upgrade with the BESTfit 4 Inch O.D. Inlet X 48 Inch Chrome-Plated Steel Flat Top Stack, expertly...
    09-080100254
    SKU:
    09-080100254
    Truck Class:
    Universal
    Diameter Options:
    4 Inch
    Length Options:
    48 Inch
    Style Options:
    Flat Top
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Product Type:
    Exhaust
    $190.99
    Qty in Cart: 0
    Price:
    $190.99
    Subtotal:
  • 4 OD X 24 Inch Chrome-Plated Steel Flat Top Stack by BESTfit

    4 OD X 24 Inch Chrome-Plated Steel Flat Top Stack by BESTfit

    BESTFIT TRUCK PARTS

    $136.99
    BESTfit 4 Inch O.D. Inlet X 24 Inch Chrome-Plated Steel Flat Top StackMake your truck stand out with the BESTfit 4 Inch O.D. Inlet X 24 Inch Chrome-Plated Steel Flat Top Stack. Made from high-quality...
    09-080100251
    SKU:
    09-080100251
    Truck Class:
    Universal
    Diameter Options:
    4 Inch
    Length Options:
    24 Inch
    Style Options:
    Flat Top
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Product Type:
    Exhaust
    $136.99
    Qty in Cart: 0
    Price:
    $136.99
    Subtotal:
  • 5 ID X 72 Inch Chrome-Plated Steel Miter Cut Stack by BESTfit

    5 ID X 72 Inch Chrome-Plated Steel Miter Cut Stack by BESTfit

    BESTFIT TRUCK PARTS

    $452.99
    BESTfit 5 Inch ID Inlet X 72 Inch Chrome-Plated Steel Miter Cut StackElevate your truck's exhaust system with the BESTfit 5 Inch ID Inlet X 72 Inch Chrome-Plated Steel Miter Cut Stack. Constructed...
    09-080100246
    SKU:
    09-080100246
    Truck Class:
    Universal
    Diameter Options:
    5 Inch
    Length Options:
    72 Inch
    Style Options:
    Miter Cut
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Product Type:
    Exhaust
    $452.99
    Qty in Cart: 0
    Price:
    $452.99
    Subtotal:
  • 4 OD X 72 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    4 OD X 72 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    BESTFIT TRUCK PARTS

    $319.99
    BESTfit 4 Inch O.D. Inlet X 72 Inch Chrome-Plated Steel Curved Top StackMake your truck's exhaust system a work of art with the BESTfit 4 Inch O.D. Inlet X 72 Inch Chrome-Plated Steel Curved Top...
    09-080100236
    SKU:
    09-080100236
    Truck Class:
    Universal
    Diameter Options:
    4 Inch
    Length Options:
    72 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Style Options:
    Curve Turn
    Product Type:
    Exhaust
    $319.99
    Qty in Cart: 0
    Price:
    $319.99
    Subtotal:
  • 4 ID X 72 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    4 ID X 72 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    BESTFIT TRUCK PARTS

    $354.99
    BESTfit 4 Inch ID Inlet X 72 Inch Chrome-Plated Steel Curved Top StackUpgrade your exhaust system with the BESTfit 4 Inch ID Inlet X 72 Inch Chrome-Plated Steel Curved Top Stack ? perfect for those...
    09-080100235
    SKU:
    09-080100235
    Truck Class:
    Universal
    Diameter Options:
    4 Inch
    Length Options:
    72 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Style Options:
    Curve Turn
    Product Type:
    Exhaust
    $354.99
    Qty in Cart: 0
    Price:
    $354.99
    Subtotal:
  • 4 ID X 60 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    4 ID X 60 Inch Chrome-Plated Steel Curved Top Stack By BESTfit

    BESTFIT TRUCK PARTS

    $310.99
    BESTfit 4 Inch ID Inlet X 60 Inch Chrome-Plated Steel Curved Top StackTransform your vehicle's exhaust system with the BESTfit 4 Inch ID Inlet X 60 Inch Chrome-Plated Steel Curved Top Stack, a...
    09-080100234
    SKU:
    09-080100234
    Diameter Options:
    4 Inch
    Truck Class:
    Universal
    Length Options:
    60 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Style Options:
    Curve Turn
    Product Type:
    Exhaust
    $310.99
    Qty in Cart: 0
    Price:
    $310.99
    Subtotal:
  • 3 OD X 24 Inch Chrome-Plated Steel Curved Top Stack by BESTfit

    3 OD X 24 Inch Chrome-Plated Steel Curved Top Stack by BESTfit

    BESTFIT TRUCK PARTS

    $139.99
    BESTfit 3 Inch O.D. Inlet X 24 Inch Chrome-Plated Steel Curved Top Stack* High Quality Stack* Chrome-Plated Steel* Dimensions  - 3 Inch Diameter  - 24 Inch Length* Curved Top* Hardware Not Included*...
    09-080100222
    SKU:
    09-080100222
    Truck Class:
    Universal
    Diameter Options:
    3 Inch
    Length Options:
    24 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Style Options:
    Curve Turn
    Product Type:
    Exhaust
    $139.99
    Qty in Cart: 0
    Price:
    $139.99
    Subtotal:
  • BESTfit 4 X 16 X 10.5 Inch Aluminized Steel Universal Type B Y-Pipe

    BESTfit 4 X 16 X 10.5 Inch Aluminized Steel Universal Type B Y-Pipe

    BESTFIT TRUCK PARTS

    $216.99
    BESTfit 4 X 16 X 10.5 Inch Aluminized Steel Universal Type B Y-PipeDiscover the benefits of upgrading with the BESTfit 4 X 16 X 10.5 Inch Aluminized Steel Universal Type B Y-Pipe. This high-quality,...
    09-080100210
    SKU:
    09-080100210
    Diameter Options:
    4 Inch
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Style Options:
    Y-Pipe
    Truck Class:
    Heavy Duty
    Product Type:
    Exhaust
    $216.99
    Qty in Cart: 0
    Price:
    $216.99
    Subtotal:
  • BESTfit 5 X 14 X 25 Inch Chrome-Plated Steel Universal Type A Y-Pipe With Divider Plate

    BESTfit 5 X 14 X 25 Inch Chrome-Plated Steel Universal Type A Y-Pipe With Divider Plate

    BESTFIT TRUCK PARTS

    $460.99
    BESTfit 5 X 14 X 25 Inch Chrome-Plated Steel Universal Type A Y-Pipe With Divider Plate* High Quality Y Pipe* Chrome-Plated Steel* Y Shaped* Dimensions  - 5 Inch Diameter  - 25 Inch Width  - 14 Inch...
    09-080100207
    SKU:
    09-080100207
    Diameter Options:
    5 Inch
    Truck Class:
    Universal
    Material Options:
    Steel
    Make:
    Universal Items
    Finish Options:
    Chrome-Plated
    Style Options:
    Y-Pipe
    Product Type:
    Exhaust
    $460.99
    Qty in Cart: 0
    Price:
    $460.99
    Subtotal:
  • BESTfit 5 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 5.88 Inch OD For Cummins N14/ISX/3406/C15

    BESTfit 5 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 5.88 Inch OD For Cummins N14/ISX/3406/C15

    BESTFIT TRUCK PARTS

    $56.99
    BESTfit 5 Inch I.D. X 2 Inch OAL Steel Replacement Turbo Flange With 5.88 Inch O.D. Fits Cummins N14/ISX/3406/C15Get your exhaust back to working great with this high quality, style D repair flange...
    09-080100201
    SKU:
    09-080100201
    Diameter Options:
    5 Inch
    Truck Class:
    Universal
    Length Options:
    2 Inch
    Style Options:
    Cummins
    Material Options:
    Steel
    Make:
    Universal Items
    Product Type:
    Exhaust
    $56.99
    Qty in Cart: 0
    Price:
    $56.99
    Subtotal:
  • BESTfit 4 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 4.75 Inch OD For Cummins L10/3176

    BESTfit 4 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 4.75 Inch OD For Cummins L10/3176

    BESTFIT TRUCK PARTS

    $61.99
    BESTfit 4 Inch I.D. X 2 Inch OAL Steel Replacement Turbo Flange With 4.75 Inch O.D. Fits Cummins L10/3176Get the perfect fit on a 9N-6325 engine with this quality style D repair flange. It is made of...
    09-080100200
    SKU:
    09-080100200
    Diameter Options:
    4 Inch
    Truck Class:
    Universal
    Length Options:
    2 Inch
    Style Options:
    Cummins
    Material Options:
    Steel
    Make:
    Universal Items
    Product Type:
    Exhaust
    $61.99
    Qty in Cart: 0
    Price:
    $61.99
    Subtotal:
  • BESTfit 4 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 4.625 Inch OD For CAT 9N-6325

    BESTfit 4 Inch ID X 2 Inch OAL Steel Replacement Turbo Flange With 4.625 Inch OD For CAT 9N-6325

    BESTFIT TRUCK PARTS

    $73.99
    BESTfit 4 Inch I.D. X 2 Inch OAL Steel Replacement Turbo Flange With 4.625 Inch O.D. Fits CAT 9N-6325Get the perfect fit for your Cat Engine with this quality style D manifold outlet. It is made of a...
    09-080100199
    SKU:
    09-080100199
    Diameter Options:
    4 5/8 Inch
    Truck Class:
    Universal
    Length Options:
    2 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Product Type:
    Exhaust
    $73.99
    Qty in Cart: 0
    Price:
    $73.99
    Subtotal:
  • 5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 5.5 Inch Diameter Flange For CAT 3406/C15

    5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 5.5 Inch Diameter Flange For CAT 3406/C15

    AUTOMANN USA

    $31.15
    5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo PipeEnhance the turbo performance of your Caterpillar 3406 or C15 with the 5 Inch ID-OD X 6 Inch OAL Type A Turbo Pipe, featuring a 5.88-inch...
    09-080100198
    SKU:
    09-080100198
    Diameter Options:
    5 Inch
    Length Options:
    6 Inch
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Truck Class:
    Heavy Duty
    Product Type:
    Exhaust
    Ready To Ship:
    Yes
    $31.15
    Qty in Cart: 0
    Price:
    $31.15
    Subtotal:
  • 5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 5.5 Inch Diameter Flange For Cummins ISX/N14

    5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 5.5 Inch Diameter Flange For Cummins ISX/N14

    AUTOMANN USA

    $29.93
    5 Inch ID-OD X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 5.5 Inch Diameter Flange Fits Cummins ISX/N14Optimize your Cummins ISX or N14's exhaust system with the Aluminized Steel Type A Turbo...
    09-080100197
    SKU:
    09-080100197
    Diameter Options:
    5 Inch
    Length Options:
    6 Inch
    Style Options:
    Cummins
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Truck Class:
    Heavy Duty
    Product Type:
    Exhaust
    Ready To Ship:
    Yes
    $29.93
    Qty in Cart: 0
    Price:
    $29.93
    Subtotal:
  • BESTfit 5.25 Inch Machined Turbo Flare For Detroit Diesel Turbo 6V/8V92T

    BESTfit 5.25 Inch Machined Turbo Flare For Detroit Diesel Turbo 6V/8V92T

    BESTFIT TRUCK PARTS

    $272.99
    BESTfit Aluminized Steel Type A Turbo Pipe With FlangeRedefine your Detroit engine with the BESTfit 5 Inch ID-O.D. X 4 Inch OAL Aluminized Steel Type A Turbo Pipe from 4 State Trucks. This turbo...
    09-080100196
    SKU:
    09-080100196
    Diameter Options:
    5 Inch
    Length Options:
    4 Inch
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Truck Class:
    Heavy Duty
    Product Type:
    Exhaust
    $272.99
    Qty in Cart: 0
    Price:
    $272.99
    Subtotal:
  • BESTfit 4 ID/OD X 6 Inch Aluminized Turbo Outlet Adapter With Flange For Detroit 671/12V71

    BESTfit 4 ID/OD X 6 Inch Aluminized Turbo Outlet Adapter With Flange For Detroit 671/12V71

    BESTFIT TRUCK PARTS

    $31.83
    BESTfit 4.75 Inch Turbo Flare Lip for Detroit Diesel 671/12V71Get the perfect fit for your Detroit Diesel 12V71 Turbo with this quality style C manifold outlet. It is made of a rust and corrosion...
    09-080100195
    SKU:
    09-080100195
    Diameter Options:
    4 Inch
    Truck Class:
    Universal
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Length Options:
    6 Inch
    Product Type:
    Exhaust
    $31.83
    Qty in Cart: 0
    Price:
    $31.83
    Subtotal:
  • BESTfit 4 ID/OD X 4 Inch Aluminized Turbo Outlet Adapter With Flange Style A For L10 Cummins

    BESTfit 4 ID/OD X 4 Inch Aluminized Turbo Outlet Adapter With Flange Style A For L10 Cummins

    BESTFIT TRUCK PARTS

    $31.83
    BESTfit 4 Inch ID-OD X 4 Inch OAL Aluminized Steel Type A Turbo Pipe* High Quality Turbo Manifold Outlet* Style A* Highly Corrosion Resistant* Made Of Durable And Strong Aluminized Steel* 4 Inch...
    09-080100194
    SKU:
    09-080100194
    Diameter Options:
    4 Inch
    Truck Class:
    Universal
    Style Options:
    Cummins
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Length Options:
    4 Inch
    Product Type:
    Exhaust
    Ready To Ship:
    Yes
    $31.83
    Qty in Cart: 0
    Price:
    $31.83
    Subtotal:
  • BESTfit 4 ID/OD X 4 Inch Aluminized Turbo Outlet Adapter With Flange Style A For CAT 3306

    BESTfit 4 ID/OD X 4 Inch Aluminized Turbo Outlet Adapter With Flange Style A For CAT 3306

    BESTFIT TRUCK PARTS

    $32.89
    BESTfit 4 Inch ID-OD X 4 Inch OAL Aluminized Steel Type A Turbo Pipe* High Quality Turbo Manifold Outlet* Style A* Highly Corrosion Resistant* Made Of Durable And Strong Aluminized Steel* 4 Inch...
    09-080100193
    SKU:
    09-080100193
    Diameter Options:
    4 Inch
    Truck Class:
    Heavy Duty
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Length Options:
    4 Inch
    Product Type:
    Exhaust
    $32.89
    Qty in Cart: 0
    Price:
    $32.89
    Subtotal:
  • BESTfit 4 ID/OD X 6 Inch Inch Aluminized Turbo Outlet Adapter With Flange Style A For Cummins

    BESTfit 4 ID/OD X 6 Inch Inch Aluminized Turbo Outlet Adapter With Flange Style A For Cummins

    BESTFIT TRUCK PARTS

    $38.20
    BESTfit 4 Inch I.D.-O.D. X 6 Inch OAL Aluminized Steel Type A Turbo Pipe With 4.5 Inch Diameter Flange Fits CumminsGet the perfect fit for your Cummins Engine with this quality type A manifold outlet...
    09-080100192
    SKU:
    09-080100192
    Truck Class:
    Universal
    Diameter Options:
    4 Inch
    Style Options:
    Cummins
    Material Options:
    Aluminized Steel
    Make:
    Universal Items
    Length Options:
    6 Inch
    Product Type:
    Exhaust
    $38.20
    Qty in Cart: 0
    Price:
    $38.20
    Subtotal:
  • Total: items /

Adding your products to cart

Your Kenworth T660 is built to work hard—and with the right aftermarket exhaust parts, it can look just as sharp as it performs. Whether you're replacing worn-out components or upgrading for power and style, this lineup has what you need.

Why Customize Your T660 Semi Truck Exhaust System?

- Boost airflow to help your engine breathe easier and run cooler - Enhance fuel efficiency with better exhaust flow and backpressure control - Reduce emissions with DPF and SCR components that keep you compliant - Upgrade your rig’s appearance with polished chrome stacks and custom tips - Improve sound and dial in that deep, smooth tone every driver loves

Get a Full Performance Upgrade

- Chrome Exhaust Stacks & Elbows: Make a bold statement with polished style - Mufflers & DPF Systems: Keep your ride quiet, clean, and road-legal - Piping, Clamps & Mounting Hardware: Built tough for a secure, leak-free setup - Complete Exhaust Kits: Save time with everything you need in one order
No matter your goal, our Kenworth T660 exhaust parts are ready to help you get the job done. Get a full performance upgrade with T660 heating and AC components while you’re enhancing your rig. Shop now and give your T660 the power, efficiency, and polished look it deserves.

Frequently Asked Questions About Kenworth T660 Exhaust Parts

What year models of Kenworth T660 are these exhaust parts compatible with?

Our Kenworth T660 exhaust parts are designed to fit model years 2008-2016. However, compatibility can vary based on your specific engine configuration (Cummins ISX, Caterpillar C15, or Paccar MX). We recommend checking your OEM or calling our technical support team at 1-888-875-7787 to confirm fitment for your specific truck before ordering.

Are these exhaust stacks made from 304 or 409 stainless steel, and what's the difference?

We carry both 304 and 409 stainless steel options. The 409 stainless steel stacks are more budget-friendly and offer good corrosion resistance for most applications. The 304 stainless steel options provide superior corrosion resistance and maintain their polish better over time, making them ideal for show trucks or harsh weather conditions. All chrome-plated options use heavy-duty steel bases with triple-chrome plating for maximum shine and durability.

Do I need special tools or professional installation for these exhaust components?

Most exhaust stack installations can be completed with basic hand tools including wrenches, sockets, and clamps. Typical installation takes 2-4 hours depending on your experience level. For muffler replacements or complete exhaust system overhauls, you may need a reciprocating saw for removal and possibly welding equipment for certain configurations. We provide detailed installation instructions with each product, and our tech support can walk you through any challenges.

What's the difference between curved, straight, and miter cut exhaust stacks?

Straight stacks provide a classic, traditional look and are the easiest to install. Curved stacks angle away from the cab, reducing soot buildup on your truck and trailer while providing better aerodynamics. Miter cut stacks feature an angled top cut that directs exhaust away from the truck at typically 15, 30, or 45-degree angles. Your choice depends on personal preference, local regulations, and whether you frequently haul tall loads that might be affected by exhaust direction.

How do I prevent my new chrome stacks from bluing or discoloring?

Chrome stacks can blue or discolor from extreme heat, especially during heavy loads or extended idling. To minimize this, ensure proper exhaust flow by checking for restrictions in your system. Consider using exhaust wrap on the first 12-18 inches inside the stack where heat is most intense. Regular cleaning with chrome polish and avoiding excessive idling can also help maintain appearance. For trucks that see heavy-duty use, consider our polished stainless options which handle heat discoloration better than chrome.


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