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Kenworth T660 Exhaust Parts

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  • Qty in Cart
  • Quantity
  • Price
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  • BESTfit 2 Inch X 25 Ft Galvanized Steel Flex Hose

    BESTfit 2 Inch X 25 Ft Galvanized Steel Flex Hose

    BESTFIT TRUCK PARTS

    $151.99
    2 Inch X 25 Ft Galvanized Flex Hose By BESTfitKeep your system running smoothly with the BESTfit 2 Inch x 25 Ft Galvanized Steel Flex Hose. This high-quality galvanized metal hose measures 2 inches...
    GR-G15-2300
    SKU:
    GR-G15-2300
    Style Options:
    Standard
    Finish Options:
    Galvanized
    Length Options:
    300 Inch
    Diameter Options:
    2 Inch
    Product Type:
    Exhaust
    Material Options:
    Steel
    Make:
    Universal Items
    $151.99
    Qty in Cart: 0
    Price:
    $151.99
    Subtotal:
  • BESTfit 6 Inch X 10 Ft Galvanized Steel Flex Hose

    BESTfit 6 Inch X 10 Ft Galvanized Steel Flex Hose

    BESTFIT TRUCK PARTS

    $169.99
    6 Inch X 10 Ft Galvanized Flex Hose By BESTfitDepend on the BESTfit 6 Inch x 10 Ft Galvanized Steel Flex Hose for secure, corrosion-resistant connections in heavy-duty applications. Crafted from...
    GR-G15-6120
    SKU:
    GR-G15-6120
    Finish Options:
    Galvanized
    Style Options:
    Standard
    Diameter Options:
    6 Inch
    Length Options:
    120 Inch
    Product Type:
    Exhaust
    Material Options:
    Steel
    Make:
    Universal Items
    $169.99
    Qty in Cart: 0
    Price:
    $169.99
    Subtotal:
  • BESTfit 4 X 12 Inch Galvanized Steel Flex Hose

    BESTfit 4 X 12 Inch Galvanized Steel Flex Hose

    BESTFIT TRUCK PARTS

    $19.29
    4 X 12 Inch Galvanized Flex Hose By BESTfitBuilt for durability and dependable operation, the BESTfit 4 x 12 Inch Galvanized Steel Flex Hose provides corrosion-resistant, flexible performance in a...
    GR-G15-412
    SKU:
    GR-G15-412
    Material Options:
    Steel
    Diameter Options:
    4 Inch
    Product Type:
    Exhaust
    Length Options:
    12 Inch
    Finish Options:
    Galvanized
    Style Options:
    Flex
    Make:
    Universal Items
    $19.29
    Qty in Cart: 0
    Price:
    $19.29
    Subtotal:
  • BESTfit 4 ID X 6 Inch Aluminized Steel Coupler

    BESTfit 4 ID X 6 Inch Aluminized Steel Coupler

    BESTFIT TRUCK PARTS

    $26.99
    4 ID X 6 Inch Aluminized Coupler By BESTfitEnsure long-lasting and secure pipe connections with the BESTfit 4 ID x 6 Inch Aluminized Steel Coupler. Constructed from high-quality 16-gauge aluminized...
    GR-CP-46A
    SKU:
    GR-CP-46A
    Product Type:
    Exhaust
    Make:
    Universal Items
    $26.99
    Qty in Cart: 0
    Price:
    $26.99
    Subtotal:
  • BESTfit 24 Inch 304 Stainless Steel Grab Handle

    BESTfit 24 Inch 304 Stainless Steel Grab Handle

    BESTFIT TRUCK PARTS

    $119.99
    24 Inch Stainless Steel Grab Handle By BESTfit1The BESTfit 24 Inch 304 Stainless Steel Grab Handle is a durable, corrosion-resistant solution for safe and convenient truck access. Made from...
    GR-GH-24S
    SKU:
    GR-GH-24S
    Length Options:
    24 Inch
    Product Type:
    Exhaust
    Material Options:
    Stainless Steel
    Make:
    Universal Items
    $119.99
    Qty in Cart: 0
    Price:
    $119.99
    Subtotal:
  • BESTfit 7-5 Inch I.D. Exhaust Reducer

    BESTfit 7-5 Inch I.D. Exhaust Reducer

    BESTFIT TRUCK PARTS

    $62.99
    7-5 Inch Aluminized Exhaust Reducer By BESTfitMaintain reliable exhaust performance with the BESTfit 7-5 Inch I.D. Exhaust Reducer. Made from durable aluminized steel, it offers an 8-inch height and...
    09-080100601
    SKU:
    09-080100601
    Material Options:
    Aluminum
    Diameter Options:
    7 To 5 Inch
    Product Type:
    Exhaust
    Make:
    Universal Items
    $62.99
    Qty in Cart: 0
    Price:
    $62.99
    Subtotal:
  • BESTfit 6-5 ID X 96 Inch Chrome Curve Top Stack

    BESTfit 6-5 ID X 96 Inch Chrome Curve Top Stack

    BESTFIT TRUCK PARTS

    $695.00
    6-5 ID X 96 Inch Curve Top Stack By BESTfitAchieve smooth and efficient exhaust flow with the BESTfit 6-5 ID x 96 Inch Chrome Curve Top Stack. Made from chrome-plated steel for heavy-duty durability,...
    09-086596172
    SKU:
    09-086596172
    Product Type:
    Exhaust
    Finish Options:
    Chrome-Plated
    Material Options:
    Steel
    Diameter Options:
    6 To 5 Inch
    Height Options:
    96 Inch
    Position:
    Lower
    Style Options:
    Curve Turn
    Make:
    Universal Items
    $695.00
    Qty in Cart: 0
    Price:
    $695.00
    Subtotal:
  • 4-Inch Flex Tubing

    4-Inch Flex Tubing

    AFTERMARKET

    $32.31 - $56.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of Trucks4 X 18 Inch Black Stainless Steel Flex Tubing Replaces SF418, P2065544 X 18 Inch Black 304 Stainless...
    PPR_300364
    SKU:
    PPR_300364
    Length Options:
    18 Inch
    Product Type:
    Exhaust
    Diameter Options:
    4 Inch
    Color:
    Black
    Material Options:
    Stainless Steel
    Length Options:
    24 Inch
    Finish Options:
    Galvanized
    Material Options:
    Steel
    Make:
    Universal Items
    $32.31 - $56.99
    Qty in Cart: 0
    Price:
    $32.31 - $56.99
    Subtotal:
  • BESTfit 3 X 10 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider Plate

    BESTfit 3 X 10 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider Plate

    BESTFIT TRUCK PARTS

    $222.99
    BESTfit 3 X 10 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider PlateKeep the exhaust balanced and exhaust gasses at lower temperatures with this quality Y Pipe. It is constructed...
    09-080100202
    SKU:
    09-080100202
    Product Type:
    Exhaust
    Truck Class:
    Heavy Duty
    Material Options:
    Aluminized Steel
    Diameter Options:
    3 Inch
    Make:
    Universal Items
    $222.99
    Qty in Cart: 0
    Price:
    $222.99
    Subtotal:
  • BESTfit 4 X 12 X 26 Inch Aluminized Steel Universal Type A Y-Pipe With Divider Plate

    BESTfit 4 X 12 X 26 Inch Aluminized Steel Universal Type A Y-Pipe With Divider Plate

    BESTFIT TRUCK PARTS

    $317.99
    BESTfit 4 X 12 X 26 Inch Aluminized Steel Universal Type A Y-Pipe With Divider PlateMade with an aluminized steel, this Universal Type A Y pipe is designed to keep the exhaust balance and gasses at...
    09-080100204
    SKU:
    09-080100204
    Length Options:
    12 Inch
    Height Options:
    12 Inch
    Material Options:
    Aluminized Steel
    Truck Class:
    Heavy Duty
    Diameter Options:
    4 Inch
    Product Type:
    Exhaust
    Make:
    Universal Items
    $317.99
    Qty in Cart: 0
    Price:
    $317.99
    Subtotal:
  • BESTfit 3.5 X 10 X 14 Inch Aluminized Steel Universal Type A Y-Pipe W/ No Divider Plate

    BESTfit 3.5 X 10 X 14 Inch Aluminized Steel Universal Type A Y-Pipe W/ No Divider Plate

    BESTFIT TRUCK PARTS

    $194.99
    Aluminized Steel Type A Universal Y-Pipe W/ 10 Inch Tail & No Divider PlateKeep the exhaust balanced and gasses at lower temperatures with this quality Y Pipe. It is constructed with a corrosion and...
    09-080100203
    SKU:
    09-080100203
    Product Type:
    Exhaust
    Material Options:
    Aluminized Steel
    Truck Class:
    Heavy Duty
    Diameter Options:
    3 Inch
    Make:
    Universal Items
    $194.99
    Qty in Cart: 0
    Price:
    $194.99
    Subtotal:
  • BESTfit 4 X 8 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider Plate

    BESTfit 4 X 8 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider Plate

    BESTFIT TRUCK PARTS

    $256.99
    BESTfit 4 X 8 X 12 Inch Aluminized Steel Universal Type A Y-Pipe With No Divider PlateAre you wanting to increase engine power? 4 State trucks offers this quality Y Pipe that can improve the flow of...
    09-080100205
    SKU:
    09-080100205
    Diameter Options:
    4 Inch
    Truck Class:
    Heavy Duty
    Material Options:
    Aluminized Steel
    Product Type:
    Exhaust
    Make:
    Universal Items
    $256.99
    Qty in Cart: 0
    Price:
    $256.99
    Subtotal:
  • Stainless Steel IFTA Permit Exhaust Bracket W/ 2 Watermelon Light Holes

    Stainless Steel IFTA Permit Exhaust Bracket W/ 2 Watermelon Light Holes

    JML KUSTOMS

    $122.99
    IFTA Permit Exhaust Bracket W/ 1 Watermelon Light Hole Per BracketImprove your truck's compliance and front-end appearance with this Stainless Steel IFTA Permit Exhaust Bracket. Made from 304...
    09-161000063
    SKU:
    09-161000063
    Product Type:
    Lighting
    Make:
    Universal Items
    Material Options:
    Stainless Steel
    $122.99
    Qty in Cart: 0
    Price:
    $122.99
    Subtotal:
  • Stainless Steel IFTA Permit Exhaust Bracket W/ 2 Watermelon Light Holes & Sticker Space

    Stainless Steel IFTA Permit Exhaust Bracket W/ 2 Watermelon Light Holes & Sticker Space

    JML KUSTOMS

    $163.99
    IFTA Permit Exhaust Bracket W/ 1 Watermelon Light Hole Per Bracket & Sticker SpaceEquip your truck with this Stainless Steel IFTA Permit Exhaust Bracket, crafted to securely display IFTA and permit...
    09-161000062
    SKU:
    09-161000062
    Product Type:
    Lighting
    Make:
    Universal Items
    Material Options:
    Stainless Steel
    $163.99
    Qty in Cart: 0
    Price:
    $163.99
    Subtotal:
  • BESTfit 304 Stainless Steel Flex Exhaust Hose - 25 Ft Roll

    BESTfit 304 Stainless Steel Flex Exhaust Hose - 25 Ft Roll

    BESTFIT TRUCK PARTS

    $599.99 - $1,209.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 6 Inch 304 Stainless Steel Flex Exhaust Hose - 25 Ft Roll25 Foot Roll of Heavy Duty Flexible...
    PPR_300053
    SKU:
    PPR_300053
    Product Type:
    Exhaust
    Diameter Options:
    6 Inch
    Material Options:
    Stainless Steel
    Make:
    Universal Items
    $599.99 - $1,209.99
    Qty in Cart: 0
    Price:
    $599.99 - $1,209.99
    Subtotal:
  • BESTfit 7 Inch OD Chrome West Coast Top Stack

    BESTfit 7 Inch OD Chrome West Coast Top Stack

    BESTFIT TRUCK PARTS

    $685.99 - $715.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 7 OD X 54 Inch Chrome West Coast Top Stack Replaces 25P-70054Cp7 OD X 54 Inch West Coast Top...
    PPR_300055
    SKU:
    PPR_300055
    Height Options:
    54 Inch
    Finish Options:
    Chrome-Plated
    Diameter Options:
    7 Inch
    Product Type:
    Exhaust
    Height Options:
    60 Inch
    Material Options:
    Steel
    Style Options:
    West Coast Turn
    Make:
    Universal Items
    Ready To Ship:
    Yes
    $685.99 - $715.99
    Qty in Cart: 0
    Price:
    $685.99 - $715.99
    Subtotal:
  • BESTfit 8 Inch OD Chrome West Coast Top Stack

    BESTfit 8 Inch OD Chrome West Coast Top Stack

    BESTFIT TRUCK PARTS

    $730.99 - $760.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 8 OD X 54 Inch Chrome West Coast Top Stack Replaces 25P-80054Cp8 OD X 54 Inch West Coast Top...
    PPR_300056
    SKU:
    PPR_300056
    Height Options:
    54 Inch
    Product Type:
    Exhaust
    Height Options:
    60 Inch
    Finish Options:
    Chrome-Plated
    Diameter Options:
    8 Inch
    Style Options:
    West Coast Turn
    Material Options:
    Steel
    Make:
    Universal Items
    Ready To Ship:
    Yes
    $730.99 - $760.99
    Qty in Cart: 0
    Price:
    $730.99 - $760.99
    Subtotal:
  • BESTfit 8 OD Inch Chrome Exhaust Stack

    BESTfit 8 OD Inch Chrome Exhaust Stack

    BESTFIT TRUCK PARTS

    $611.99 - $641.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 8 OD X 54 Inch Chrome Flat Top Exhaust Stack Replaces 24P-80054Cp8 OD X 54 Inch Flat Top...
    PPR_300045
    SKU:
    PPR_300045
    Finish Options:
    Chrome-Plated
    Material Options:
    Steel
    Diameter Options:
    8 Inch
    Height Options:
    54 Inch
    Product Type:
    Exhaust
    Style Options:
    Miter Cut
    Height Options:
    60 Inch
    Style Options:
    Flat Top
    Make:
    Universal Items
    Ready To Ship:
    Yes
    $611.99 - $641.99
    Qty in Cart: 0
    Price:
    $611.99 - $641.99
    Subtotal:
  • On Sale
    Limited Quantity Available
    BESTfit 7 OD Inch Chrome Exhaust Stack

    BESTfit 7 OD Inch Chrome Exhaust Stack

    BESTFIT TRUCK PARTS

    $405.77 - $596.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 7 OD X 54 Inch Chrome Flat Top Exhaust Stack Replaces 24P-70054Cp7 OD X 54 Inch Flat Top...
    PPR_300044
    SKU:
    PPR_300044
    Height Options:
    60 Inch
    Height Options:
    54 Inch
    Product Type:
    Exhaust
    Style Options:
    Flat Top
    Finish Options:
    Chrome-Plated
    Diameter Options:
    7 Inch
    Material Options:
    Steel
    Style Options:
    Miter Cut
    Make:
    Universal Items
    Ready To Ship:
    Yes
    $405.77 - $596.99
    Qty in Cart: 0
    Price:
    $405.77 - $596.99
    Subtotal:
  • BESTfit 5 ID Inch Chrome Curved Exhaust Stack

    BESTfit 5 ID Inch Chrome Curved Exhaust Stack

    BESTFIT TRUCK PARTS

    $394.99 - $631.99
    Choose Option(s) to see description.Fitment** Universal - Fits Multiple Makes & Models Of TrucksBESTfit 5 ID X 108 Inch Chrome Curved Exhaust StackChrome Curved Exhaust Stack* High Quality Stack*...
    PPR_300017
    SKU:
    PPR_300017
    Height Options:
    108 Inch
    Height Options:
    72 Inch
    Product Type:
    Exhaust
    Diameter Options:
    5 Inch
    Style Options:
    Curve Turn
    Finish Options:
    Chrome-Plated
    Material Options:
    Steel
    Make:
    Universal Items
    $394.99 - $631.99
    Qty in Cart: 0
    Price:
    $394.99 - $631.99
    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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