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UP49504 - LongTube Headers for Workhorse W-Series 8.1L (2001-2003)

New UP49504  -  LongTube Headers for Workhorse W-Series 8.1L (2001-2003)


Order Shipment Notice: 

Most orders are shipped within 24 hours from the order date. Orders placed on the weekend or after cutoff on Friday, and orders placed on select holidays are processed on the next business day. Please see our shipping terms for more information.


One look at these LongTube Headers tells you how radically different they are from the stock exhaust manifolds. Constructed of heavy-wall, T304 series stainless steel, these headers have 5/8 inch-thick flanges that are welded on both sides for optimum reliability. They never crack, leak or fail. We do recommend using OEM exhaust manifold gaskets when installing.

Tuned-length tubes produce a huge reserve of low-end torque that proves its worth on every steep grade and short onramp. Now your Workhorse climbs faster and stronger, without the transmission struggling between gears. The muscle to stay in higher gears longer not only stops annoying "shift happy" performance, it lessens the load on your engine and transmission. Here's power to reach freeway speed sooner for safe merging and passing.


  • 2001-2003 W-Series 8.1L Chassis - Allison Transmission - EGR Equipped
  • Can be modified to work on 2004+ W-Series 8.1L by blocking off the EGR tube on the right side header.

Kit Contents:

  • Right Side Header
  • Left Side Header
  • Right Side Connector Pipe
  • Left Side Connector Pipe
  • x2 2 Bolt Flange Gaskets
  • x2 3 Bolt Flange Gaskets
  • EGR Flange Gasket
  • x6 3/8"-16 x 1-1/4" Hex Bolts
  • x6 3/8"-16 Hex Nuts
  • x6 3/8" Split Lock Washers
  • x6 3/8" Flat Washers
  • x2 M8-1.25x30mm Double Ended Studs
  • x2 M8-1.25 Hex Nuts

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 The state of California requires that this warning be posted for people purchasing products that reside in California.

WARNING: Products may contain one or more chemicals known in the State of California to cause cancer and/or birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov

VIN Verification Service Item

This product allows for a VIN verification service.

  • VIN part verificaion is a service that we provide free of charge when a part is purchased.
  • When you provide your VIN below we will personally verify your part selection by your VIN before shipment of your order.
  • This helps ensure that this is the correct part for your vehicle.
  • This is not an automatic VIN check, it is done by a parts specialist once order is placed.
  • We can only VIN verify vehicles back to model year 1996, if older we can help but can't guarantee fitment.
  • If you would like to have your part selection verified before purchase please call or email us.
  • Views: 1464
  • Product Code: UP49504
  • Availability: In Stock
  • $1,595.00