Peterbilt 357/378 Exhaust Kits

Frequently Asked Questions About Peterbilt 357/378 Exhaust Kits

Will these exhaust kits fit my specific year Peterbilt 357 or 378?

Our exhaust kits are designed to fit Peterbilt 357 models from 1987-2001 and Peterbilt 378 models from 1986-2007. However, some variations exist based on your truck's original exhaust configuration (single vs. dual), wheelbase, and whether you have a day cab or sleeper. We recommend checking your current exhaust pipe diameter and measuring from the turbo outlet to where you want the stacks to exit. Most kits accommodate standard 5-inch diameter systems, but some older models may have 4-inch systems that require adapters.

What's included in a complete exhaust kit, and what additional parts might I need?

A complete exhaust kit typically includes straight pipes or muffler pipes, elbows, stack brackets, clamps, and bushings. However, you may need to purchase separately: exhaust manifold gaskets, turbo outlet gaskets, flex pipe (if your setup requires it), and chrome heat shields. If converting from single to dual exhaust, you'll also need a Y-pipe splitter. Most installations require 5-inch band clamps, which are sometimes sold separately depending on the kit.

Are these kits made from aluminized steel or stainless steel, and which is better for my application?

We offer both stainlees steel and chromed steel options. Chromed steel kits cost less and provide good corrosion resistance for 5-7 years under normal conditions. Stainless steel kits (usually 409 or 304 grade) last significantly longer, resist rust better in harsh climates, and maintain their appearance with less maintenance. If you operate in areas with heavy road salt or coastal regions, stainless steel is worth the extra investment.

How difficult is installation, and can I do it myself?

Installation difficulty varies by kit type. Straight pipe replacements are typically a 2-4 hour job for someone with basic mechanical skills and proper tools. You'll need pipe hangers, a sawzall or pipe cutter for any custom fitting, and possibly a floor jack to support the pipes during installation. Turbo-back complete systems are more complex and may require 4-6 hours. Common challenges include aligning multiple sections properly and ensuring adequate clearance from cab, frame, and air lines. Having a helper makes the job much easier, especially when positioning longer stack sections.

What stack styles and lengths work best for Peterbilt 357/378 trucks?

The most popular configurations are 6-inch or 7-inch diameter stacks in either straight cut, curved tip, or miter cut styles. For height, 36-inch to 48-inch stacks are standard for day cabs, while sleeper cabs often run 60-inch to 72-inch stacks to clear the roof line. West Coast style curved stacks are popular for their classic look, while straight stacks with chrome tips provide a cleaner appearance. Consider your state's regulations, as some limit stack height to no more than 13.5 feet from ground level. Bull hauler stacks (8-inch diameter) are available but may require additional bracket modifications.