AP Astro Pneumatic Tool Company exhaust pipe stretcher kit, Metallic — impact‑driven, 1-5/8"–4-1/4" range

The Astro Pneumatic 78835 Exhaust Pipe Stretcher Kit is a heavy-duty, impact-driven expander set that stretches and sizes exhaust pipes from 1-5/8" to 4-1/4" for reliable fit-up and sealing.

Built for professional mechanics and serious DIYers, this metallic exhaust pipe stretcher kit delivers repeatable expansion with a hardened steel expander and seven collet sizes. The tool is impact-driven and uses a 28mm bolt head to transfer force, enabling quick on-vehicle adjustments and tight seal creation where exhaust joints need precise sizing. Designed by AP Astro Pneumatic Tool Company, the kit focuses on durability and ease of use to speed up exhaust assembly and repair tasks.

How does this kit make exhaust pipe fitting faster?

The kit lets you expand the pipe end quickly using an impact driver rather than slow manual methods, cutting prep time on pipe joints. Its range of collet sizes eliminates frequent tool swaps and gets parts ready for clamp or weld attachment in a single operation.

• Impact-driven design for rapid expansion with an 28mm bolt head
• Seven collets covering 1-5/8" to 4-1/4" diameters for versatile sizing
• Collets are 2" long to provide stable, even expansion along the pipe lip

What materials and torque recommendations should I follow?

The expander and collets are steel for strength under impact loads and repeated use. Apply the included grease to threads before use to reduce wear; use an impact wrench rated at 800 ft-lbs or higher for most applications to ensure the collet fully expands without damaging the tool.

• Hardened steel expander and steel collets for long service life
• Grease threads before assembly to protect components
• Recommended impact wrench rating: 800 ft-lbs and above for full performance

Which pipe sizes and fit scenarios does the 78835 cover?

The kit covers a broad span of common automotive exhaust diameters, making it useful for OEM replacements, custom exhaust work, and repair of rusted or crushed ends. Each collet increments sizing so you can select the closest fit for even expansion and better sealing when clamping or welding.

• Collet size coverage: 1-5/8" through 4-1/4" diameters
• Seven collets included for incremental, precise control
• Suitable for passenger vehicles, light trucks, and many custom exhaust pipes

How do I use and maintain the exhaust pipe stretcher safely?

Set the correct collet for the pipe diameter, apply grease to the tool threads, and drive the 28mm bolt head with the recommended impact wrench until the pipe reaches the desired expansion. After use, clean the collets and store them dry; inspect threads and mating surfaces regularly for wear and re-grease before the next job.

• Select collet matching pipe inner diameter, then seat collet in expander
• Use 28mm impact socket and impact wrench rated ≥800 ft-lbs; apply grease
• Post-use: clean, check for wear, and store in a dry container

Who is this for: The Astro Pneumatic 78835 is aimed at professional shops, exhaust specialists, and advanced DIYers who need a dependable, heavy-duty expander set to streamline exhaust assembly and repair. If you regularly work on exhaust systems—whether replacing factory sections, building custom systems, or restoring damaged pipes—this kit supplies the collet range, durability, and impact compatibility to save time and produce consistent joints.