Frequently Asked Questions About International 9900/i/ix Chrome Stacks & Tops

What size exhaust stacks fit the International 9900i and 9900ix models?

The International 9900i and 9900ix typically accommodate 5-inch or 6-inch diameter exhaust stacks. Most models from 2000-2017 use a standard 5-inch pipe connection at the elbow, though some heavy-haul configurations may have 6-inch systems. Always measure your existing exhaust outlet diameter before ordering. Stack heights range from 36 to 72 inches, with 48-inch and 60-inch being the most popular for maintaining proper clearance without exceeding height restrictions.

Will these chrome stacks fit both the standard 9900i and the extended hood 9900ix?

Yes, the exhaust stacks themselves are compatible with both the 9900i and 9900ix models since the frame rails and exhaust routing are identical. However, the mounting brackets and heat shields may require different positioning on the 9900ix due to its extended hood design. Most universal mounting kits include adjustable brackets that work for both configurations. The main difference is aesthetic preference, as some drivers prefer longer stacks on the 9900ix to maintain visual proportion with the extended hood.

What grade of chrome should I choose for long-lasting shine and rust resistance?

For maximum durability, choose 304-grade stainless steel with a mirror-polished chrome finish. This grade offers superior corrosion resistance compared to 409 stainless or chrome-plated mild steel options. While 304 stainless costs more initially, it maintains its appearance 3-5 times longer in harsh weather conditions. For trucks operating primarily in dry climates or stored indoors, 409 stainless provides good value. Avoid chrome-plated mild steel unless you plan to polish frequently and store the truck indoors.

Do I need special tools or professional installation for chrome stack replacement?

Basic stack replacement requires common hand tools including socket wrenches, band clamps, and potentially a reciprocating saw for removing old stacks. Most installations take 2-4 hours per side. You'll need proper jack stands or a lift to safely access the exhaust system. Critical installation points include ensuring proper exhaust flow angle (typically 10-15 degrees outward), securing heat shields with at least 1-inch clearance from combustible materials, and using high-temperature exhaust sealant at all connections. Professional installation is recommended if you need to modify exhaust routing or install new mounting brackets.

What stack tops and accessories work best for rain protection without restricting exhaust flow?

Curved or angled stack tops provide the best rain protection while maintaining optimal exhaust flow. Look for designs with a 15-30 degree angle that direct water away from the stack opening. Straight-cut tops with rain caps offer maximum protection but can create slight back pressure. For the best balance, choose curved tops with internal baffles that prevent water intrusion while allowing unrestricted exhaust flow. Avoid weighted flapper-style caps on modern engines with exhaust brakes or DPF systems, as they can interfere with proper operation and trigger fault codes.