Billet Output Shaft

Features:

• Fits 2011–2018 6.6L Duramax with Allison 1000
• Made from high-strength 300M billet steel
• Ideal for towing, racing, or off-road use
• Designed for extreme torque and stress loads
• Precision ground for maximum dimensional accuracy
• Stronger than stock cast or forged shafts
• Reduces risk of twisting or shaft failure
• Engineered for heavy-duty service applications
• Backed by real-world failure analysis data
• Proprietary SunCoast manufacturing and heat treatment
• Perfect upgrade for high horsepower builds

Built To Handle What Your Duramax Dishes Out

If you're serious about power and putting it to the ground without compromise, the SunCoast A1-109102 Billet Output Shaft is a critical upgrade you shouldn't overlook. Whether you're towing heavy loads, launching hard at the track, or pushing big torque through your Allison 1000, a stock output shaft simply isn’t built to keep up. This billet shaft is forged from premium 300M steel and built for one purpose, survive the abuse that breaks factory parts. Precision machining ensures a flawless fit and tight tolerances, while its proprietary heat treatment process gives it the strength to handle the kind of stress high-performance builds demand. You won't find weak points here, just purpose-built strength backed by real-world failure analysis. SunCoast has spent years studying what breaks and why, then engineering parts to fix it for good. If you're looking for the kind of part you install once and never think about again, this is it.

Precision Machined For Maximum Strength And Longevity

The SunCoast A1-109102 Billet Output Shaft is designed for 2011–2018 GM 2500HD and 3500HD trucks running the Allison 1000 transmission. Made from aerospace-grade 300M billet steel, this shaft offers significantly more strength and fatigue resistance than factory cast or forged units. Each shaft is precision ground to exacting dimensional tolerances, which reduces runout and ensures perfect alignment with transmission components. This not only improves power transfer efficiency but also minimizes internal stress that can lead to premature wear or failure. Ideal for high horsepower applications, heavy hauling, or aggressive driving, the A1-109102 is engineered to withstand the high shock loads that come from big torque and sudden drivetrain stress. SunCoast’s proprietary heat treatment process further enhances its durability, making it a trusted choice for diesel enthusiasts who refuse to compromise. With years of OEM failure analysis behind its design, this output shaft is built not just to last, but to lead.

Fitment: 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Notes:

• Fits 2011–2018 GM Silverado/Sierra 2500HD and 3500HD
• Designed for use with Allison 1000 transmissions
• Made from high-strength 300M billet steel
• Ideal for high torque, heavy-duty applications
• Recommended for racing, towing, or off-road builds
• Precision ground for tight tolerances and fitment
• Engineered to reduce risk of shaft twisting or failure
• Developed through extensive OEM failure analysis
• Proprietary heat treatment process for added durability
• Built in-house by SunCoast to exacting standards