Ford 9" 40 spline aluminum spool 7/16" bolts (3.812" Bearing)

Mark Williams aluminum spools are up to the task to reduce rotating weight, without sacrificing strength. MW aluminum spools are machined from 7075-T6 aluminum alloy forgings and hard coat anodized for durability. Aluminum spools are approximately half the weight of the profile milled steel spools and are successfully being used in Pro Stock, Comp, Super Comp, Super Gas and Stock eliminator, Superstock cars and many more. 

The Mark Williams Advantage

• Ring gear mounting diameter is ground to precise press fit
• All mounting diameters concentric and square within .001"
• Increased cross section and generous radius under mounting prevents deforming
• Made in the USA! 

This aluminum spool by Mark Williams is designed to be used with 40 spline axles and used with a 3.812" Bearing Case (P/N 57448). Uses 7/16" bolts. Manufactured from 7075 high strength aluminum and are approximately half the weight of a lightened steel spool. 

Instructions: SB0046

Features:

• Cut for 40 spline axles
• 7075 Aluminum
• Uses 7/16" bolts
• Weighs 4.9 lbs
• Made in the USA

Note: We recommend replacing ring gear bolts every time a new gear is setup. The correct bolts for this spool are MW PN 57900