When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Direct Front Upgrade: Installs 11-3/4" vented rotors on 1937–1948 Ford cars and 1937–1947 Ford 1/2-ton pickup spindles while retaining the original 5 on 5-1/2" bolt circle, Improved Stopping Power: Features 1971–76 Impala single-piston calipers with a 2.81" bore for increased braking performance and consistent pedal feel, Wheel Compatibility: Requires disc-brake-compatible wheels with a 3-7/16" center bore; not compatible with early factory wire or drum brake wheels, Steering Arm Fitment: Works with original steering arms or flat steel steering arms; not compatible with forged aftermarket steering arms, Complete Installation Kit: Includes rotors, calipers, pads, bearings, seals, brake hoses, caliper brackets, and mounting hardware (spindle nut kit sold separately) Complete Disc Brake Kit 1937-48 Ford, 5 on 5-1/2 BC Sku # 91031909 Mfr. Part # 91031909 Condition New Brand Speedway Motors Sold Kit Details
This completedisc brake kit easily installs big 11-3/4" rotors on your 1937-1948 Ford car or 1937-1947 Ford 1/2 ton pickup spindleswhile retaining the original 5 on 5-1/2" bolt circle.
This kit will work with spindles having either original steering arms or with flat steel steering arms. It willNOT work with forged aftermarket steering arms. Wheels must have 3-7/16" center hole and have been designed for disc brake applications. WillNOT work with early Fordfactory wire or steel drum brake wheels. You will need to use a later disc brake steel wheel or aftermarket wheel.
Item Details'Ford 11-3/4" rotors to ''37-''47 Ford 1/2 ton pickup & ''37-''48 Ford car spindles' Specs Sold in Quantity Kit Notes Includes rotors, bearings and seals, calipers, pads, brake hoses, brake tabs, and caliper brackets. MFG. Part # 91031909 Position Front Wheel Bolt Pattern (in.) 5x5.5 in. Wheel Bolt Pattern (mm) 5x135 mm Rotor Diameter 11.75 Inch Rotor Type Vented Caliper Pistons One Caliper Finish Natural Parking Brake Provision No Minimum Recommended Wheel Diameter 15 Inch Rotor Shape Round Hardware Included Yes Rotor Style Plain Face Spindle Type Not Applicable Front Suspension Type Straight Axle Front Rotor Included Yes Front Rotor Diameter 11.75 Inch Front Caliper Included Yes Rear Caliper Included No Front Spindles Included No Master Cylinder Included No Brake Booster Included No Brake Hoses Included Yes Ford Bearing End Style Not Applicable Rear Rotor Included No Bolt Pattern 5 on 5.5" Color Natural Front Caliper Finish Natural Front Caliper Piston Quantity 1 Application Type 37-48 Ford Car Spindle Reviews Yes Rated by Steve on May 03, 2026
Summary: Everything fit well and I could have finished the job in six hours if I didn't have to search for an adapter to make the stock brake line work. I would think the adapter would be included or the hose supplied would have a fitting that match the stock brake lines.
Yes, I recommend this product.
Review Rated by Harry on April 26, 2026
Summary: Disc Brakes for 1940 Ford Pick-Up
Yes, I recommend this product.
glad i looked for the disc brake kit Rated by misfit on March 26, 2026
Summary: I am very pleased with the instilation process. I can use my stock 40 Ford wheels.
Yes, I recommend this product.
Yes Rated by 40 chevy on February 15, 2026
Summary: Everything went really good and the fit was perfect
Yes, I recommend this product.
I would recommend this product Rated by Smitty on December 30, 2025
Summary: No complaints
Yes, I recommend this product.
Related Items / Suggested Parts Speedway Vintage 15x6 Plain Steel Wheel, 5 on 5.5, 3.5 Inch BS Lucas Oil 105741 Red N Tacky Grease #2, 16oz Cartridge Basic Disc Brake Kit, 1937-48 Ford Spindle to F-150 Rotors, 5 on 5-1/2 1937-1948 Ford Spindle Castle Nuts Redline 80402 CV-2 Synthetic Grease Speedway Vintage 15x6 Steel Wheels, 5 on 5.5, 3.5 Inch BS Speedway Ford Flat Plate Steering Arms, Plain Speedway 1928-1948 Ford Forged Spindles w/ King Pins Speedway Purple Adjustable Brake Proportioning Valve Speedway Drum Brake Residual Valve, 10 PSI, Purple Speedway Disc Brake Residual Valve, 2 PSI, Purple Speedway Standard 1942-48 Ford Spindle King Pin Set Tech Support We're here to help before and after your purchase. If you have a question or need assistance with one of our products, please contact us through Messaging and a knowledgeable Speedway Motors team member will be happy to help. About Speedway Motors is America’s Oldest Speed Shop® and has been a trusted source for specialty rodding and racing products and friendly expert advice for more than 74 years. Founded in 1952 by “Speedy” Bill Smith – a racer and street rodder himself – Speedway has grown from a one-man operation to become the world’s largest manufacturer, distributor and retailer of street rod and racing products. Our industry-leading fast delivery is the result of same-day shipping from our state-of-the-art, centrally located 500,000 sq. ft. headquarters. Speedway’s size offers customers unmatched product selection and low pricing, while our excellent technical support and customer service have made us a recognized leader in the rodding and racing industries.
