Deep Tub Kit w/Frame Rail Section - Mustang

The Detroit Speed Engineering Deep Tub Kit w/Frame Rail Section for 1964.5–1970 Ford Mustang delivers the chassis clearance serious restomod builders and performance enthusiasts need when running modern suspension geometry or larger tire packages. This is purpose-built metalwork that solves a fundamental problem: factory wheel wells on classic Mustangs were never engineered for wide modern wheels, performance brakes, or independent rear setups. The deep tub design expands usable interior wheel cavity volume, allowing you to fit tires and components that would otherwise bind or foul against the original structure.

Manufactured from 18-gauge steel in natural (unpainted) finish, this kit includes both the deep tub section and a frame rail component, giving you a complete structural solution that maintains OEM attachment points and suspension mounting integrity. The 3-inch width specification refers to the extended tub depth—a measured increase that clears wheel and tire profiles without requiring full floor pan replacement. At 32.9 lbs and dimensioned at 23.5 x 12.5 x 36 inches, the kit is manageable for installation while providing substantial material coverage. The gauge and steel composition ensure proper rigidity and weldability, critical when integrating this piece into your vehicle's unibody structure.

Builder-level Mustang owners—those upgrading to modern-width wheels, independent suspension systems, or oversized brake packages—benefit most from this engineering solution. Installation requires welding and chassis fabrication skills; this is not a bolt-on accessory. The frame rail section inclusion means you're addressing both tub and structural support simultaneously, reducing secondary modifications downstream. Verify fitment against your specific Mustang year (1964.5–1970 range) and confirm wheel/suspension specifications before purchase to ensure this kit aligns with your build goals.