Genuine Mazda Rear Subframe Brace Bar Mounting Bolt • 99466-1225

Genuine Mazda Rear Subframe Brace Bar Mounting Bolt

Replacement Genuine Mazda rear subframe brace-bar mounting bolt for Mazda MX-5 Mk3, Mk3.5 and Mk3.75 NC models fitted with 1.8- or 2.0-litre petrol engines.

This flange bolt secures the rear underbody brace bars or cross braces in the rear subframe area. The braces connect the rear subframe region to the vehicle body and contribute to the rigidity and structural support of the rear chassis assembly.

Correct fasteners are important because the brace bars are exposed to road spray, corrosion, chassis movement and repeated suspension loads. Missing, seized or weakened bolts can prevent the braces from being secured correctly.

Six bolts are used across the complete rear brace-bar arrangement on each MX-5 NC. This listing supplies one Genuine Mazda bolt, so order a quantity of six when renewing the complete fastener set.

Important contents information: This listing is for one mounting bolt only. The rear brace bars, retaining nuts and other rear subframe components are not included.

• Part type: Rear subframe brace-bar mounting bolt
• Common names: Rear cross-brace bolt / underbody brace bolt / subframe support-bar fastener
• Mazda catalogue description: Bolt
• Location: Rear underside of vehicle, around the rear subframe and body mounting points
• Function: Secures the rear underbody brace bars / cross braces
• Quantity fitted per MX-5 NC: 6
• Quantity supplied: 1 bolt
• Brace bars included: No
• Retaining nut included: No
• Rear subframe included: No
• Brand: Genuine Mazda
• Part No.: 99466-1225
• MX-5 fitment: All Mk3, Mk3.5 and Mk3.75 NC 1.8 and 2.0 models

Typical reasons for replacement:

• Bolt heavily corroded from road exposure
• Bolt seized during brace-bar removal
• Threads damaged or cross-threaded
• Bolt head rounded during removal
• Bolt bent, stretched or fractured
• Original fastener missing
• Rear brace-bar replacement or retrofit
• Rear subframe removal or refurbishment
• Previously fitted incorrect or non-standard hardware

Quantity advice: Six bolts are used across the complete MX-5 NC rear brace-bar arrangement. This listing supplies one bolt per order quantity.

Fitment advice: 99466-1225 fits the rear underbody brace-bar installation used across the complete MX-5 NC range. Confirm how many mounting positions are being dismantled before ordering.

Replacement advice: Inspect all mounting bolts, retaining nuts, brace-bar apertures and body mounting points. A replacement bolt will not correct stripped captive threads, elongated mounting holes, damaged brace bars or severe corrosion in the surrounding structure.

Corrosion advice: These fasteners are positioned beneath the vehicle and are commonly exposed to water, road salt and debris. Apply penetrating fluid before dismantling heavily corroded hardware and avoid using excessive force that could damage a captive mounting point.

Other items to consider: Inspect both rear brace bars, all six mounting positions, the rear subframe, nearby suspension-arm mountings and surrounding underbody corrosion protection.

Useful tools / consumables: Socket and spanner set, calibrated torque wrench, penetrating fluid, wire brush, thread-cleaning tools, suitable vehicle lifting equipment and corrosion-protection treatment where appropriate.

Difficulty guide: DIY Difficulty: Easy to Moderate. The bolt positions are accessible from beneath the vehicle, although corrosion and damaged captive threads can make the repair more involved.

Why Genuine Mazda? Genuine Mazda brace-bar fasteners match the original thread specification, bolt length, flange profile and strength requirements. Correct hardware helps provide the intended clamping force without interfering with the brace-bar or underbody mounting geometry.

What’s in the box: One Genuine Mazda rear subframe brace-bar mounting bolt, part number 99466-1225.

Installation notes: Raise and support the vehicle safely before working underneath it. Support the brace bar before removing its mounting hardware. Clean and inspect the threaded mounting point, brace-bar aperture and surrounding body structure. Start the replacement bolt by hand to prevent cross-threading, position the brace correctly and install all fasteners loosely before tightening them progressively using the applicable Mazda procedure. Confirm that the brace sits flat against every mounting point without distortion.