BTK S58 Dual Differential Mount - G80 M3 | G82 M4 | G87 M2

/ PRODUCT ·BUILTTOKILLUSA

BTK S58 Dual Differential Mount

Name: BTK S58 Dual Differential Mount - G80 M3 | G82 M4 | G87 M2
Brand: BuiltToKillUSA
SKU: sku-45202671271980
Price: 549.99 USD
Availability: InStock

[ VERIFIED FITMENT ]

G80 M3G82 M4G87 M2

Bushing Option

No Bushing

80A Bushing (needed for installation)

Pick Style

Type 3 Hard Anodized

Raw Billet

$549.99

Shipping calculated at checkout.

IN STOCK

Shipped from USA

Additions

BTK S58 Dual Differential Mount

G80 M3G82 M4G87 M2

from $524.99

/ 01 · OVERVIEW

MADE IN SAN CLEMENTE, CA 🇺🇸

All assembly hardware included
Installation guide available on @BuiltToKillUSA Instagram or the RVNGRaceworks YouTube channel.

The BuiltToKillUSA Differential Dual Mount is designed to reinforce one of the G8X platform’s known weak points by utilizing the unused factory secondary bushing location. By adding a second support point, the mount helps stabilize the differential during hard acceleration, aggressive launches, and spirited driving while improving overall driveline response.

Installation is straightforward with no disassembly of OEM differential components required. Simply install the bushing, mount the assembly to the differential, and gain significantly improved driveline support.

WHAT IS A DUAL DIFF MOUNT?

The Dual Diff Mount ties both sides of the differential into the subframe instead of relying on a single mounting point. This helps distribute torque load more evenly under acceleration, launches, and aggressive shifting, especially on higher horsepower and high torque setups where differential movement becomes more pronounced.

Benefits include:
• Reduced differential movement and wind-up
• More consistent driveline geometry
• Reduced wheel hop
• Improved traction consistency
• Less shock loading on axles and bushings

CONSTRUCTION & DESIGN

• Precision machined in the USA from 6061 aluminum
• Lightweight 20 oz complete assembly
• Designed for maximum rigidity without unnecessary weight

TYPE III HARD ANODIZED FINISH

Each mount features a Type III hard anodized coating for maximum durability and long term performance.

Benefits include:
• Extreme hardness and wear resistance
• Thick protective oxide layer for improved scratch and corrosion resistance
• Enhanced durability under high stress conditions
• Improved chemical resistance and lubricant retention

This finish is compliant with MIL-A-8625 Type III standards, a military grade specification used for aluminum components subjected to demanding use.

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Ships in 1-3 Days

Flat Rate Shipping

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Processing: In-stock items typically ship within 1–3 business days. We do our best to get every order out as quickly as possible. All orders are quality-checked and ship with full insurance coverage. If an item is out of stock, we'll reach out ASAP with an ETA.

Carriers: Carbon fiber and performance parts ship via UPS. Smaller items ship via USPS.

Tracking: You'll receive a confirmation email when your order ships with a tracking link — you can also track it anytime from the order page linked in that email. Allow 1–3 business days for tracking to update.

International: We ship worldwide. Contact us at sales@horizonmotorsport.com for international shipping quotes.

Signature: We may require a signature for high-value orders. Please be available during your estimated delivery window.

FEATURED BUILD

G80 M3 Competition

OWNER

AP2 Performance

Orange County, CA

SPEC SHEET

VR1 FRONT GRILLSP2 FRONT LIPPERFORMANCE V1 SIDE SKIRTSPERFORMANCE V1 DIFFUSERPERFORMANCE V1 INLETS

F80 M3

OWNER

Brian

Los Angeles, CA

SPEC SHEET

CS V2 FRONT LIPPERFORMANCE V1 SIDE SKIRTSV STYLE DIFFUSERPERFORMANCE V2 MIRROR CAPSGTS STYLE HOOD

@bbriaann_

A90 Supra

OWNER

Danny

Orange County, CA

SPEC SHEET

AG1 FRONT LIPAG1 SIDE SKIRTSAG1 REAR SPATS

OWNER

Brandon

Irvine, CA

SPEC SHEET

VR1 FRONT LIPCSL V1 FRONT GRILLPERFORMANCE V1 INLETSPERFORMANCE V1 MIRROR CAPSHM S58 CATBACK EXHAUST

Horizon Motorsport - Est. 2019

Built for BMW Enthusiasts

We specialize in quality aftermarket parts for BMW M-cars. Every part we carry is selected, inspected, and shipped with the same care you'd give your own build. Our goal: help you get your car looking and performing exactly how you envisioned it.

Learn More

/ ? · ASK A QUESTION

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Fitment uncertainty, install details, compatibility with other mods — whatever it is, our team replies personally, usually within 24 hours.

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BTK S58 Dual Differential Mount

Additions

Built by Our Customers

AP2 Performance

Brian

Danny

Brandon

Built for BMW Enthusiasts

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