Skip to content
Boschma's Speed Shop
0 items in cart

Select your vehicle

Pick your year, make, model, and engine to see parts for your build.

Browse all parts

Only parts with confirmed fitment for your vehicle are shown. Don't see your vehicle? Ask us about fitment.

Cart

Your cart is empty.

Expanded product image

Steeda S550 Mustang Threaded Differential Through Bolt Upgrade Kit (2015-2022)

Steeda

Steeda S550 Mustang Threaded Differential Through Bolt Upgrade Kit (2015-2022)

Part #: 555-4051

Product details

Verified vehicle fitment

  • 2015–2022 Ford Mustang — V6, GT, EcoBoost, Bullitt, Mach 1Steeda lists these model years and trims: V6, GT, EcoBoost, Bullitt, Mach 1. Engine coverage is not explicitly specified here. This is not confirmation of every trim or setup: check the individual product description for exclusions, transmission, brake, suspension and other installation requirements before ordering.

Not sure it fits your build?

Ask the shop

Description

Upgrade your S550 Mustang IRS differential hardware with Steeda's all new through Threaded Differential Bolt Upgrade Kit. Through bolting the rear super 8.8" differential to the IRS subframe on S550 Mustangs has become a popular modification due to premature bolt failure. Rather than permanently modifying your subframe by drilling out the bushings and differential housing, Steeda designed and machines in house a custom high strength hardened bolt that completely threads through the system. Post heat treatments the machined parts are nickel plated to prevent galling and provide superior corrosion protection. Using heat treated 4130 Chromoly steel, these custom bolts are as strong as a class 12.9 fastener and have been proven to last on some of the quickest and fastest S550 Mustangs out there, including Steeda's Silver Bullet.Steeda's S550 Mustang THRU Threaded Differential Bolt Upgrade Kit is a must for all performance enthusiast looking for some bolt-in peace of mind.Intended to be used in conjunction with our all new 555-4050 - Steeda HARDCORE S550 Mustang Differential Brackets.Product Benefits No permanent modification Custom designed for this applicationNickel plated to prevent galling Upgraded hardware over OE Heat treated 4130 Chromoly for similar strength to grade 12.9 hardware

Part details

Manufacturer
Steeda
Part number
555-4051
Category
Suspension
Compatibility
Verified for 1 vehicle (listed above)
Shipping & returns

Shipping is calculated at checkout from the part and your address. Some parts ship direct from the manufacturer, so they may arrive separately.

Shipping policyRefund policy

Related parts

Shop all
  • Steeda Mustang Adjustable Rear Swaybar Endlinks (2015-2026)

    Steeda

    Steeda Mustang Adjustable Rear Swaybar Endlinks (2015-2026)

    Price: $189.95
  • Steeda Mustang Billet Rear Spring Spacer 1/8" All (2015-2026)

    Steeda

    Steeda Mustang Billet Rear Spring Spacer 1/8" All (2015-2026)

    Price: $49.95
  • Steeda Mustang Pro-Action Front Coilovers - No Camber Plates or Springs (2015-2026)

    Steeda

    Steeda Mustang Pro-Action Front Coilovers - No Camber Plates or Springs (2015-2026)

    Price: $1,049.95
  • Steeda Mustang Convertible Low-Profile Jacking Rails (2015-2026)

    Steeda

    Steeda Mustang Convertible Low-Profile Jacking Rails (2015-2026)

    Price: $249.95

Price match guarantee

Found it cheaper? We will match it.

See any part we sell for less at another authorized US retailer? Call or email us with the link and we will match the price.

Cartoon mechanic riding a supercharged Mustang and cutting a price tag in half

November Full Send Sale

10% off every order. All month.

Our mechanic got carried away with the scissors. Hit the button and code FULLSEND10 is applied at checkout for you.

Code: FULLSEND10

18Days
21Hrs
30Min

Ends November 30 at 11:59 PM Eastern.

Plus, we price match any part.

Full send my 10% off