BMW E46 3 Series Front Strut Tower Reinforcement Plates – Upper Shock Mount Support for 320i 323i 325i 328i 330i 325xi 330xi | Replaces Part No. 51717036781

Strengthen the front suspension mounting points of your BMW E46 with these front strut tower reinforcement plates, designed to help distribute suspension loads across a larger area of the vehicle's front strut towers. Suitable for select BMW E46 3 Series models, these reinforcement plates provide additional support at one of the chassis areas subjected to repeated suspension loading.

The BMW E46 is known for its responsive handling and well-balanced suspension design. However, repeated impacts from potholes, uneven roads, and aggressive driving can place substantial loads on the upper front strut mounting areas. Vehicles equipped with lowered suspension, stiffer springs, or performance coilovers may experience increased loading at these mounting points.

Over time, concentrated suspension forces can contribute to deformation of the sheet metal surrounding the front strut mounts. This condition is commonly referred to as strut tower mushrooming, where the upper mounting surface begins to deform or rise around the strut mounting studs.

These reinforcement plates are designed to fit between the front upper strut mount and the underside of the strut tower. By adding a reinforcing layer at the mounting interface, the plates help distribute suspension forces and reduce localized stress on the surrounding sheet metal.

Unlike exterior strut tower braces, which connect the upper suspension towers across the engine bay, these reinforcement plates work directly at the strut mounting interface. They can be used independently or alongside a compatible front strut brace to provide additional support to the suspension mounting structure.

Whether maintaining an original E46, installing aftermarket suspension components, or preparing a vehicle for spirited street driving, front strut tower reinforcement plates are a practical preventive upgrade for the BMW E46 chassis.

Key Features

• BMW E46-Specific Design: Intended for the front upper strut mounting configuration used on compatible BMW E46 3 Series models.

• Helps Prevent Strut Tower Mushrooming: Adds reinforcement at the upper front strut mounting interface to reduce the risk of localized sheet-metal deformation.

• Improved Load Distribution: Helps spread suspension mounting loads across a larger area of the strut tower.

• Factory-Style Reinforcement Concept: Based on the reinforcement plate configuration associated with BMW's original E46 suspension applications.

• Compatible with Stock Suspension: Suitable for correctly matched factory strut mounting arrangements.

• Useful for Lowered Suspension: Particularly beneficial on vehicles equipped with lowering springs, sport shocks, or coilovers.

• Front Left and Right Application: The corresponding plate design is used on either front strut tower.

• Concealed Installation: Installs underneath the strut tower rather than as an exposed engine bay accessory.

• No Welding Normally Required: Designed to be secured within the existing strut mounting arrangement.

• Preventive Suspension Upgrade: Helps protect an important chassis mounting area from concentrated suspension loading.

Benefits of Front Strut Tower Reinforcement

Helps Reduce Strut Tower Deformation

The E46 front strut towers are constructed from formed sheet metal. Repeated suspension impacts can place concentrated forces around the upper strut mounting points.

Adding a reinforcement plate helps distribute these forces across a broader mounting area.

Recommended for Performance Suspension

Lowering springs, stiffer dampers, and certain coilover configurations can transmit greater loads into the body structure.

Reinforcement plates provide additional support at the upper strut mounting interface, making them a useful addition when upgrading suspension components.

Supports Long-Term Chassis Preservation

Preventing deformation is generally preferable to repairing a damaged strut tower.

These plates are intended to reduce the likelihood of mounting-area distortion when installed on an undamaged and compatible chassis.

Compatible with Front Strut Braces

A front strut brace and front reinforcement plates serve different purposes.

A strut brace connects the suspension towers across the engine bay, while reinforcement plates support the individual upper strut mounting interfaces.

Both may be installed together when the suspension configuration allows.

Factory-Style Installation

The reinforcement plates fit within the original suspension mounting arrangement and do not normally require cutting or welding on compatible standard E46 applications.

FITMENT

BMW E46 3 Series Sedan

• BMW 320i – Select 1998–2005 applications

• BMW 323i – 1999–2000

• BMW 325i – 2001–2005

• BMW 325xi – 2001–2005

• BMW 328i – 1999–2000

• BMW 330i – 2001–2005

• BMW 330xi – 2001–2005

BMW E46 3 Series Coupe

• BMW 320Ci – Select applications

• BMW 323Ci – 2000

• BMW 325Ci – 2001–2006

• BMW 328Ci – 2000

• BMW 330Ci – 2001–2006

BMW E46 3 Series Convertible

• BMW 320Ci Convertible – Select applications

• BMW 323Ci Convertible – 2000

• BMW 325Ci Convertible – 2001–2006

• BMW 330Ci Convertible – 2001–2006

BMW E46 Touring / Wagon

• BMW 320i Touring – Select applications

• BMW 325i Touring – Select applications

• BMW 325xi Touring – Select applications

• BMW 330i Touring – Select applications

• BMW 330xi Touring – Select applications

Model-Year Clarification

The supplied product title lists 2002–2006, but BMW E46 reinforcement plate applications extend to earlier model years.

• E46 Sedan: Generally 1999–2005 in North American applications

• E46 Coupe: Generally 2000–2006

• E46 Convertible: Generally 2000–2006
  

Production dates and international-market configurations may differ.

Engine Compatibility

Front strut tower reinforcement plate compatibility is determined primarily by the E46 chassis, upper strut mount, and front suspension configuration, rather than engine displacement.

M52TU Inline-Six

• BMW 323i / 323Ci – 2.5L

• BMW 328i / 328Ci – 2.8L

M54 Inline-Six

• BMW 320i / 320Ci – Select 2.2L applications

• BMW 325i / 325Ci / 325xi – 2.5L

• BMW 330i / 330Ci / 330xi – 3.0L

S54 Inline-Six

• BMW E46 M3 – 3.2L

M3 applications require additional installation clearance verification.

Additional Engines

Selected E46 four-cylinder and diesel models may use a compatible upper strut mounting arrangement. Verify the suspension configuration before ordering.

OEM Replacement Part Numbers

Primary BMW Reference

• 51717036781

• 51 71 7 036 781

• 51-71-7-036-781

Earlier Reference

• 41114287198

• 41 11 4 287 198

The earlier reference is documented in BMW parts supplier cross-reference catalogs.

These numbers identify the corresponding original reinforcement plate application. They do not establish that the aftermarket product is manufactured by BMW.

Product Specifications

• Product Type: Front Strut Tower Reinforcement Plate

• Vehicle Manufacturer: BMW

• Vehicle Platform: E46 3 Series

• Primary OEM Reference: 51717036781

• Earlier Reference: 41114287198

• Installation Location: Front Upper Strut Mount / Underside of Front Strut Tower

• Compatible Positions: Front Left and Front Right

• Primary Function: Upper Strut Mounting Area Reinforcement

• Construction: Metal Reinforcement Plate

• Exact Material Grade: Supplier Verification Required

• Surface Coating: Verify Actual Product Finish

• Plate Thickness: Not Independently Verified

• Mounting Design: Factory-Style Upper Strut Mount Interface

• Compatible Suspension Types: Selected Factory Struts, Sport Suspension, and Aftermarket Coilover Configurations

• Welding Required: Normally No

• Installation Method: Mechanical Installation During Upper Strut Mount Access

• Electronic Programming: Not Required

• Intended Use: Front Suspension Mounting Reinforcement

• Product Category: Aftermarket Suspension and Chassis Reinforcement

Package Contents: Confirm whether the actual BAVMODS® SKU includes two reinforcement plates or one individual plate.

One plate is used per front strut tower. A complete two-sided installation requires two plates.

Mounting nuts, rivets, strut mounts, and suspension components are not automatically included.

Installation Instructions

Professional installation is recommended because the procedure involves the front suspension assembly and load-bearing suspension fasteners.

1. Park the vehicle on a level surface.

2. Engage the parking brake and secure the vehicle against movement.

3. Confirm the reinforcement plates match the original E46 upper strut mounting arrangement.

4. Inspect both front strut towers for visible deformation, cracks, corrosion, or previous repairs.

5. Do not install reinforcement plates as a substitute for structural repair if significant damage is present.

6. Follow the BMW service procedure for accessing and removing the front strut assembly.

7. Safely raise and support the vehicle where required.

8. Remove the relevant wheel for suspension access.

9. Support the suspension assembly appropriately.

10. Disconnect or reposition components as specified by the BMW service procedure.

11. Remove the front strut assembly using the correct suspension service procedure.

12. Avoid allowing the suspension or steering knuckle to hang unsupported.

13. Inspect the upper strut mount and mounting studs.

14. Inspect the underside of the front strut tower.

15. Clean dirt and debris from the mounting surface.

16. Compare the reinforcement plate with the strut mount mounting pattern.

17. Check that the plate fits the intended mounting surface without interference.

18. Position the reinforcement plate between the upper strut mount and the underside of the strut tower.

19. Align the plate openings with the strut mount studs.

20. Confirm the plate sits flat against the mounting interface.

21. Reinstall the strut assembly according to BMW procedures.

22. Reinstall the upper mounting fasteners.

23. Use new self-locking fasteners where specified by BMW.

24. Tighten all suspension fasteners to the applicable BMW torque specifications.

25. Confirm that sufficient stud engagement remains after installing the reinforcement plate.

26. Reinstall all suspension, brake line, and wheel-speed sensor brackets removed during the procedure.

27. Reinstall the wheel and torque the wheel bolts to the vehicle manufacturer's specifications.

28. Repeat the process on the opposite front strut tower.

29. Inspect the installed components for clearance and proper seating.

30. Verify that the strut mounts are correctly positioned and secured.

31. Check suspension movement and steering clearance.

32. Inspect the vehicle for abnormal suspension noises.

33. Obtain a wheel alignment when required by the suspension work performed.

34. Reinspect the mounting hardware after installation according to the applicable service recommendations.

Important: Do not loosen the central piston-rod retaining nut or disassemble a loaded spring/strut assembly without the proper equipment and service procedure. Incorrect suspension disassembly can cause serious injury.

Compatibility Notes

• BMW E46 Platform: Intended for the corresponding front upper strut mounting arrangement used on BMW E46 3 Series models.

• OEM Reference 51717036781: The primary BMW reference associated with this reinforcement plate design.

• Earlier Reference 41114287198: Listed as an earlier revision in specialist parts catalogs.

• Front Suspension Only: These plates are intended for the front strut towers, not the rear shock towers.

• Left and Right Installation: The corresponding original plate design is suitable for either front strut mounting position.

• Two Plates Required: A complete front axle installation requires one plate on each side.

• Package Quantity: Confirm whether the supplied product includes one plate or a pair.

• BMW 323i / 323Ci: Earlier E46 models may be compatible despite falling outside the supplied 2002–2006 title range.

• BMW 328i / 328Ci: These models were produced before the later E46 model years and should not be listed exclusively as 2002–2006 applications.

• BMW 325i / 325Ci: Compatible original-style front strut configurations are documented.

• BMW 330i / 330Ci: Compatible original-style front strut configurations are documented.

• BMW 325xi: The all-wheel-drive E46 325xi is an established application.

• BMW 330xi: The all-wheel-drive E46 330xi is an established application.

• BMW 320i: Selected E46 320i applications are documented; verify production and suspension configuration.

• E46 Sedan: Compatible applications generally extend through the 2005 model year in North America.

• E46 Coupe: Certain compatible Coupe applications extend through 2006.

• E46 Convertible: Verify the original strut mount and suspension configuration before installation.

• E46 Touring: Selected Touring applications use the corresponding E46 reinforcement plate configuration.

• E46 M3: The plate may require trimming or other clearance adjustments when used with M3 strut mounts.

• M3 Coilovers: Coilover top mounts may differ from original BMW mounts; verify mounting and adjustment clearance.

• Factory XI Reinforcement: Some E46 xi models were originally equipped with front reinforcement plates. Inspect the vehicle before adding replacements.

• Existing Reinforcement Plates: Do not stack additional plates without verifying mounting compatibility and stud engagement.

• Standard Suspension: Compatible with appropriate factory-style upper strut mounts.

• Sport Suspension: May be used with compatible factory sport suspension configurations.

• Lowering Springs: Useful for reducing concentrated loads associated with some stiffer suspension setups.

• Aftermarket Coilovers: Confirm clearance with the upper mount, spring arrangement, and camber adjustment mechanism.

• Adjustable Camber Plates: Some camber plates may require plate modification or may not be compatible.

• Stud Length: Added plate thickness reduces available stud protrusion. Proper fastener engagement must be verified.

• Mounting Surface: The reinforcement plate must sit correctly against the mounting interface.

• No Welding Normally Required: The standard reinforcement plate arrangement is installed mechanically.

• Not an Exterior Strut Brace: These plates are separate from an engine bay strut tower brace.

• Strut Brace Compatibility: A compatible upper strut brace can generally be used in conjunction with reinforcement plates.

• Mushroomed Strut Towers: Existing deformation must be assessed and corrected appropriately before reinforcement installation.

• Cracked Sheet Metal: Reinforcement plates do not repair structural cracks or failed welds.

• Corrosion Damage: Rusted or weakened strut towers require proper inspection and repair.

• Accident Damage: Vehicles with prior collision damage may have distorted suspension mounting points.

• Suspension Noise: These plates are not a guaranteed solution for clunks, rattles, or worn suspension mounts.

• Wheel Alignment: Installing reinforcement plates does not replace a proper suspension alignment.

• Handling Performance: The primary purpose is structural reinforcement; measurable handling improvements are not guaranteed.

• Material Specification: Do not advertise a particular steel grade or thickness without verified supplier documentation.

• Surface Finish: Coating and corrosion resistance depend on the actual product supplied.

• Mounting Hardware: Existing fasteners may require replacement according to BMW service instructions.

• Not a Complete Suspension Kit: Struts, springs, top mounts, camber plates, and strut braces are not included unless explicitly confirmed.

• Not Genuine BMW: This is an aftermarket replacement unless its manufacturer and origin have been independently verified.

• VIN and Suspension Verification: Confirm the original mounting arrangement, suspension modifications, and vehicle production details before ordering.

Protect Your BMW E46 Front Suspension Mounting Points

The BMW E46 remains a popular platform for daily driving, restoration, and performance suspension upgrades. Protecting the upper front strut mounting areas is an important consideration, particularly on vehicles exposed to rough roads or equipped with stiffer suspension components.

These front strut tower reinforcement plates provide an additional layer of support between the upper strut mounts and the vehicle body, helping distribute suspension forces and reduce the risk of localized sheet-metal deformation.

For E46 owners looking to preserve their chassis, reinforce their suspension mounting points, or complement a suspension upgrade, these reinforcement plates offer a practical, factory-inspired solution when installed on a compatible and structurally sound vehicle.

Please refer to the “Fitment” section in the product description for compatibility details.