BMW Chassis Reinforcement Kits & Parts for BMW E46 M3 S54 (1999-2005)

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Made in the USAAs much of an "Ultimate Driving Machine" it is, many BMW models unfortunately suffer from weak points in the chassis. Over the years we have uncovered many weak or failure-prone areas in the chassis and have developed our own reinforcing solutions for them. And we continue to be the leading experts on BMW chassis reinforcing. Failures can come from a number, or combination, of causes: improper maintenance, age and mileage, poor design, environmental factors, poor repair work, and over-stressing modifications. The longer you let your car go without repairing or reinforcing these areas, the closer it gets to crumbling apart. Our chassis reinforcement kits are designed to first identify potential weak points and then strengthen and reinforce the existing design.

Most of our kits are not labor intensive although welding is usually required. If you suspect your chassis may have structural problems we recommend taking it to a well-known bodyshop or restoration shop. (find out who your local BMW dealer uses - we sell many of our kits to dealer-authorized repair shops). Making the preventative fix simple and effective is better than a long and complicated repair after the failure. Our kits are not usually used for fixing existing damage (only your body shop can determine the correct course of action). But our kits have been proven under extreme conditions on racetracks around the world to prevent many of the costly - and dangerous - chassis problems.
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Turner Motorsport - Corporate Logo
T#:631
Part#: TDR4675F99
In Stock
Sale - Save 77% $ 79.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.25 USD
Free Shipping on orders $49 and up
Sale - Save 77%
$ 79.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.25 USD
Free Shipping on orders $49 and up
Made in the USA The motor mount area on a subframe is one of those easily-forgotton areas that may be hiding a serious problem. The subframe on the E46 has a gusset ('ear') welded on for the motor mounts. These gussets take the stress of the motor mount as the engine torques (more upgrades = more torque = more stress). Worn motor mounts only transfer more stress to the subframe. Unfortunately, the sheetmetal will fatigue over time even though the gusset is reinforced from the factory. Check for cracks along the welds and an uneven plane from the subframe to the gusset. A total failure of the guesset will shift your engine to the side and forward, taking out many other components along the way and leading to a very costly repair.

The next time you replace the motor mounts, oil pan gasket, checking your oil pump nut, or any other time you drop the front subframe, you should install these reinforcements. This kit comes with steel reinforcing plates that are welded to the underside of the guesset as well as plates to close off the bottom of the gusset for extra strength. Instructions included.

This item fits the following BMWs:
1999-2005 E46 BMW 323i 323ci 325i 325ci 328i 328ci 330i 330ci M3
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