The Problem
The stock center support bearing carrier holds the driveshaft in place with rubber so thin about 20 lbs of force moves it from center to the end of its travel. While that???s great for making sure no NVH makes it to the cabin, the stock bushing is extremely prone to failure, especially in harsher climates and on higher-powered cars. Even on the best-kept cars, the stock rubber bushing sags, dry rots, and cracks by the time it???s 10-15 years old. When the bushing lets go, it leads to excessive vibrations and clunking which can damage the transmission and rear diff. To make matters worse, the stock carrier is molded onto the center support bearing, leading to costly driveshaft replacement.
???
The Solution
This upgraded unit keeps the driveshaft firmly in place at all times, and its polyurethane construction ensures it will never wear out. The thick bushings ensure the driveshaft cannot move from center, maintaining driveshaft alignment at all times.
The Bushings
Two options are available for the bushings, both of which are many times stiffer than the stock bushings. We???ve paid close attention to the NVH levels associated with this upgrade. We???ve engineered custom isolator bushings that separate the carrier from the body of the vehicle and mounting bolts to substantially reduce NVH levels.
The street bushings absorb most of the NVH from the drivetrain. Expect some light NVH at some speeds in the form of a soft hum. With a modified exhaust or windows down you???ll probably never hear it. Most NVH is heard between 20-40 mph. At highway speeds it fades away.
The track bushings are for those who want no-compromise drivetrain performance. These may create a substantial amount of cabin noise throughout the low range, again fading at higher speeds, but not entirely. Not sure which is for you? Try them both, they???re interchangeable!
Installation
Installation doesn???t require removal of the driveshaft. The 2-part design clamps around the OEM bearing. The old carrier must be removed, so a cutting tool is required.
The video below is from the B5, but the C4 follows the same order of operations. Remove forward tunnel brace, lower exhaust, remove heat shield, remove rear tunnel brace, cut away OEM carrier, trim rubber around bearing, install new carrier (do not reuse the spacers between OEM carrier and body), put it all back together.
Fitment
C4 A6/UrS4/UrS6
Part Numbers
Full Assemblies
Street - C4001A0-S
Track - C4001A0-T
Both - C4001A0-B
Bushing Packs
Street - BSH04A0
Track - BSH04A1
