I recently installed the Super Now differential collars on the lower part of the differential bushings. Instead of replacing the factory rubber bushings, these collars effectively reduce the play in the OEM rubber bushings.

Due to some rust on the bolts connecting the mid-pipe to the axle-back flange, I chose not to disconnect them. Instead, I removed three exhaust hangers from each side, allowing the entire pipe to drop down a few inches for access to the bolts. The installation process was straightforward.

The impact of these small collars is surprisingly significant. Power delivery is now much more immediate and predictably progressive. I also noticed a reduction in noise under wide-open throttle. There is a slight increase in noise transmitted through the driveline into the cabin during partial throttle at low RPMs, but the benefits far outweigh this minor drawback. The consistency and responsiveness of power delivery have improved greatly.

I purchased the collars through Top End Motorsports, who provided excellent customer service. They promptly addressed my inquiries about the compatibility of the Think Design upper collars with the Super Now lower collars. As suspected, it's not advisable to use both. The Super Now lower collars are quite thick and already compress the bushing significantly. Installing the Think Design upper collar would not only be more challenging but would likely increase noise levels while offering less reduction in slack. The upper collar would introduce more metal-on-metal contact without the same bushing compression as the Super Now lower collar.

Overall, I'm extremely satisfied with this upgrade. It has made my car feel more performance-oriented, cohesive, and luxurious.
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2013 GS350 AWD LUX, spare tire and tools delete, Tuned by Loi: 91 octane tune, Trigga Spec: Tundra 76mm throttle body w/spacer & coolant delete, Ported lower & upper intake manifold, aFe: Takeda stage-2 pro 5R oiled CAI, Apexi: Midpipe w/ceramic coating, Revel: Axle-back w/ceramic coating, High Spark: Premium coilpack, NGK: 94122, Konig: F3S 18x8.5 35+, Toyo: Proxes Sport A/S 235/45/18, RR Racing: USRS race edition, Air/oil separator, Ventilated CF badge, KYB: Gas-A-Just w/AVS all around, Stoptech: Sportstop cryo sport drilled rotors all around, Akebono: Performance ultra premium front, ProACT ultra premium back, Super Now: Lower differential mount collar, Spoon Motorsports: Subframe collars front, Anti-Gravity: Li battery, Non-stop tuning: Al water pump pulley, Mishimoto: Al lug nuts, DEI: Cool-tape, Xpel: XR plus nano ceramic window tint all around