2007 and later Toyota Tundra, Land Cruiser and Lexus LX570 trucks are prone to a scraping or rubbing noise from the rear brake at high mileage, especially if operated in areas with high road salt useage.  The scraping noise is often caused by the rear backing plate rubbing on the rotor, causing the rotor to machine it’s way through the backing plate if left too long.  Here’s a backing plate from a 2011 Tundra with the condition:

Tundra Rear Backing Plate Rubbing

Tundra Rear Backing Plate Rubbing

In the above, the left side of the backing plate has worn through.  Here it is closer:

Tundra Backing Plate Closeup

Tundra Backing Plate Closeup

Rust builds up behind the thinner backing plate that protect the parking brake assembly and the thicker stamped metal that secures the brake caliper and wheel bearing.  This causes the thinner backing plate to be pushed outward into the rotating rotor.  Looking at the backing plate in profile makes this apparent:

Tundra Backing Plate Rust

Tundra Backing Plate Rust

And on the other side:

Tundra Backing Plate Rust

Tundra Backing Plate Rust

The rear backing plates that house the parking brake have a tight tolerance to the rotor.  This is to protect the parking brake from road debris, but when the backing plate swells from rust the above is the result.

Toyota has released and updated backing plate for the Tundra with the above condition to help prevent it happening again.  While we’re not sure the Land Cruiser or LX570 have update parts available, replacing the backing plates has proven to be the best solution across the board.  Attempting to hammer back or grind down backing plate may prove a short term fix, but CARspec has seen the noise return after a short time once the backing plate swells further from more rust.

Replacing the backing plate is not a simple job, requiring several Toyota-specific specialty tools to remove and install the rear axle bearings to the axle in addition to cutting the bearing races from the axles once it is free of the bearing housing.  Even with multiple Toyota rear axle repairs under a technician’s belt, the 10-12 tons of force needed to correctly repair this condition and tight tolerances of the axle’s installation can be a challenge.  Disassembling the axle incorrectly results in a bent axle or heavy fluid leaks.  Often a combination of heat, a 12-ton press, and an air hammer is needed to diassemble these rear axles when rusty.  CARspec stocks multiple copies of Toyota’s rear axle press adapters because the total force required to properly disassemble a heavy duty, rusty Toyota rear axle frequently damages the tools (or the press).  While we normally encourage the DIY crowd to take a shot at their own repairs, the above is extremely challenging and time consuming repair that should not be undertaken by most DIYers.

If you would like to have CARspec take a look at your Tundra, Land Cruiser or LX570 for the above condition don’t hesitate to give us a ring at (952)426-4798 today!