[Zero Six LE]

Originally Posted by shaggyusm

How could the ABS make a clank? What part of the braking system could sound like that? Sure it's not the clutch-fan? ABS? I just don't know about that. I've had MANY vehicles 8 with ABS and I've never had that sound. These are the vehicles I've had (wife included): '92 S-10, '95 Dakota, '96 Maxima, '01 Tundra, '06 Silverado, '01 Camry, '03 CR-V, and '06 Trailblazer. NONE of these had this sound. Is the ABS booster made out of tin in a Frontier? I have '07 Frontier Crew 2wd SWB Automatic and it does it too. Well, if all of yours does it too, then I guess it's nothing to worry about regardless of what it is. Please post a comment if you have any machanical failures as a result of whatever makes this sound.

It's a ABS self test for sure. Late model medium and heavy trucks do a self test every time you turn on the ignition key. That's to make sure that all the modulator valves work in the ABS. I'm sur that our trucks do it to ensure no moving parts are stuck that would prevent them from working under the right conditions. If a fault were to occur during the self test, the ABS light will illuminate.

Read on page 5-29 in the 2006 Frontier owner's manual.

Self-test feature

The anti-lock brake system consists of electronic
sensors and hydraulic solenoids controlled by a
computer. The computer has a built-in diagnostic
feature that tests the system each time you start
the engine and move the vehicle at a low speed in
forward or reverse. When the self-test occurs,
you may hear a .clunk. noise and/or feel a pulsation
in the brake pedal. This is normal and is not
an indication of any malfunction. If the computer
senses any malfunction, it switches the anti-lock
brake system off and turns on the ABS brake
warning light on the instrument panel. The brake
system then operates normally, but without antilock

assistance.