Front end squeak/chirp when I apply the brakes on a bumpy road

[tbreen3272]

Why does my front end squeak/chirp when I apply the brakes on a bumpy road? I have a 2002 Toyota Avalon XLS with 187,000 miles on it, but in great shape. The squeaking/chirping noise has been going on for about 30,000 miles during which time I have replaced the struts, sway bar bushings, sway bar links, brake pads and shims, and tires. The noise doesn’t occur until I have been driving for a while (10+ miles). It doesn’t occur unless the brake is applied. The rotors seem fine – not warped but possibly close to minimum replacement thickness. I can drive over the same bump with no brake applied and the noise doesn’t occur. It seems like I have to be going at least 10 mph for it to happen. It is not the traditional brake squeal due to bad pads, shims, etc. It doesn’t seem like a bearing issue because it never happens unless the brake is applied. And it isn’t a long steady squeak (like a loose belt or rotors being scarred).

One additional problem– probably not related but I would love some advice here too – but when I replaced the struts, links and bushings the tell-tale ‘clunking’ noise came back within a day. Jacking the car up would make it disappear for a day. My mechanic suggests that the mounting plates at the top of the strut should be replaced too, but that will cost as much in labor as the original strut job! Any ideas?

[csaxon]

The mounting plate is usually the culprit for your "clunks". Toyota issued a TSB recommending the redesigned plate to customers who complained.
The squeaking may be a sticking caliper with a slow release after brake application.

[tbreen3272]

Thanks for the feedback. Now that I am paying attention, some additional observations as I have put the car through some tests.

The squeak is not related to the brakes being applied after all. It actually occurs when the front end pitches downward such as when I apply the brakes and hit a bump. But I can also create it when accelerating quickly in reverse or driving from a flat surface onto an incline (like a driveway entrance that pitches up considerably from the street) - in neither instance are the brakes engaged.

So I think all my problems are related to the suspension. I bought Gabriel Ultra Struts and Duralast Sway Bar Links and installed them myself about a year (20,000 miles ago). The chunking noise recurred within days and the squeak...well I don't recall when it started - before or after the new parts went in, but it has definitely gotten worse over time.


Do you think this could be related to the strut mount somehow or are the parts I bought at Autozone inferior?

Also, where can I find TSB's online?

[csaxon]

Gabriels have a good reputation. Toyota redesigned the strut mounts so that may be your problem.

[tbreen3272]

Hopefully the last question. $140 for the pair from AutoZone (Duralast brand) with the free coil tool loaner vs. $200 from the Toyota dealer and no tool? Is it likely Duralast has the latest design mods per the TSB or I am safest spending the $ at Toyota for the official part and finding the coil tool elsewhere?