KJ Nguyen

Sorry for the delay in posting the info. I have been car shopping to trade the 08 RX for a MB or BMW. Well I did not take any photos but I can share my words. You need to apply some Dynamat Extreme or some other brand material to the top, side and front of the brake booster, (the large round part behind the master cylinder) also apply 2-3 layers over the check valve itself (the plastic "L" shaped piece with the rubber hose connected to it.) The strips on the booster are 2.5 in. wide x 7 in. long (sides 3 req.), 4 in. x 7 in (front 2 req.) and 1.5 in x 4 in on the check valve itself (2-3 req.). I had to remove the air filter housing (2 screws and a clamp, easy) to access the booster because my arms were to big. The whole job is no more than 30 minutes. If Lexus HQ reads this they should be able to implement a similar solution in production and give the dealers a TSB for RX already on the road!!!! :chairshot:

Junxus,

Thank You for your detail description of the solution. I will give it a try.

KJ

I used a scope and found the noise to be coming from the brake booster check valve. The dealer agrees and will order one. I put some Dynamat on the Brake booster and the check valve. The noise is gone!!!!!! :) I am happy now!

Hi JunXus,

I own a 2005 RX350 and experience the same problem. I wonder if you could share how you resolved it using Dynamat. Perhaps posting a picture of what you've done. Appreciate it.

KJN