LS430FL

I got my 2011 LS460L about a month ago. I have noticed that when coming to a stop in either forward or reverse I am hearing a thumping sound that appears to be coming from the right rear wheel area. The best way to describe it is sounding like a thump or like a radio bass sound. If I press down and stop then let the car creep up a little you can feel as though it is catching on something as it rotates. I took it to dealer a couple weeks ago because I just got it from
them and they said they put new rear brakes. It was a comp service so I didn't get any paperwork. I was suspecting rotor warp but the mechanic was there with me and said he didn't see any high spots so not sure? I should also mention the brakes squeal loud when pressing on them in reverse only not forward which is interesting. Any ideas you guys have would be great so I can give them to the Lexus service tech when I take it in again next week.

Littleguy

For the noise you may be looking at the brake acuator:

https://www.clublexus.com/forums/ls-...-bulletin.html

As far as the squeal, it's also common on the LS460, a lot of us suspect it is due to blank rotors:

https://www.clublexus.com/forums/ls-...ls-460l-4.html

Hope this helps!

LS430FL

Thanks for the reply. I have read a few threads on the brake actuator. They all seem to hear some clicking from front of car. This is a thud or thump, which is weird.

superdenso

You should rule out any driveline slop. Make sure there is no traffic. Get the car up to 50mph, put it in neutral and apply the brakes. Pay attention to see if you still feel and/or hear the thump.

LS430FL

hmmm there is an idea. Lexus didn't even consider that I don't think. I'm going to try that.

comotiger

But don't you have to apply the brakes first to shift out of D? Be careful and do not slip into R!! Have some physical barrier that would prevent you from shifting into R. You guys are brave, but I would not do this! I can only imagine that you will destroy your transmission if you accidentally shifted into R at 50 mph...

LS430FL

comotiger, I was a little worried about that too....I wonder how common driveline slop is. The problem is really just annoying me every time I am coming to a stop I hear three or four thumps from the right rear.

Nospinzone

Well I'm not going to test this, but I am pretty sure that the car will not go into reverse above a certain speed, like over 5 mph or less.

roadfrog

Me neither, but you are correct Sir.

comotiger

I am no mechanic, but would this be some kind of electronic device (sensor) that prevents shifting into R or purely the inability of gears rotating in one direction to abruptly switch direction?

superdenso

Not many cars require a brake to shift out of "D". Be careful. Further, the dealer can change the brakes and address the thumps, just be persistant, and cordial 1 (800) 255-3987.

See Neutral Coast Down->
http://www.autoserviceprofessional.c...remlins?Page=2
http://www.popularmechanics.com/cars...o/a76/1272406/

Nospinzone

Here, I just went out and tested it.


At the end they say it must be electronically controlled transmission, but older transmissions had a hydraulic lockout.

superdenso

Nospinzone, you're my hero Moreover, if anyone reads this thread and and of the following applies: gets nervous about accidentally shifting into neutral, needs to look at the selector first, may sellect some other unintended gear, may do something else that may be dangerous to themselves or others; the dealer or a mechanic should be commissioned to do the procedure.

LS430FL

Car is headed to dealer tonight, will report back on their resolution to the problem incase anyone else finds they have the same issue.

LS430FL

Car has been at lexus since friday, still no word on what they are doing...