I've been away from this forum for a while but I can let you know my LC's symptoms soon returned i'e after the 70 mile journey I made. The car went back in and this time the brace was welded to the inner B panel and hey presto the knock is gone.Apparently, and according to the lad I spoke with, a very easy fix but clearly also very effective.

 

It looks like I'm having a VERY similar issue. The dealer said it's either a spot or pinch weld that came loose, which is causing the squeaking noise in the rear of the vehicle which is noticeable when starting and stopping. He indicated that it's not too big of a deal so he's going to coordinate taking it to a body shop on Monday to confirm. I really hope the fix is as easy as yours @Brinylon .

 

From what I have gleaned, this problem tends to be more prominent on the opposite side to the driver so in other words, you would hear it in your right ear but it can also manifest itself on the drivers side albeit I have not seen any reports of that over here. This, as I understand it, is the ultimate fix and trust me you'll kind of miss that clunking noise, bizare I know, but just wait and see.
Do keep us posted because I for one would be very keen to know how you got on.

 

@Dtddt did you ever get this fixed? If so, can you please post the resolution and how much it cost? 9 hours seems extensive for the repairs that some others experienced, so I'm curious what it finally cost you.

 

Why do you think I'd miss the clunking noise? I've only had it for a few days and it drives me nuts, so I'm curious as to your perspective here.

Also, you're giving me hope that this can be fixed relatively easily despite me having to find a body shop to do this (my local dealer no longer has a body shop)!

 

I know the lack of knock is weird but when you've lived with it for nigh on a year, it almost becomes part of the cars soundtrack. Don't get me wrong it also drove me nuts!!

I've no idea what the repair actually costs but Lexus UK were quick to advise no charge before the work had even started. In part this would most likely have been down to the previous "free" fixes they tried and I genuinely cannot fault their determination to resolve this issue regardless of cost. Additionally the approved body shop is just up the road from me and when I saw the car parked outside I "watched" it via my tracker and saw it being jockeyed around before disappearing under cover i.e. actually into the body shop. It was left in there over night and came out first thing the following day whereupon it was then driven to my dealer.
When I spoke with the body shop on another matter, I quizzed them about what sort of a job it was, and as it happened, I spoke with the lad who did the necessary. He was totally and utterly unfazed by it and said it was a very simple job and took no time at all. As I remember it was seat out, B pillar trim off and then in with the welding torch. If someone is quoting 9 hours, then that someone is, or at least so it would seem, taking the ****!! I would imagine the fellow who did mine had probably never done this before such is A, the rarity of the car and B, the rarity of the fault but nonetheless done and dusted in no time.
I'd be most interested in how you get along and I sincerely hope you have a similar experience to me.

 

What year is your LC?

 

First registered to drive on the UK roads in July 2017, which I think in your eyes makes it a 2018 car?

 

could be either depending upon when/what month Lexus determined the MY for the ‘18’s.

 

The knock in my car coming from under the passenger seat area towards the passenger door. It is driving me nuts!

My car is 2017 build coupe. For the first 2 years the knock used to be only when the car flex over extreme angle ramps. Now it is even worse since i can hear it whenever i accelerate, take a turn or even brake.

can you guys confirm which side are you hearing the knock? Passenger or driver or both?

Anyone found another source other than the B-pillar weld mentioned in a recent post? Thanks

 

The knock/click or call it what you will, has from my forums experience originated from your passenger side (for left hand drive) or in my case driver side for UK right hand drive. My understanding is that it could also originate from the opposite side, but it seems from the evidence, it is usually your passenger side.

The initial "fix" will be to grease and tighten various bolts securing the brace to the B pillars and on the body work. This may well cure the problem for some but it tends to variable whether it works or not. The weld approach is a 100% fix and frankly from what I've seen and experienced then it is a permanent solution.

Hope this clarifies matters and btw, the symptoms you describe are identical to those I used to have..

 

@Northstar1 - Your description perfectly sums up my experience, and Brinylon sums up the fix options.

I've asked Lexus corporate if they'll address this as a goodwill gesture since my car is under warranty, but also have a body shop waiting to do the non-weld repair, which will run about $1k USD (about 11 hours of body work, which to me seems to be the highest quote I've seen here, but I also don't have a lot of time to shop this around given how obscure it is).

I should have more information in a few days and will keep this thread posted on what I find out.

 

Looking forward for the good news, kindly ask the dealer and the body shop for pictures to share with us later. Ill drop my car at the dealer within a week too.

 

If it were me I’d want a Lexus dealer to do the Lexus prescribed repair. Hope they cover it for you.

 

is the a common issue? will all lc have this issue over time?