Our 2013 RX350 makes an annoying thunking noise, coming somewhere from the rear underside of the car, every time you come to a complete s stop, e.g. at a traffic light. I had a test drive with a mechanic from our Lexus dealership, and he told me that every 2013 RX350 he ever drove made that noise. Is that true? Can anybody else comment if they had the same problem and how they got Lexus to fix it?

 

Call his bluff. Am sure there are enough 2013 on the lot, sold or in for service, to sample to see if it does the same thing.

 

FWIW, like many topics this has been discussed previous. For example:

https://www.clublexus.com/forums/rx-...013-rx350.html

 

I had the same problem in my 2012 RX350. Went to the service dept. took one of the mech. with me to identify the noise he said that it is common in the RX. Because of the suspension in the back. ?? well that's what he told me, I'm no mechanic lol.

 

Late model F150 trucks have the same issue, I drive a '10.
Tranny is a 6 speed auto, electronically controlled.
When nearing a stop, tranny is being shifted back to # 1.
Depending on the modulator or vacuum points the ECM is looking for, the tranny will actually shift from 2-1 at the instant it comes to a full stop. The gear change, even while just crawling, transmits a change in torque to the rear differential, via the drive shaft. This travels down the shaft, thru at least two sets on U-joints, thru the pinion, across the differential & then eventually out to the road wheel.( RX may have move U-joints or CV joints as I believe it's independent rear ?)

Everything under the truck is tight as a drum but the late down-shift shows occasionally.

 

Truck was serviced today. Dealer found a TSB on the late-shift. Tech. plugged the laptop in, made a couple adjustments, issue resolved. No more late shift with a bump/clunk/ noise just after a stop.

I'm sure Lexus/Toyota has had more than one complaint. Might pay to search for a similar TSB.

 

Truck? Are you referring to your RX? The late shift is the best explanation I've heard on this problem. Thanks.
I remember back in the days of front-engine, rear wheel drive, stick shift cars, when the drive shaft u-joints wore out, there would be a clunk.
Our Highlander with 140K is starting to downshift at slow speeds noticeably. Time for an NX?
Ray A.

 

Sorry about the confusion. The Ford F150 was serviced yesterday. I had posted earlier that this series truck has the same issue as some of the later RX cars. Ford's TSB was entitled "Late Down Shift................".

 

Hi, does anybody have any update on this? It's been a year since I took the car to the dealership and I was told it's normal. The noise is still there and drives me nuts anytime I drive it. The car is due for service soon, and I will probably take it to them and tell them this will be the last Lexus I ever buy if they don't fix it. It really kills all the sophistication of the car and makes it feel very clunky to drive.

 

Try it again at the dealer level. Get another '13 off the lot & have the sales staff tell you it's normal.
Something is up, likely a simple fix but a bear to find it.
Dealer falls down go to Lexus direct. I'll bet the dealer would be a little more interested.

 

Something I'd try just to narrow down the issue:

Place the transmission shifter in "S" Mode and manually downshift yourself at various speeds as you're slowing down to a stop. For instance downshift to 1st at a normally higher speed than if it were in D, like at 15 mph instead of about 5-7mph in D. If the issue is exactly still there and occurs exactly when you downshift to first, then the issue is likely with the first gear and the thump occurs regardless of speed. If the issue doesn't occur in S mode at all even at the lowest speed of 5-7 mph, maybe it's the brakes or something else. On my 8-speed (F-SPort), no issues in D or M (S) mode.

A couple other things to pay attention to:
1. Does the issue occur when reversing?
2. Do you have AWD? If so, engage the 4-wheel lock (button ahead of the armrest), make sure you stay below 25 mph to not disengage the permanent AWD, then come to a stop. Any difference?

 

Well, I am pretty sure it has nothing to do with tranny. It happens when car settles down again after stop. If you come to a stop very slowly, there is no noise.

 

Hmm, sounds like the brakes perhaps. Without repeating too much (see thread as RX330inFL posted above), I had a clicking/clunk noise at times and it was due to brake pads shifting as per the Lexus service tech. It wasn't often and very loud and mostly happened when reversing. No action was taken at that time and it was not flagged as a safety concern but as "normal".

My IS had a similar clicking and was reduced after they lubed it. See this thread hopefully this can help you for your next scheduled maintenance soon even though it's not the same car, but perhaps can inspire the techs to help resolve the issue.

 

Ok, got some interesting news on this thunk noise from back. I mentioned the thunk noise to the service advisor when I brought the car in. Didn't have much hope that anything would happen, but the service advisor was actually able to find a TSB for this problem: TSB L-SB-0104-14. He said it applies to certain 2010-2015 models. They replaced some parts at the rear brakes, looks like mostly on the RR side: shim kit, fitting kit, mounting, and a shock assembly as well.

Loh and behold, the noise appears to be gone now at my first test drive. Very happy! I hope this is the ned of the story and it won't come back again.

So anybody else with this issue, don't let them tell you it's normal. Use the TSB above and get them to fix it.

 

Appreciate your following through and updating us -- and even happier it appears your problem is resolved! Woo-hoo!