ryanis350F

Hey all,

model: 2014 IS350 F sport AWD

Wondering if anyone else has this issue. When I go over a medium sized bump at moderate speeds, there is a loud thump coming from the trunk area. My trunk is empty and everything looks fastened down securely. I can not figure out what it is. The only thing I notice when I check the trunk, If i hit the center of the floor board, it imitates the sound almost identically. I checked the spare tire... everything..

In my trunk is the floorboard and the lexus carpeted mat. Maybe something else is missing?

Anyone else noticing this noise?

Thanks Ryan

doodlebug

Read this thread and try the parking brake trick and see if that fixes it.

https://www.clublexus.com/forums/is-...4-is-350f.html

a790

If you'd let me out I'd stop banging on the trunk, just saying...

AndrewP930

same thing happened to me. I tried the parking brake method and tightened my spare tire and it eventually went away.

Lindenlea

very witty fellow canuck

theoryguy3

1) Parking Brake
2) Spare tire
3) wheel jack

Was #3 for me

ryanis350F

ill try the parking brake method. But my noise isnt a tick or a rattle in my case. This is like a thump. Low tone. like the opposite.

ryanis350F

Tried the parking brake and it didn't work. I'll take a look at the trunk stuff again. Can someone verify something for me please. The trunk should have the Lexus logo carpet on top then another lining piece below the carpet and that's it correct? I want to make sure I'm not missing a piece

Sonik

Check your rear shocks for abnormal residue when compared to the others. I had a factory blown driver rear shock within 8k miles. Made a thud when I went over bumps because the car was bottoming out.

Another way is load the back with passengers and go over a speed bump, if its more noticeable definitely check your shocks.

Good luck.

ryanis350F

Im gonna bring it to the dealer. Was the shock under warranty?

JB5674

I have some thumping in the trunk but its from a 12" Apline type R soon to be 2!

link13

This is rad.

Jagstyles

I've been having the same thump over bumps coming from the trunk. Will check out the suggestions listed above and report back.

wiliu0

I had this issue too, but it was only after I installed different wheels and BC coilovers, have anyone experienced this with coils or new wheels?

TED_FR

Hi Ryan,

Yes this problem has been reported to Lexus since late 2013.

It happens on F-Sport IS with regular suspension only. According to the dealer, it looks to be related some way or another to too stiff dampers.

Depending on the car, the noise can be very loud.

The answer we got from Lexus France was : "works as designed, the cars comply with Lexus factory standards" .
That's a design flaw and as such, dealers cannot do anything about it. That's where we stand today.

I just cannot understand how Lexus could let this problem heavily impact on the brand reputation.

As per today, the only choice left to us over here is to sell the car. (one already did it).

I'm pretty sure Lexus Japan will come up with afix one day, the question is ... when ?