townsville

I have this strange creaking almost a sharp cracking noise coming from the rear part of the roof near my head when I go over some bumps. I have tried all the usual methods posted to this forum; lubricating roof rubbers, adjusting bump stop under package shelf; adjusting roof height using the grub screw adjustment; nothing seems to work. It almost sounds as if the noise is coming from some of the hard plastic roof trim but I can't seem to pinpoint it despite using foam padding, silicone spray etc..

Anybody come across this before ?

MDames2

iTrader: (1)

This is fairly common on these cars. My wife's 2003 has some of these noises as well. I have Lexus technicians work on some areas of the roof on several occasiions. It has helped minimize the rattles. As these cars age, the various hinges, rubber, plastic, and other parts lose their shape and become less flexible. A certain amount of creaking noises is inevitable considering the flexing that occurs with the top. After the work done by Lexus on our top, it is very manageable and only slightly annoying at times.

mandyfig

I wipe down the rubber gaskets all around with AS303 protectant every couple of weeks. And it has worked for me. Recently I have started to hear some creaks. Time to wipe with AS303 again.

But I agree, as time goes by, mechanical components will shift ever so slightly and it is inevitable that these will result in squeaks.

townsville

Tks guys, I have tried a number of roof rubber lubricants. Glycerol works well, silicone lube is also good (more for pinch points and hinges) but I agree - Protectant seems to be the best. I recently used a cheapie and it worked very well. I will try the AS 303. Tks for the tip!

hoffy5

Have you ever used Dupont Krytox, I have some in grease form and liquid! Used on rubber seals quiets the car down!!!! The Krytox is expensive, I use it on My other car, BMW Z4 convertible and door seals!

Jabberwock

This is what I use - pricey but worth it to preserve rubber and seals -

Patek14

What are you using to lubricate the roof seals? If the sound is a rattle like, its probably not related to seals. If it is sqeak/creaking like, sounds like seals to me.

I use this product - Gummi pfledge. Wurth rubber care also seems well regarded.
https://www.autogeek.net/1z-einszett...are-stick.html

The other thing is, how many seals are you actually treating? There are a LOT more rubber seals than just on the roof's panels. All the components of the roof in the back and tons of rubber weather stripping everywhere. there are tons of surfaces.... at least my mine [not a SC, but its all the same for the purposes of this discussion]

hoffy5

I know the sound you are hearing! Something just came to mind, however not sure if it is worth the Risk or time! The rear window glass seal may be the culprit! I am going to lube the seal to the frame of the Window to see if that helps. My Daughters Toyota had a very similar noise, the Glass Window in the rear was where I tracked this similar creak noise to. If you could fit in the back Seats, drive around, listen and Touch, push on Glass to see if the noise goes away! If so, then I would ask a Glass Expert if they believe changing the Window Seal would rid the sound? Also, another area to test, put some upward pressure on the Headliner and see if the noise goes away?

Maybe someone on the forum can chime in and tell us if they had the noise/creak sound shortly after purchasing the Car new? Or did the sound get more pronounced due to age? Flex to the roof panels over bumpy Roads--Maybe one or all Rubber Seals would need to be replaced to rid the sound. However the cost would be expensive!

Bob

hoffy5

Project # 3 on Saturday, Trying to quiet the convertible top, here is what I did, I will post pictures.... as soon as I get my Key/Remote fixed:

1-Purchased 3M Auto quieting tape from Amazon 3M 5430 Squeak Reduction Tape, 0.25" x 5yd (1 roll) (The tape is very nice to work with). I had read on the Web some TSB from various car manufacture, they use this Tape for Squeaks, Rattles, Creaks
2-Open roof half way to install the Tape
3-Installed, I did not measure, the Tape from left to right the entire length of the interior roof Panel, not on the inside, but the upper portion of Panel that would close down and meet the Rear Window Panel.
4-Did the exact same on the front of the interior panel, again, the location of the tape installed runs the entire length so when the Top closes it mates with the panel above the Sun Visors!
5-On the front there is to metal clamps that lock the Roof, I put tape a couple of turns around them since they contact with metal!

The Tape is very slippery and is almost invisible, Also you do not see the Tape when the Roof is closed!

Now the Test, I went down some nasty' Roads we have in NC

Result, I could not believe that the sound is gone

Installation time ,1-hour with help from wife

Bgw70

this is very good information!
So when you were driving with the top up, the roof would make noise?

hoffy5

I believe that the noise was more toward the rear, I believe the rubbing due to rough roads makes the roof shift, hence the 3M says, hey I am ok, just let it slide, I am slippery!

B-

Harold57

Very interesting. My top will squeak a little when the weather is just right. I haven't quite figured that combination yet but it seems to be in the middle temperatures between 50ish and 75ish°F and to the humidity levels. (Very inconsistent from a casual monitoring standpoint.) Once it gets outside the "zone" it goes quiet again. I suspect that mine may be those rubber stops somewhere at the bottom of the window (I've only seen pictures of them, never searched them out) that some have said that they've adjusted them to make a similar noise go away. So far it hasn't gotten annoying enough for me to try to find time and do something about it yet.

hoffy5

Hi Again,

Yea, this fix is amazing and works!! Lexus should have a TSB, I know the car is old, however I am glad I found the fix, again I will post detail pictures when I get my Car back from Lexus!

hoffy5

Temperature change in North Carolina this past week has been all over the map! I decided to let you all know that the Fix I posted is working and my car is dead silent over Bumps, Humps, whatever! Roof is no longer flexing!
I will get up pictures for those who want more detail!

Finally a post I can give back to CL

Bob

Coleroad

A couple of things came to mind this morning on this subject. I was thinking more about the torsional rigidity of the chassis. Could one or more of the braces under the car had the bolt/bolts shimmy loose. Two, if not would a quality one piece strut brace fix the flex. Was just trying to think of the root cause so hopefully there wouldn't be an alignment issue later.