Hi guys, would really appreciate your wisdom on this one. My beloved 2006 RL is at 16,000 miles. Recently I began to notice a certain low-frequency clunking sensation that I feel through the steering wheel rather than actually hear. It seems to happen mostly when passing over dips in the road. It's very subtle.

Differential diagnosis (doctor-speak for "What could this be?")???

I've thought of a broken or leaking McPherson strut, loose or broken steering components, not sure what else. I don't trust the dealer much, so having some ideas before taking it in would be very helpful.

I don't think this is normal. It sort of reminds me of the chronically arthritic feel of an older American car. Not what I want to experience in my Japanese-built luxury sedan!

Ideas, anyone?

 

Maybe the cold weather has made a tire go slightly out-of-round???? Does it happen at highway speeds after several miles?

 

Of course you are in LA so no cold weather!

 

Perhaps a suspension bushing?

 

A tire seems to be the first logical choice, bad belt, etc. Move front tires to back, both.

 

Happens primarily at low speeds going over dips and bumps. Thought of tire issues, though this feels more mechanical, if you will...a deep metallic "thunk" that is different from the normal initialization of the antilock brakes. It is so subtle and so intermittent that I know the SM is going to say "cannot reproduce" and label me a crank. But it is worrisome. Bushing, maybe. Thanks for the replies and keep puzzling this one out, please!

 

dont rule out a bad tire. I have had more than a few tires where the belts in tire have seperated internally...one being a Michilein.

 

If you rule out the tires and wheels (I hit a deep pot hole at 65 mph and bent a wheel; no suspension damage), maybe you have a slightly warped brake rotor.

Have you rotated your tires yet?

 

Yep, tires last rotated at 12,000. I've been even more attuned since posting this, and realize that when I am applying brakes lightly I sometimes feel the clunk via the brake pedal too. That sort of lends credence to the warped rotor idea...or the tire.

 

Rotate the tires again, front to back, then report back.
If it is a rotor, you can feel a pulse in the pedal if you brake from about 40 mph brakes VERY lightly.

It is very unlikely a bushing.

 

Don't think it's an out of round tire. You've driven 16000 miles on an 06. Like suggested, rotate your tires. If the noise is still there, you can pretty much rule out the tire.

Don't think it's a warped rotor either. You'll feel the steering wheel shimmy constantly under braking and feel it on the brake pedal.

I'm still leaning toward bushing or something in the front suspension/steering components. Ball joint that's wearing prematurely, suspension mount point, broken washer between suspension components, etc. Reason is you said it primarily happens over dips and bumps and it sounds metallic. The components that go though the most stress during dips and bumps are suspension components.

For what it's worth, years ago I had 93 SHO and I was experiencing a very subtle "thunking" noise, mainly when turning in one direction (can't remember if it occurred when I turned in either direction). Since I belonged to the SHO Registry, I found out that a bunch of owner's had the same issue. Turned out Ford used a plastic washer between 2 steering arms (or suspension arms, can't remember which now.. It's been 13 years!) and the plastic washer broke and was missing. Hence, the thunking noise when the 2 arms moved that 1/16 of an inch (or so) and smacked into each other when under load...

 

Thanks guys...now the BIGGEST challenge...getting time to take it in to the dealer!

 

One other thought, VoDoc, is a wheel bearing. They'll do that, too, and since you feel it when braking, it's a possibility.

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Warped rotors do not clunk the make the brake pedal and everything else vibrate when you apply the brakes. First thing to check is lugnuts to rule out a loose wheel. Other causes, are loose or damaged brake or suspension components. A common source of a clunk while braking or with suspension impacts is a bad shock absorber. If you are adept at playing mechanic, lift the wheel off the ground (with a floor jack) remove it and inspect all the suspension components (bushings an so on), make sure that the brake caliper is not loose, if the shock is leaking fluid that is an obvious sign. Another trick is to grab the wheel while the car is on the ground and shakes it sideways vigorously, a good couple of firm kicks also works, sometimes, that can help you locate the noise. Of course look in the engine compartment for some other loose stuff. As mike stated above the bearing is another possibility, a good way to detect it is the shaking /kicking procedure. However bearings usually give you a low pitch woo-woo sound before they klunk. Hope this helps!

 

The loose lug nut is a good theory. It reminds of a day way back when my friend got his VW Rabbit GTI back from the shop. We were driving around and kept hearing a clunking sound from the front end. Our solution to try and diagnose it was for me to get out of the car and listen for the clunk as my friend drove around me in circles braking and accelerating.

I'm not sure how he eventually found out what the problem was (I think he went back to the shop and they found their little "mistake"), but it was traced to loose lug nuts. I'm surprised we didn't try putting me on the hood to get an even closer listen!

We felt pretty silly for having continued to drive the car all over town, despite the noise. I could just imagine a wheel flying off.....

Bottom line, check your lug nuts if only to rule something out.

 

Funny, I woke up at 2 am thinking about loose lug nuts (they DID rotate the tires, maybe forgot to torque 'em). Are you guys clairvoyant??

Again...the next challenge is to find the time to take this puppy in.

 

Might be the lug nuts but it would require all but 1 to be loose (the wheel would rotate slightly around this single lug bolt, with the lug bolt as it's center) with the clunking be constant. You should feel it slapping the other lug bolts all the time too, not just at bumps and dips.

Hence, I don't think it's a lug bolt either. But hey, if it is, it's an easy fix!

 

Not the clunk of a bad driveshaft universal joint? I remember driving an old Caddy Limo that had that problem, and they replaced the u joint, no more clunking, though I honestly cannot remember whether the clunk was manifested through the steering or not.

 

I would be really surprised if we had a wear item, like suspension or driveshaft with this low of miles on an Acura.
Please let us know what they find.

 

Agreed. Please let us know what the cause of this mystery is...

 

Any update?

 

Thanks for asking! Out of town this week, driving the minivan with the family, enjoying the togetherness but missing the RL.

Lug nuts are OK, the clunk remains subtle, intermittent and no worse, and I still have not had time to get to the dealer! This day job is SUCH a pain...

 

I get something like this through the steering wheel on both my '05 RL and on my '94 Honda Accord. This usually happens when driving slowly over uneven ground such as my 1/2 mile unpaved driveway. It feels like something in the steering might be loose, but is so consistent in both of my Hondas and now on the Acura that I consider it normal and characteristic of a Honda product. '05 Acura is now over 100,000 miles and the '94 Honda is over 461,000 miles.

 

The slight looseness, or play if you will, that I've always noticed with my Honda products, seems to be associated with up and down motion of the wheels on uneven ground.

 

Duh....I've found at least a partial solution to this mystery.

When I took the car in at around 12K miles for B service with tire rotation, I asked the dealer to inflate the tires to recommended pressures. Of course they didn't.

I didn't pay much attention, as the pressures were reading close to spec on the MID. Today I checked with my digital gauge and found that they were actually about 4 psi low all the way around. I inflated them to 1 psi above spec (33 front, 31 rear--remember this is PAX).

Not sure yet that this totally solves the issue, but I immediately noticed at least 80% improvement in the clunking or excessive play that I was sensing via the steering wheel.

Thanks to all who've expressed opinions in this thread.

 

"I asked the dealer to inflate the tires to recommended pressures. Of course they didn't."

I had the brake TSB done a couple of weeks ago and asked them to check the (PAX) tire pressures as well. When I got the car back , the TPMS (which I've found to be spot on with my Accutire gauge) read between 36 and 36 PSI (vs. the recommended 32, 30). Odd because even most "normal" tires are inflated to 32 PSI or so. Fixed it when I got home.

LL

 

With my 2003 TL when the tires were slightly underinflated made a light clunking noise when the car sat cold for a day or so when i would first drive the car. I always equated the issue due to the tires conformining to the floor and it would take several minutes for the tires to retain their proper shape.