Vibrations, shady explanation

[subspd]

I have a vibration right at 70mph that I have also recently noticed... but don't see any thing loose, and then I also have a cold vibration only when accelerating. Related?

 

[subspd]

Funny thing is on my Jeep I never would have even noticed or cared but this car is so much nicer I hate to have any vibration that wasn't there before...

 

[uHu]

What is that a picture of???

Adding on to several good bits of info here...
According to TSB EG038-05, this is "Weight, No. 4 Crossmember Damper".
This TSB is full of different noise killing stuff, covering all US LCs from 98 to 06. Included is a list of which remedy to apply to which VIN, together with lots of illustrations and how-to's.
I can e-mail the TSB as a PDF if anyone is interested.
Title of TSB is "EXHAUST BOOMING AT IDLE"

 

[spressomon]

Warning: Practical Dynamics (ME) stuff below.

That is a tuned mass damper.

Believe it or not, a good OEM (like Toyota) does quite a bit of engineering analysis and testing, to tune the entire vehicle system, including the chassis, for reduced vibration & noise.

Sometimes they find a resonant point in the system, where a judiciously-placed, calculated mass will damp that point, attenuating (quieting) the entire system significantly, for a particular range of frequencies. So they judiciously place a mass there, and lo, the entire system is attenuated, since the natural frequencies & the inputs are harmonics of the range in question. This results in a quieter vehicle with less vibration in the system.

Interesting, eh?

Once they confirm where they want such tuned mass dampers, they design production parts for this purpose, to be included in the production vehicle build.

That particular mass damper is one of the largest I've seen. (But then again, I don't spend that much time crawling around inside vehicles anymore...)

I'll leave my mass dampers in place, thank you. (And thanks Toyota, for designing & building them in!)

Regarding the dealer BS about your noise/vibration problems: I feel your annoyance. Sounds like BS to me. Good luck.

Good info indeed. You must be an engineer!

 

[Tinkerer]

Good info indeed. You must be an engineer!

" 'Engineer': One who devises "

 

[calamaridog]

I'll leave my mass dampers in place, thank you. (And thanks Toyota, for designing & building them in!)

Good info, however, I don't need anything hanging down on the trail that doesn't have to be there. I got hung up on that damn thing once and it went into the junk pile.

As I'm sure you know, there is an engineered solution to everything. My solution to this particular problem was to remove the object in question

Besides, once you change the dynamics of the vehicle with larger tires, sliders, bumpers, and heavier suspension, who's to say the dampener has any effect on the dynamics of the vehicle anymore. It may actually be causing a new vibration now

 

[Tinkerer]

Good info, however, I don't need anything hanging down on the trail that doesn't have to be there. I got hung up on that damn thing once and it went into the junk pile.

As I'm sure you know, there is an engineered solution to everything. My solution to this particular problem was to remove the object in question

Besides, once you change the dynamics of the vehicle with larger tires, sliders, bumpers, and heavier suspension, who's to say the dampener has any effect on the dynamics of the vehicle anymore. It may actually be causing a new vibration now

All true, all true. Except the last part - don't confuse a damper with a dampener. (Common mistake) Big difference.

I may be in the minority in this forum, dunno: I do not plan on modifying my LX. Not in the least bit. (Used to have a K&N air filter, but that's history now, after reading in this forum...and I don't think synthetic oil or co-extruded Bosch wiper blades count...) So my dampers, and everything else, should pretty much function as designed.