Buzzy Vibration at certain RPM's..read before buying!

Many of us tried that in neutral and we did not get any vibration. Myself included. My driveshaft was within normal limits. There is a TSB for the driveshaft for
Deceleration 30-10. This involves adjustments for the driveshaft angle.

 

could some one try driving the vehicle in manual shift mode and keep the transmission in 3rd or 4th gear. does the vibration occurs?

 

Well well well so im not the only one with weird vibrations and buzzing inside cabin on pedal and steering wheel , truck vibrates on idle u can see it vibrate then when shifted onto neutral it goes away seems odd too me it feels like a tranny problem like in my old toyota pickup that had a bad tranny

 

I'm also experiencing this buzzing sensation at the 2000-3000 rpm range especially at low speeds and I'm only at 600 miles. Just scheduled an appointment for next Monday 3/13/17 with the dealership here in Flagstaff, AZ. From what I've read here sounds like the rubber engine mounts and/or an overly-rigid exhaust system could be the cause of this? Has anyone heard about a TSB for this? Can't believe that a truck I paid 40k for is having these issues. Not sure if I wanna wait it out for Toyota to come up with a fix. Considering getting into a 4Runner 4x4...

 

4Runner? You should not spend any more money on a Toyota until they fix this.

 

I have a manual transmission. Happens in 3rd or 4th as well.

There is no TSB, you will get the "it's normal" response. It happens in my truck, many others, and even new ones I have driven fresh on the lot. I am comfortable saying it is either an oversight, design flaw, or just poor standards given to the NVH team.

Unless it results in excess fatigue damage down the line (which is highly unlikely for this case, and anything would be many many miles down the road), it will remain a nuisance rather than something toyota actively pursues to fix. Unless of course we can get enough people complaining to corporate or it starts hurting sales numbers.

I agree, it is incredibly annoying, I notice it every single time I drive the truck. I just wish I could get a toyota NVH engineer in the truck with me and ask them if they are truly proud that their company approves of this.

 

@aero90 I went to the dealership today, told them about vibe issues and Doobiewah's interaction with Toyota engineers from Denver back in Jan 2016. One year later, there is still no fix for this. They told me to bring the truck in anyway so they could at least document it and have it reported to Toyota. At least they were being honest and actually seemed to want to help. Service manager told me things like this take a year or even two sometimes if enough cases are documented. Also test drove a super clean 2nd gen trd off-road with 40k miles (no vibes)...considering trading in...

 

I'm gonna contact Toyota and see if I can't get some information regarding the research/testing being done to resolve this issue. For all we know they may have concluded it to not be an issue worth addressing.

 

I've heard a lot about how the vibration felt in the steering wheel and floorboard during acceleration may be due to how the exhaust system is set up. Today I went under the truck and checked the exhaust mounts and bushings, along with other points under the driver side cabin (after the engine was warmed up).

A few observations regarding the exhaust system:







The whole exhaust seems to be having some heavy vibration for idle. I'm willing to bet money that this vibration gets worse in certain RPMs. I don't think the exhaust being mounted to the tranny like this helps either. Since the exhaust is right under the floorboards it makes sense the vibration is felt in the floorboard area. Steering rack and column did not seem to be vibrating at all during idle. It would be interesting to get the truck on a dyno and see how the exhaust vibrates under certain RPMs. I'm also willing to bet money fluid dampening engine mounts would help relieve this issue. I will be running ethanol-free VP racing premium octane to see if that helps smooth out the flow...I think vibration got worse when I filled up with some crappy ethanol blended fuel. Thoughts appreciated...

 

Do think harm would be done removing the screw holding the brace to the transmission and taking it for a short drive to see if this reduces the vibration? I haven't looked at mine lately to see how much support the brace is providing.

 

It would be fine for a short drive, however, I think many pages back someone may have already tried it. I don't remember it making a large difference.

Main theory so far is Engine Mounts and/or exhaust resonance. There could also be a design flaw where external vibration sources (engine/exhaust) is exciting a natural frequency of the body, but if that is the case, that is some really piss poor engineering. I'd be really surprised if that slipped through the cracks.

The exhaust as the source theory can be tested with either a helmholtz resonator or mass dampers correctly implemented at the right places (the latter method is a bit tougher without a model of the system and would require a lot of trial and error).

The engine mount as the source theory we are kind of stuck on. The Lexus ones don't line up the same so it would require fabrication of new mounts.

Basically both theories cost a lot of time and money which understandably nobody wants to have to devote to it. It is easier and cheaper to just trade it in.

 

gregbo2401 2.5RS | 04 Forester XT 6 points 2 years ago

"Sound is a wave vibration that ranges in frequency and wavelength, or size of waves. When going through an exhaust, the shape of the exhaust can act as an amplifier for certain pitches. Example: at 2500 RPMs, you will hear the exhaust much louder than at other times. This can even be compounded more by traveling through the floor and into the cabin of the car. This can be combatted with different shaped exhausts, or most commonly a resonator or muffler, which work to absorb the sound waves and quiet the exhaust. Resonators, being smaller, can be used at strategic points in the exhaust to still retain a raw loud motor sound, but to be done properly would need a lot of testing/sound engineering or a lot of trial and error/luck."

This makes a lot of sense. Looks like it really could be an issue with the exhaust design. Makes sense that people who have replaced their exhaust with an aftermarket. Installing a resonator may also help.

 

This was what we worked on with my issue last year...the cost to fix it was too expensive.

 

Yeah hopefully Toyota will figure it out and come out with a TSB for it. Exhausts should be engineered to resonate at a frequency outside what is typical for that car's engine to generate or they must include components to cancel out that frequency. If there really is an issue with the exhaust design, then it will have nothing to do with the engine mounts.

 

One member here installed this [dual] America Thunder exhaust which he says eliminated the vibration

https://www.youtube.com/watch?v=0hmGJsNc0dg

https://www.realtruck.com/flowmaste...haust+System&gclid=CI2e9YfEydICFQ1YDQodPgEGGA

Not enough data to confirm this was the fix.

 

I wonder if adding a wazoo of dynamat to the floorboard would help. This stuff works pretty well. I had annoying vibration/noises on from a Liebherr refrigerator (big bucks German refrigerator supposed to be quiet ). Used a bunch of Dynamat Extreme and it quieted that bitch down a lot.

 

Rigid mount to transmission and/or engine is nothing unusual. The engine and transmission sit on a cushioned mounts, so these should absorb bulk of vibrations.

 

Some of us have been waiting since the thing release in late 2015.

 

Yea but then you'd have to drive down the road sounding like a lawnmower.

 

They will tell you they never heard about this issue before.