It has 110k miles now, always ran mobil 1. (I know that will be asked)

Especially when cold, it feels like all the vibration from engine is transfered in the frame when it is revved up or accelerating. It feels like it has solid motor mounts. Or maybe an exhaust pipe is up against a frame rail. There is annoying audible noise that goes with it it. It started at about 90k miles. Seems like its getting worse. If you listen to the engine with the hood up and rev it, is sounds fine. But inside the car under acceleration, its nasty. Anyone have this problem and fixed it?

 

So, im going to sell this car if I cant fix this. The vibration and noise over 4000 rpm is annoying enough that I dont romp it any more....which was the sole purpose of the car. Its gotta be the mounts, right? The rubber is old and hard?

 

check the motor mounts. If you can't tell then have your mechanic look at it. If you're having a good time with the car why sell it when fixing the problem is so much cheaper..., unless you're looking for an excuse for a new vehicle...

 

I had that problem and it was the LSD in my case. Might wanna look into that.

 

I looked at the motor mounts. They "look" good. Did the power break thing, the engine doesnt move much. So, the mounts arent broke. I checked the exhaust system for frame rub points. Looks good. In my experience, the mechanics are useless idiots. Not even worth the time for them to look at it. I checked for TSBs. Nothing. The vibration and noise is getting worse. The car now has 134k miles. You think the rubber gets hardened over time? I could just change the front mounts, see what happens. They are over $100 each. Was really hoping someone has fixed this issue already

Disappointing if this car is only a pleasure to drive for the first 100k miles, then it drives like a datsun B-210 after that.

 

OP, you mentioned how the vibration transfers to the frame or feels like it. Have you got under the the car and inspected the transmission mount? For me, while replacing my stock transmission pan for a Level 10 pan, I went ahead and removed/swapped the transmission mount (stock for winter/urethane for summer). In doing so, I had a loose bolt that would have added in overall vibration. Try it. Remove the mount and inspect it/replace it. Retorque the mount to the transmission and then brace/bracket to the frame. If nothing else its peace of mind.

Another idea is the driveline itself. The driveshaft could be unbalanced for a variety of reasons. But after 134K miles, the driveshaft could be sagging at the center bearing mounts a little causing an excessive joint angle, thus the vibration. FSM DLN-4.

 

Is the noise like a metalic sound?
Is it consistent with the revs?
It is worse better when it's colder outside?

Hard for us to diagnose it without hearing it.

I had a noise from 4k to about 6 k under full throttle when colder outside on my '08.
It came from the left side of the engine. I removed reinstalled and re tightened the intake on the driver side and no more noise.

 

I am glad I am not the only one that experiences this. Mine too when cold makes the same sounds. This only happens in cold temperatures below 50°. The more throttle you give, the worst it sounds. I have tried to diagnose it but its a hard sound to replicate. When the car warms up, the sound lessens and becomes more like normal.

What LSD issue were you referring to in the post a few posts up?

My car is a 2008 5AT with 65,xxx miles. Stock suspension and this noise has been around since I bought the car from 19,000 miles from the dealer. Its quite annoying. When my car friends ride in the car they are like "wtf is that sound". I shrug

 

I think one of the intake resonators on my car was touching one of the metal surfaces because if I hit a dip in the road while the noise occurred it would get louder - consistent with the dipping motion or momentum. I took the entire intake off and reinstalled it. Twisted the resonator slightly away from the wheel well in the engine bay. Then it was like new. I don't know if that was it or if it was something else that I moved in the process but it worked for me. I also noticed that the seal between the airbox and where the air enters in front of the car to the air box was not very tight before I took it off and reinstalled it which I imagine (again just guessing) was further exacerbated by the colder temperatures

 

I will have to try that this weekend. I have Stillen GEN 3 intakes on right now but I had the noise even when I bought the car. How ironic would it be if the resonator was the one making the noise...

 

I'm here because I have the same issue. It seems to have recently popped up. I agree, if the car is cold you hear it on acceleration from 3000 -> 5000rpm. Once I've been riding around for a while it seems to go away. I did recently clean my throttle bodies so I wonder if your fix is what it is.

To the garage!

 

Did this ever get solved? Mine's got it!

 

Sorry for resurrecting a really old thread but I'm having the exact same issue as the OP and for the life of me I cannot figure it out. I know it's a long shot but anyone have any suggestions?

 

So, I bought aftermarket “OEM” hydraulic mounts a while back but never put them in. They are not accessible on this car. The manual says to drop the subframe. So I put it off. The car has 196k miles and the vibration is horrible. You feel it in the steering wheel and the seat, way worse when cold. Its from the engine for sure, not drive train. I finally changed the mounts today. Didn’t need to drop the sub frame, just have to be creative to get the top 14mm nuts off the motor mount stud. (Shorty box end wrench, and a pry bar to crack it loose) Changing the mounts helped quite a bit. Car is way less annoying to drive. But, its still not Nearly as smooth as it was. Very sad.

 

I’m having very similar symptoms, especially upon hitting dips in the road. It almost sounds like a rotating part is making contact with something stationary. I tightened the air intake tubes yesterday and reseated the air filters in the boxes but I’ll take a deeper look at the entire intake assembly tomorrow. Thanks for the tip.
just had a replacement engine and new motor mounts installed last week along with a solid flywheel and new clutch. The stiffer mounts and solid flywheel are probably adding to the resonance but I doubt they’re causing it.