good stuff...

 

strangely but odd.... my 2007 G35 Sedan shaked violently at 75+ MPH... i couldnt figure it out...hood would shake...steering would shake... got new tires, got everything checked out fine!....i took it to get an oil change.. they checked underneath.. and the underside cover, where the plastic pieces covers the oil pan, drain plug etc...it was missing a bold that held the plastic plate in place... so they added a bold and made sure she was strapped on good... took it back on the road.. and it was smooth sailing... at high speeds air would get caught down there and would make the flap shake alot!

it sounds strange but it worked for me. something simple.

 

Update. I have since replaced the rear rotors which helped some but still not 100% better.

I have done approx 8-10k miles since my last post. Vibes are starting to get worse again.

I blame most of the vibes on the tires since it gets better as the tires warm up.

Most likely i will have the tires rotated and balanced again soon. Tires still have a lot of life left on them so i wont be replacing any time soon.

jraborg86, the underbelly pan is an interesting fix. I wouldnt expect one bolt to cause such an issue. I plan to switch mine out for an aluminum aftermarket unit soon. Maybe this will help even though i know mine is firmly attached.

Thanks for all the input guys.

 

yea mine does the same thing. but only when i apply the brake though. i have no clue why

 

Just thought i would give you guys one more update. I recently approached the 100k mile mark and decided it was time for a spark plug swap. To my surprise the car was quite a bit smoother. Again i wouldn't say its 100% but anything helps.

I never thought spark plugs could make a difference. Then again it could all be in my head. If you are getting close to the 100k mark you might think about changing them out. You might be surprised. There is a couple good DIY's on the site. Should only take about an hour and is well worth it.

 

Same problem with my 04' Nismo. Thought it was my new rims. Had them rebalanced. and car aligned. Put stock wheels back on and still shakes just not as bad. Now creaking from front end. Def going to replace the compression rod bushings. Post the after effects.

 

Compression rod bushing or check the. Upper and lower control arm bushing..

 

im having a same problem with my car i have no idea what it is. i changed the break pads and still have the vibration at 70ish. infiniti g35x 74k 2004 no wrack not a rebuilt title plz help.

 

i have

 

Ok everyone,not to be the bearer of bad news but i have read all of your posts and the common denominator here is that most of you drive X models. The only thing that none of you guys have thought about is the front driveshaft...that is more than likely your problem. This is a common problem on any of these junk X models. I work on them every day. I love the G35 and I also own a 04 sedan, but the X model is a terrible design. Jack the passenger side of your car up and crawl underneath it,look at the front driveshaft where it bolts to the front differential. If it has a rusty dust residue on it,go ahead and order a front driveshaft for it. I replaced 4 last year and all of them had come apart and busted a hole in the side of the bell housing on the transmission which is very ugly. There is no scatter shield to protect the trans in the event of the front u-joint coming apart. Don't let time pass because this can cause a very expensive repair if it breaks. The drive shaft is already $700 plus not counting the damage to the transmission if it busts the bell housing.. I really hope this helps you guys..Jason

 

No X model here. Waiting on my bushings. Hopefully it will resolve this issue. Will post results later.

 

sounds like a warped brake rotors. happened on my old civic, when slowing down from 55+ the thing would shake horribly! I ended up going to autozone and getting new rotors and pads. pads had a lifetime warranty and the rotors had a 1yr warranty. it was about $160 for 2 civic brake rotors. so probly something nasty like $300+ for new G brake rotors. you can always get your current ones resurfaced too, its cheaper sometimes but eventually your gunna need to buy new rotors. GL

Is that only when braking? or is it a constant vibration? if its only while braking, get new brake rotors. if you can change out brake pads you can change out brake rotors, its only a couple more bolts after doing your brake pads

 

Bushing install went smoothly. Used Energy Suspension bushings. Didn't fix the problem 100% but it did help. Ended up installing some Stillen rotors off of my buddy's 350z and new pads. Problem solved. It was a combination of warped rotor and blown out bushing causing my problem. Now if I can only get my hood to stop shaking when driving on the interstate.

 

i have had the same problems also anything above 60 my passenger seat shakes and it gets worse as my speed increases but after about 85 it goes away. how much did you spend for a compression rod? you wouldn't replace both?

 

I quickly read through everything, and didn't see any mention of a warped wheel. My girlfriend has a bent rim, and it causes her car to start sharking between 65mph and 80mph, but is less noticeable after 80+. Confirmed this when I put snow tires on her car, and it went away entirely. I even notice it with my X: the rims it came with sport my summer tires, and there is noticeably more vibration on those as opposed to my after market snow tires/rim set. Infiniti/Nissan is known for making soft rims; I was actually warned about that as I bought the car, and was told I'd need to buy some new rims after a while.

I wonder if it could be something that simple...because if so, it would still persist after replacing the tires (as the rim(s) would be the problem). If you know anybody around you with an X, see if they'll let you throw on their wheels for a quick spin down the highway.

Good luck.