V36 370Gt Low Frequency Pulsating Vibration Driving Me Nuts

[HIKAR1]

Hi guys,

Last week I purchased a 2008 V36 Sedan 370GT 7 speed Auto. Bought from a dealer at 56000kms. From day one I have been hearing this low frequency pulsating vibration and the faster I go the quicker the sound cycles. I'll be brief but descriptive here so I hope someone here can shine a light to this as I am totally stumped. The car still has the 3 months stat warranty but as everybody know dealer screws you around unless you pin point what the problem is.

Car is completely stock

The sound:

1. Low frequency (i.e when you drive over the fairly gapped ripple strip as you approach a toll gate)

2. Gets more frequent the faster you go - gets you nuts at 100km/h

3. It pulsates - loud none loud none

4. If I swerve the car to the left (all the weight on the driver side) the sound amplifies

5. It is felt through the car body

6. Steering does NOT shake at any speed (not wheel balancing)

7. Steering does NOT shake whilst braking (not warped discs)

8. Sound is irrelevant to engine RPM (I dropped gears or put it in neutral and the sound is still there)

What I have tried to rule out few possibilities:

1. Tyres - I originally thought it is because of the cheap chinese brand new tyres they put on during compliance. However, just then, I fitted another oem nissan same size wheels all round with michelin tyres that have NO issues. Sound is STILL there.

2. Re-check all suspension related bolts including tail shaft bolts, none were loose. Sound is STILL there

3. Wheel bearing - now this could be the debatable culprit. I checked for play, there was NO play. However I read online that even if there is no play the wheel bearing, it could still be in the early stages of failing.

4. Bushings - Car was on hoist, I checked all bushings for signs of wear or cracks. Nothing, everything was good.

5. Stuck caliper - Whilst the car still up, I spun all the wheels. Both rears has slight resistance (due to the drive train) but nothing was abnormal. Also been driving for a week, I would of noticed if the pads were cooking.

I pretty much did what a normal mechanic would do, bringing it to the dealer they would end up doing the same thing and do the catch 22 on me UNLESS I can sort of pin point where the problem is. Pretty stumped, please help!

Cheers.

Edited November 26, 2014 by kliono

[sonicii]

If you are getting a 'beating' effect (noise gets louder and quieter in a regular pattern), then there are 2 noise sources, since you have replaced tyres, my guess is wheel bearings.

[cav33r]

Id say wheel bearings aswell its the only thing that it could be seeing as though it happens more often the quicker you go and the gears have no effect on the noise

[The Max]

Bearings or tailshaft.

[HIKAR1]

Another update, I took the car on a long sweeping bend (freeway entry). Speed was 80km/h. Turning right this time, the noise disappear, however as I straighten up as I exit the bend the noise came back on. I did this going the opposite way as well (sweeping left) and the noise sure amplified......

Thanks for your input so far guys.

[sonicii]

Another update, I took the car on a long sweeping bend (freeway entry). Speed was 80km/h. Turning right this time, the noise disappear, however as I straighten up as I exit the bend the noise came back on. I did this going the opposite way as well (sweeping left) and the noise sure amplified...... Thanks for your input so far guys.

I would say definitely wheel bearings then!

Edited November 27, 2014 by sonicii

[HIKAR1]

Allright, bringing the car in to a workshop recommended by the AWN in few hours. I emailed them the list like above. See how it goes

[HIKAR1]

I would like to conclude this thread, it was the front wheel bearing.

Ordered the parts from rockauto in US and the workshop reimbursed me the money (oem nissan is ex japan 1 months wait). From the diagnosis everybody agreed it was the front drivers bearing, and the workshop changed just that. On the way home the same noise appeared. Got home, Luckily I kept the old drivers side wheel bearing and swapped it over myself as the warranty workshop is very far and no more noise/vibration!

Edited December 5, 2014 by kliono

[Ben C34]

What? You ended up putting the old bearing back in and that fixed it?

[sonicii]

I believe he means he used the bearing they pulled from the right side when they fitted a new bearing (which didn't fix the issue), and put it on the left (which made the noise go away).

Personally, I would be ordering another new wheel bearing and fitting it on the left, so you will have 2 new front bearings.

[Ben C34]

Doing anything to only one side of the car is always a bit silly. If one has worn the other side will be very close to wearing out.

[HIKAR1]

Perhaps you have missed that the car is still under the 3 months statuory warranty, meaning, they will only fix and replace what is broken and not take preventative measures. Once Christmas is over, I'll replace all corners. Shipping is a bit hectic during this period

edit: to think about it, I'll wait until the warranty finishes and hope the otherside goes during that period so they can replace it for free. Until then, otherwise, I'll do the above

Edited December 6, 2014 by kliono

[HIKAR1]

I swapped back the original drivers side wheel bearing and put the new one on passenger side.

[Ben C34]

True, I forgot about the stat warranty and that they will only do the minimum.

A shame all signs pointed to the wrong side of the car!

Can you get the bearing specs and go to CBC to get the other side from?

[sonicii]

If it is like the V35, you need to buy the whole hub, you can't remove just the bearing and replace it. The hub center is mushroomed at the end to prevent the bearing coming off.. Permanently.

[HIKAR1]

As to sonicii. The front bearing no, have to order the hub assembly. But the rear hub you can replace just the bearing itself, at least it was when I did it on my V35. Also I tried CBC, statewide, AWB, veales and repco they don't have a listing for it (said 350z for V35 and 370z for the V36). When you give them the Timken part number it is always ex-usa.

[sonicii]

As to sonicii. The front bearing no, have to order the hub assembly. But the rear hub you can replace just the bearing itself,

True.. but we were referring to the bearing replacement for the other front bearing, so as you say, you need the entire hub.

I believe for the rear the bearing comes with the mounting bracket, and you just need to press the hub out and into the new one. Or you can buy the entire assy for ease of replacement if you don't have access to a press.