Noise I can't figure out - Please Help!
 

I have searched but couldn't find anything that is similar to my issue. Therefore, I decided to post up here to see someone can help me to figure it out.

Start up the engine in the morning, put in the first gear and drive slow. When the RPM gets up to about 1500, the noise (it's almost like grinding sound) occurs while I am driving. It's coming from the engine, seems to be somewhere under transmission. It only happens between 1500 - 1600 RPM interval. When it pass 1600 RPM, the noise goes away until I park the car with engine off for abour 2 hrs. After 2 hrs, turn on car and drive, the noise happens again. It only happens one time after starting the car.

Thanks for your helps.

Heres a thought...Dont drive your car below 2000 rpm. Problem solved :)

never heard of that before.... hows your oil level in your trans if its just change it out with new stuff or just top it up hope this helps never heard of this problem good luck

I will put the new trans fuid this weekend and hopefully it will solve the problem. Seems like it only happens when the engine is cold. I had my slave cylinder replaced last year due to the recall. Do you think it's related to this issue?

Thanks.

Hows ur engine oil level?

I get that too.

Could you please post any updates on this issue?

What year is your Z? HAve you had any grinding when shifting quickly? (ESP from 4th to 5th and 5th to 6th)

Sounds like the beginnings of when both my trannys died on me. (under warranty thank god!)

Status updated
 

I have changed the trans fluid, diff fluid and engine oil, but the noise is still there. Somehow, I feel the noise somewhere behind the gas pedal.

My car is '07 with 61k miles. I dont have any grinding when shifting, it shifts very smooth in all gears. I know that I'm out of warrenty, so I called Nissan. They told me just bring it to a stealership to have it diagnosed and call them back to find out what they can do about it. I doubt that they will pay for it. As far as I know, I will have to pay $90 for diagnose. What's your suggestion? Should I take it to the stealership?

Thanks.

Mine is 2004 and has 50k miles.

The tranny does not grind at all in any other gear, except the 1st or 2nd gear after the car was off for a while, just like 350Speed says.

My fear is that they will check your car for $90...but they might not find any problems because the tranny won't be grinding anyways...

You may get them to drive a car after letting it sit there for 2 hours, but the grinding happens less than 1 second and it won't happen again after.
Not sure if they will be able to find any problems.

Under warranty, sure they will just replace the tranny, haha...

Come to think of it, I remember having same noise for my previous RSX...People at club RSX said it was the heat shield rattling. I never bothered to check.

To 350Speed: Check if the sound comes on 2nd if shifted early. I shifted at low RPM and the sound came on 2nd gear. it might not be tranny!!! ;)

To 350z.z053,

Yes, it happened the same thing when I shifted into 2nd gear before 1500k RPM. Other than that noise, it shifts very smooth in all gears, so I don't think it's tranny. I will try to take it to the asian shop around to have it checked out. At least they don't charge for it. :-)

My second (yes second) tranny was replaced for a similar noise. Shifted fine, but when cold (esp when cold outside too) for a split second it would sound like there was zero fluid in there. Sometimes it would do it while shifting, sometimes just cruising at <45mph. They spent a week with my car trying to duplicate it. Once they did they (Nissan) determined it was the pilot (thrust) bearing. They threw another CD009 tranny in vice rebuild.

I see...
Do you have to take tranny out to fix the pilot bearing?

In that case, I am out of luck without warranty :dunno:

Thank you for the info.

My co-worker drove it yesterday, and he said the noise did not come from the trans. It came from somewhere in the engine bay, behind the pedals. He told me to look into the brake system.

Any inputs on this?

Thanks.

Here is what I tried this morning.

- Started the car
- Shifted it in reverse and rev it up 1500rpm (didn't hear any noise)
- Shifted it in first gear and drove (didn't hear any noise)

Does anyone know what the problem is?

Thanks.

Still sounds like the "pilot bearing" issue we talked on the phone about.

"the pilot bearing keeps the input shaft on the trans center and does not allow axial movement of the input shaft, thus saving the trans bearings some wear. the seal is what it is, a grease seal. the pilot bearing is like any other bearing, it needs grease to work properly and not chew up the input shaft. the seal keeps the grease in the eccentric shaft's dish for the bearing and keeps the grease from spinning out of the pilot bearing onto the pressure plate or clutch disc."

I am debating between to replace or not to replace the pilot bearing...although I still lack of understanding on what its function is.

It is really weird because I now can feel the vibration on accel pedal when sound happens...hmm...

Thank you very much for the information, halfass872.

I thought trans warranty is 60k miles.

I've been researched online, and it seems like to me it's pilot bearing.

Thanks, halfass872.

It is. I believe 5yr/60,000mi from date of production (Not date of first title)

No Prob!!:thumbup:


I didn't really get a good understanding of what it did either, but you gave a damn good explanation!

From my understanding it must be a beotch to get to. They gave me a new tranny vice go into my old one to replace it, eventhough it's only a $15 part. That being said, you may want to just pick up a new tranny if you are sure thsi is your issue and they won't replace it due to being out of warranty.

FWIW they made it sounded like you could drive around like this for a pretty long time without any real mechanical issues, it would just make annoying noises every once and a while.

But definatly pay to have the dealer determine exactly what it is. I'm no professional, i've just had three transmissions replaced and they all had a different problem so i'm kinda used to the "bad noises" and what they mean.