Hey guys! I just purchased my 02 z06 this week! I am beyond happy to have the car. It is a one owner electron blue with 14k miles. The car was built by RPM in dallas like 10 years ago, the mod list is as follows:

-Stage 3 CNC ported heads
-Fly cut Pistons
-Custom Ground Cam .244/.244 .612/.612 113 LSA
-Kooks Long Tubes + Kooks Catless x-pipe
-McLeod Clutch
-Varram Intake
-Aluminum Driveshaft
-4.10 gears
-Hardened output shaft
-Hurst Short Throw Shifter

I love the car and it runs hard, it put down 489whp on the dyno. The only issue is the car has a super loud noise coming from the shifter area in 5th and 6th gear on the highway. It stops when you let out of the gas. In 6th is its extremly loud. There is no weird rattles or anything, the noise is hard to describe, almost like a whine metal on metal noise but its not from the rear, its coming from where the shifter area is.

Could this be an issue with the Hurst Short Throw? I ordered a stock c6 shifter to see if it would fix the issue as I hate the Hurst anyway.

I do think the car needs a new tune as well, the idle on it is pretty crappy on intial start but once its warmed up it idles fine. I know the cam is pretty aggressive as well so I know that plays a part in it.

Any help is greatly appreciated!

 

probably the couplers or bearings in the torque tube

 

More than likely it's the rear diff. I'm going through the exact same issue right now. The whine increases with speed and is really prevalent in 5th & 6th at highway speeds. The noise works its way up the drive-line and emanates from the shifter area. It's my understanding that torque tube bearings would be RPM dependent, not MPH dependent.

Just search up differential whine and you'll see there's been several reports from owners in the past. Talk to RPM and have them upgrade you to one of their diff packages. The level 2 diff should be just fine at your power level.

 

is it in danger of breaking? Kinda exhausted the wallet for a couple months on buying it. It isnt my daily driver but I plan on driving it to work on fridays which is about 10 miles each way.

 

Is it still covered under RPM's warranty?
It can be hard to tell where noises are actually coming from on these from the drivers seat. The tunnel has a cover and sound can travel from front to rear and fool you.

If it is a bearing in the torque tube then I would think that you would have noise with the trans in neutral, engine revved with clutch engaged while parked.

Then if you are at speed while it is making the noise, what happens if you push the clutch and put it in neutral (the drive shaft shouldn't be spinning much)?

It could possibly even be a wheel bearing or broken parking brake shoe.

 

I have the same type of whine with the car being mostly stock and stock shifter. Whine started when we replaced the clutch pack in the diff. I kind of think it is an issue with how the pinion is engaging the ring gear in the diff. I figured when it broke I would know what was wrong. Four years latter I just turn up the radio or run the louder exhaust. Let me know what it is if you get it fixed so I can get mine fixed.

 

My stock diff whine pretty loud, been like that for 25k miles I have owned the car, but I only hear it with the top on and radio off, which 90% of my vette drive time is top off, which you can't do naturally...I think im gonna give this a try in the spring:


https://www.redlineoil.com/product.aspx?pid=147&pcid=4

 

I don't think it's in danger of breaking anything. I've been driving on mine for around 7k miles and still doing fine so far and I'm supercharged putting down 575hp to the wheels. You can see other owners on here seem to be driving with the noise just fine.

I'm not sure of the exact cause, but from what I've read other owners saying, it seems to be premature wear on the ring and pinion, possibly due to the gear oil never being changed (or not changed enough). Seeing how you've had your rear gears replaced though it does seem strange. I am by no means a professional though, so take that for what it's worth.

If you do want to eliminate the thought of it being a wheel bearing, there are a couple things you could do.

1. Jack up the rear and check each rear tire for play. Grab the tire by the 12 and 6 positions as well 9 and 3. Try to rock them back and forth. If you feel any significant play, chances are you wheel bearings are bad.

2. Take the car to an empty parking lot. Take some sweeping left hand and right hand turns with some pretty decent speed. Listen for noise. If you hear noise while turning left, that would mean a worn out right rear wheel bearing. Turning right would be left rear.

Although, wheel bearing noise and differential noise should be pretty easy to distinguish between just by normal driving. Wheel bearings are more of a growling noise, almost like you're driving a lifted 4x4 with huge tires. Differential whine sounds more like a roots style blower, not as high pitched but similar.

 

my aftermarket shifter is very loud tooo