Good Afternoon Gents (Ladies),

I've been running into some issues with my 2001 C5 Z06 lately.

Here's a low down on the car:
- I'm the second owner
- 63,xxx miles
- Very well maintained
- Motor performs excellent
- Trans shifts very well (minus Reverse pop-out )


The car has developed a vibration since I purchased the car last year (car had 45,xxx miles when I bought it; Vibration developed around 60,xxx)

At 40MPH the car gets a "pulsating" vibration that feels like it is coming from the rear of the car. I can hear a slight vibration noise that corresponds with the pattern of the vibration that I can feel through the steering wheel, seat and pedals.

When I make a right turn in the car (large bend on the highway traveling at 60-70MPH) the noise/feel seems to go away. When traveling straight and taking a left turn, the noise stays and sometimes worsens. This leads me to believe it might be a wheel bearing.

BUT, sometimes when driving the car down the highway it feels VERY rough. Like the car is jogging down the road, but the jogging is also temperamental like the pulsating vibration mentioned above. The odd part about this is that the car only does it under deceleration and coasting, not really acceleration as much.

The car also feels rough at high speeds (100mph+).

I have 18x11.5 CCW SP505 in the rear with 315/35/18 Toyo TQ's and 18x9.5 SP505's in the front with 255/35/18 Potenzas. This is the second set of wheels, and fourth set of tires I have had on the car. The vibration has not gotten better, or worse, with the new wheels/tires.

I've also had the tires/wheels balanced on the car currently 3 times just to verify. Nothing has changed.

I've checked all four wheels for wheel bearing play (good 'ol grab-n-shake method) and haven't felt anything indicating and issue.

Could it be a wheel bearing and just one of those ones that I can't diagnose with the shaking method? Tie-Rod ends? TT coupler?

I know that's a lot to take in, but I just can't seem to narrow down what the issue might be.

Thank you.

 

rubber couplers in the torque tube can do it. in fact a few places in the drivetrain can do it, clutch being another. all you can do with vibration issues is troubleshoot them and re try. ideally another set of tires and wheels should be tried just to make sure you don't have flat spots or something weird going on. past that it's trial and error testing. try to keep track of what brings it on

 

Sounds like a torque tube rebuild kit is in your future. Check our rpm transmissions website. In fact call them, I'm having similiar issues on my car and they gave me some great advice based on what I described was going on.

 

Thank you for the response. The clutch seems to feel okay when going through gears, etc. But sometimes when leaving from a stop if I have the clutch engaged and am releasing it to take off there will be a whining noise coming from what seams like the center of the car. It doesn't always happen, just sometimes.

Awesome, I'll have to see if I can snag a second to give them a holler! Thank you.

Also, none of the noises/feelings occur until about 40-50MPH+. Anything before that is very smooth.

Driving to work this morning I noticed I get a lot of the higher speed feelings in the steering wheel.

 

If your going to install new TT couplers then I would really think hard about going ahead and changing the clutch. I needed a new trans and my clutch felt fine but I went ahead and installed a new clutch while everything was apart.

 

agree on the clutch/slave/master. seals age, things wear. this if one of the more expensive c5 restoration maintenance repairs a guy can make but all c5s will need it sooner or later

clutch kit, slave, master, couplers, inspect tube bearings, inspect rear main seal, replace rear end input and output seals {these are common leak spots with age}

if a shop does the labor you're around $2000 maybe a tad more, half of that parts, half labor

the ls7 clutch with a ram flywheel weighs the same as the OE ls6 and will perform much better while feeling identical and easy to drive in traffic

scoggin dickey has a good package deal on those

 

If I tackle anything TT related, I'll certainly knock out the clutch while I'm at it. I'll more than likely do the RST.

Today, while driving home, I got the car up to speed and got the vibrations to start. I then pushed the clutch in......and........ The vibration was still there, coasting, at speed, with the clutch in.

Does that cancel out drive-line related parts?

 

not at all, the driveline is still spinning when you have the clutch in.

 

I guess I should have said "clutch-related" parts, my apologies.

So, you guys are thinking it's leaning towards the drive-line and not a wheel bearing or tie-rod end?

 

no way to tell without testing

 

I'd say, almost for sure, it's driveline related. I've not yet had one of these drivelines apart but the type of vibration you are describing is exactly what a typical driveline with u-joints feels and sounds like when a u-joint is going bad.

 

agree, is my suspicion too

just hard to tell without testing. one way a guy could do this is to get the car in the air and and speed it up to where you start getting vibrations, look around and see if you can pinpoint the area it's coming from

be safe if you do this. a hard surface like a driveway or concrete with open grass in front of you is suggested,

 

Guess I'll need to get it on the lift and start doing some diagnostics.

See, that's what I thought too. That's what lead me to the TT Couplers, But, when I go around a bend that's curving towards the right, the vibrations tend to go away. And I feel most of the vibrations in my steering wheel and peddles. Somestimes I can hear a pulsing vibration that amplifies through the rear of the car.

Awesome, thank you for the information. I'll just have to start diagnosing. Hopefully it's nothing too serious!

 

You should check into the forum vendor who is having a clutch sale he installs clutches at a very reasonable price.