tnw

I've noticed the hood of my car vibrates significantly enough that I don't even want to take it past 80. I don't notice it until 65-70+. It actually causes the whole car to vibrate. It's extremely uncomfortable and makes me a little nervous. The vibration is so bad that I can sometimes hear the hood making a ticking noise as it taps the fender. Not good.

What can I check on that might need to be tightened up or replaced? Any other ideas on what to check on?

Side note, I also notice a whistling noise at highway speeds somewhere near my head as well. If anyone's noticed this and/or fixed it let me know.

MN_V

iTrader: (5)

Underbody air damn missing - results in high pressure in engine bay

Adjust the angle of your sunroof, torx screws - a few threads on this from the past with pics and specs.

tnw

Do you have a picture of the part I'm missing? I see some threads with part diagrams and have had a look under the front and can't spy what I'm missing.

BudRacing

iTrader: (3)

GM Part No.: 25752695

DEFLECTOR, Radiator Air




This is also on my parts-needed list. My hood issues aren't that severe though. Possibly because I'm also missing the molding at the top back-side of the hood.

vroom_vroom

iTrader: (5)

The copper crush washers for the break line fittings work like they where made for the hood hinge bolts on a semi related subject. Was driving me nuts and Home Depot stopped carrying the nylon ones in the old thread about them, found a bunch of the crush washers left over from a previous Brembo project and they worked like they where meant for it. No more rattle and last longer than plastic.

tnw

I couldn't find anything out of place under the bumper. I took a quick video, would you guys mind taking a look and confirming?

https://drive.google.com/open?id=0B0...HltMjJVODJqTFU

crazy tarzan

check that one of the rubber stops isn't missing - they are adjustable to, they screw in to lower, and out to raise.

should be on front radiator support in corners.

raven154

iTrader: (14)

You can see the back passengers side corner is hanging down a little. The clip is missing. That deflector starts to flaps at speed and makes the hood shake. It's pretty awesome seeing your hood bounce 2-3 inches when the whole deflector comes loose and starts flapping at 130 or so. I ended up using four self tapping screws and screwing it to the cradle. Even with the stock clips, if they are loose at all it can flap and make the hood bounce with it.

Choppy_Idle

Where is that long piece of rubber spoiler under the front, completely gone?

Regards
Ronald

tnw

I'll check this and see if I can button that down.

Unsure, I just got the car a few weeks ago! Looks like this is the part I'm missing: http://www.gmpartsdirect.com/cadilla...=air-deflector

Here's my actual car's front bumper:



Could that be part of the problem?

isis

iTrader: (1)

Definitely missing. I'm sure it could be an issue. I've never had mine off to confirm but makes sense.

tnw

Can any of you take a look at yours and see how many of the retainer clips I need to buy with it?

BudRacing

iTrader: (3)

You should be able to count the holes. I don't remember off-hand, but one of those boxes from the parts store had more than enough when I went through and replaced most of the broken ones.

raven154

iTrader: (14)

You can run the car without the rubber air dam and without the deflector on bottom. My car didn't have the rubber when I bought it either and I even drove hundreds of miles with the deflector missing while I figured out what I wanted to do with it to keep it from flopping around. It obviously looks better with the air dam in place but it's not contributing to the hood bounce. That's all the deflector flapping around.

Choppy_Idle

There were only 4 retainer clips ,to hold the rubber in place as i remember, they are cheap, buy some more, but there were 2 different in length and diameter, look with a caliper gauge before buying them is the best way, I assume!

Regards
Ronald

tnw

I got the radiator air deflector buttoned down (did not buy the chin spoiler/air deflector). It helped A BIT. I can now get up to 85+ but the vibration is still pretty bad.

Any more ideas?

vroom_vroom

iTrader: (5)

the chin deflector has a lot to do with it, as Chinese as it is it has a big impact. it the hood clicking rattling at all?

tnw

Not as much as before I got the radiator air deflector tied down but it does click a bit still.

vroom_vroom

iTrader: (5)

It's the hood hinges. They have the worlds thinnest copper washer on the shoulders. If you go to a parts store have them give you a copper crush washer for the brembo banjo bolts. Perfect fit no trimming and gets rid of the noise. It's like they where made for it.

Choppy_Idle

How does this works, change to a copper washer on the hood hinges, some pics available?

Regards
Ronald