Pop Quiz: What vibration is speed dependent, but not continuous - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Suspension, Brakes, Drivetrain discuss the wondrous effects of boost and your miata...

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 11-27-2013, 11:48 AM   #1
Ich verstehe nur Bahnhof
Thread Starter
iTrader: (3)
 
psyber_0ptix's Avatar
 
Join Date: Mar 2012
Location: Northern VA
Posts: 3,704
Total Cats: 319
Default Pop Quiz: What vibration is speed dependent, but not continuous

Hello all, I just wanted to farm out some analytic ideas to explain why I'm stranded at school before Thanksgiving.

On my commute into school, I noticed a periodic vibration that I feel through the floor that seemed to be wheel speed dependent. I'm already 20 miles into my 34 mile commute to school, mostly highway. As soon as I start to slow down to about 35mph, it becomes quite loud.

Pressing the brakes makes the sound disappear momentarily, but after about 15 seconds, it slowly creeps back up.

I barely feel it through the steering.

I have Corrado front rotors, and the brakes have been fine for months. I had the car inspected last week, no issues. I don't know if for whatever reason the hub ring that comes with the kit is missing (from doing inspection) and the rotor is no longer concentric with hub, but if thats the case, I have more serious issues to worry about.

It's raining fish and chowder up here in New England, and where I'm parked is quite constrained in space. Before I run out there in the downpour, shaking the wheel and scratching my head, has anyone had similar experiences? Unfortunately I don't have any tools or jack with me; which means I may be spending my Thanksgiving in my laboratory like a good grad student.

Last edited by psyber_0ptix; 11-27-2013 at 12:01 PM.
psyber_0ptix is online now   Reply With Quote
Old 11-27-2013, 01:25 PM   #2
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,009
Total Cats: 583
Default

Lugs tight? That would be the easiest.

You mention a noise. What does it sound like?
hornetball is online now   Reply With Quote
Old 11-27-2013, 01:55 PM   #3
Elite Member
 
Join Date: Jul 2007
Location: Little Rock, AR
Posts: 3,110
Total Cats: 127
Default

Front wheel bearings?
jacob300zx is offline   Reply With Quote
Old 11-27-2013, 02:41 PM   #4
Ich verstehe nur Bahnhof
Thread Starter
iTrader: (3)
 
psyber_0ptix's Avatar
 
Join Date: Mar 2012
Location: Northern VA
Posts: 3,704
Total Cats: 319
Default

The sound sound is hard to describe it sounds like a "whud whud whud" but no metal to metal clang bimps or pops. If it were the wheel bearing, that would be noticable continuously and not quiet down after braking for a short period. If the wheels were loose, it would definitely transmit through steering, right?

These are all good, I'll check when it lightens up out. I jist habe to see if anyone has a Jack I can use
psyber_0ptix is online now   Reply With Quote
Old 11-27-2013, 06:04 PM   #5
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,009
Total Cats: 583
Default

Wonder if you have a tire coming apart.
hornetball is online now   Reply With Quote
Old 11-27-2013, 08:02 PM   #6
Ich verstehe nur Bahnhof
Thread Starter
iTrader: (3)
 
psyber_0ptix's Avatar
 
Join Date: Mar 2012
Location: Northern VA
Posts: 3,704
Total Cats: 319
Default

Turns out you were correct about lug nuts. As I was going to take the wheels off to inspect the brakes and suspension, I found that both front wheels took no effort to break loose. Either someone came around last night and loosened them, or the were just snug tight after the inspector peeked at the brake pads.

Good call; I would have thought I'd feel it through the wheel though.

Thanks all for some quick trouble shooting. I'm glad it was something as mundane as lug nuts, and I was finally able to check when a friend brought a jack and some tools over.
psyber_0ptix is online now   Reply With Quote
Old 11-28-2013, 08:46 PM   #7
Junior Member
iTrader: (1)
 
Meeners's Avatar
 
Join Date: Jul 2008
Posts: 194
Total Cats: 0
Default

Consider yourself lucky... Speaking from experience... A few more feet and you would have seen your wheel bounce in front of you while your car surfs on it's lower sway bar end link and it's rotor.
Meeners is offline   Reply With Quote
Old 11-28-2013, 09:28 PM   #8
Newb
 
Join Date: Oct 2012
Posts: 31
Total Cats: -2
Default

bleezy is offline   Reply With Quote
Old 11-28-2013, 11:38 PM   #9
Ich verstehe nur Bahnhof
Thread Starter
iTrader: (3)
 
psyber_0ptix's Avatar
 
Join Date: Mar 2012
Location: Northern VA
Posts: 3,704
Total Cats: 319
Default

Dear lord....
psyber_0ptix is online now   Reply With Quote
Old 12-01-2013, 12:43 PM   #10
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,009
Total Cats: 583
Default

Be safe.

Torque wrench FTW.

At an HPDE over the summer, there was a McLaren that was throwing its lugs. They black flagged him before it turned into a 6-figure event -- lucky.
hornetball is online now   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM
3rd Time's a Charm...hopefully. zephyrusaurai Meet and Greet 2 09-28-2015 11:59 PM
WTB 90-97 miata low profile headlight kit DonPlatt WTB 0 09-25-2015 03:57 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 09:00 PM.