# What's Causing My Car to Vibrate? **URL:** \ **Category:** Factual Questions\ **Created:** [May 4, 2007, 3:10am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708 "2007-05-04T03:10:02Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [May 4, 2007, 3:10am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/1 "2007-05-04T03:10:02Z")
Driving home yesterday the car (1981 Honda Prelude, 197K) had a definite waddle at 15 MPH or slower. Today, went I was at highway speeds it sounded like a helicopter was about to land on the roof of the car. I pulled over, checked the lugs and all of them were tight, none of the tires were flat, got back on the road and it still did it. Then there was a “Brrrump!” like I’d run over something in the road and everything pretty much cleared up, though I did have a bit of the waddle at low speeds. Nothing nearly so bad as it was yesterday, though. Any ideas? ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [May 4, 2007, 3:17am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/2 "2007-05-04T03:17:45Z")
I’ve seen a similar thing happen with a car that had CV joints that bolted onto the transmission, where the bolts were loose and caused a vibration like that until there was enough torque or speed, then the joint “locked” and it was quiet, until something would impact it or vibrate it hard enough and it would loosen up again. Eventually, the joint tore loose at speed…I’d check the CV joints. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [May 4, 2007, 3:20am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/3 "2007-05-04T03:20:36Z")
Hmm. Just had the CVs redone back in December (both sides). ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 4, 2007, 3:29am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/4 "2007-05-04T03:29:10Z")
My first guess would be a wheel bearing. Can you put it up on stands (making sure that it is secure) and see how much play is in the hubs? My second guess would be a CV joint. (I see on preview that **Una Persson** already threw that out and that you’ve had them replaced, but it’s certainly possible for them to have been improperly fitted or for the boot to have been torn by some debris and taken road damage.) Stranger ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [May 4, 2007, 3:45am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/5 "2007-05-04T03:45:06Z")
Well, jack up each wheel, and try wiggling the wheels and the joints. See what’s loose. This shouldn’t be that hard to find. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [May 4, 2007, 3:54am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/6 "2007-05-04T03:54:45Z")
[QUOTE=Tuckerfan] Then there was a “Brrrump!” like I’d run over something in the road and everything pretty much cleared up [/QUOTE] Might you have picked up some debris (perhaps on a wheel), and this was it (or most of it) falling off? ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [May 4, 2007, 4:17am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/7 "2007-05-04T04:17:26Z")
find an alley with a wall on one side. Drive at about 15-20 mph with the wall on your left. Roll down your window and listen. Reverse direction and roll down the right windows. If it is a wheel bearing, you will be able to hear which side. Maybe even front or back. (Or get somebody to stand by the side of the alley and listen as you drive by, they may be able to tell front or back. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 4, 2007, 4:59am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/8 "2007-05-04T04:59:50Z")
[QUOTE=Xema] Might you have picked up some debris (perhaps on a wheel), and this was it (or most of it) falling off? [/QUOTE] The continued waddle at low speeds suggests that there’s something else going on. When I was first reading the o.p. I was guessing a lost wheel weight, but the fact that it settled out after a while discounts that. I’ve had something simliar happen after driving through deep snow and having a mass of hard packed snow in the rim, but I’m assuming the o.p. isn’t driving in snow at this point. **Rick** ’s suggestion is a good idea, and may at least let you isolate which wheel it is. A loose bearing will sound, well, loose, like it’s rattling around. Do you get abnormal vibration when you use the brakes? Stranger ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [May 4, 2007, 7:28am UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/9 "2007-05-04T07:28:05Z")
No abnormal vibration when I hit the brakes. What’re the odds of it being the transmission causing this? ---
**Author:** ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)\ **Post date:** [May 4, 2007, 12:48pm UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/10 "2007-05-04T12:48:14Z")
You didn’t loose a break pad did you? ---
**Author:** ![A.R.Cane](https://avatars.discourse-cdn.com/v4/letter/a/ee7513/32.png) [@A.R.Cane](https://boards.straightdope.com/u/A.R.Cane)\ **Post date:** [May 4, 2007, 1:19pm UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/11 "2007-05-04T13:19:05Z")
Is this a rear wheel drive? Could be a U-joint going bad, or something wrapped around the driveshaft. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [May 4, 2007, 1:35pm UTC](https://boards.straightdope.com/t/whats-causing-my-car-to-vibrate/402708/12 "2007-05-04T13:35:42Z")
Up until it got better, it sounded to me like a textbook case of an out of round tire. I’d get all the wheels up in the air and check the tires carefully for any kind of debris sticking to one. Then spin each one and watch carefully for a flat spot or high spot. (Run it in gear to spin the drive wheels, get the free-spinning wheels going as fast as you can by hand. Looking from the side, get your eyeballs directly in line with the tread and watch for the “blip” in each revolution as the high or low spot comes around. Don’t be fooled by strictly visual differences, such as a damp spot on the tread.)