Vibration from somewhere

by **06MidnightBlue** » Sun Jul 22, 2012 2:16 am

Alright guys, I'm really hoping someone could help me with this.

I'm driving down the road. The surface is completely smooth and free of bumps. All of a sudden, I feel a vibration coming on throughout the truck. It progressively gets worse. I put my foot on the brake and get a MASSIVE vibration in the pedal and steering wheel. I come to a complete stop and begin driving again, and it's gone.

This is happening ONLY when driving on the highway.

It has done it a few times in the past, even before lifting. It used to be few and far between, now it's becoming more frequent.

I have so far inspected:

Wheel bearings, control arm bushings, spring seats, shock bushings, tires have been road forced balanced, alignment triple checked, sway bar bushings and end links (I know they wouldn't cause it, thought it couldn't hurt.)

CAN ANYONE POINT IN IN THE RIGHT DIRECTION?!

by **fishsticks** » Sun Jul 22, 2012 3:14 am

Did you PRY (BIG prybar) on your control arm bushings to make sure they are in fact OK? A visual inspection is almost useless. Ask me how I know. You can also watch the bushings while someone else turns the wheel side to side.

Checked the inner tie rod ends?

Any play in the rack?

Warped rotors?

Ball joints? (again with a BIG prybar)

by **navigator** » Sun Jul 22, 2012 7:37 am

reminds me of what the jeep guys refer to as death wobble.
it was usually related to tire balance, alignment and worn front end parts(TRE,BJ etc) like Donny already listed.

by **06MidnightBlue** » Sun Jul 22, 2012 10:29 am

I load tested the ball joints. No play at all

by **DirtyBacon04** » Sun Jul 22, 2012 3:55 pm

Mine does it on occasion, but i know it's my xmsn slipping in gear. Doubt thats what you got goin on.

by **The Roadie** » Mon Jul 23, 2012 11:04 am

Shocks all functioning? Do the corner push and look for a damped rebound.

by **06MidnightBlue** » Mon Jul 23, 2012 3:29 pm

Tested the shocks this morning. Everything is looking good

by **DirtyBacon04** » Mon Jul 23, 2012 6:30 pm

What is the frequency of the vibration? Like same speed of tires? Fluctuate with RPM? Does it happen on an incline/decline/don't matter? What speed does it start? How long at that speed before it starts? Xmsn temp? Check your fluids. Brake pedal abnormally squishy/firm at times?

YouTube Videos · by **Trail X** » Mon Jul 23, 2012 7:38 pm

I'm in agreement with Donny. The LCA bushings are about the only item that could have some non-obvious wear that would contribute to a death wobble like you have explained. Tie rods or a lower ball joint could potentially also do that - but they are also hard connections, so the play should be more obvious.

by **06MidnightBlue** » Mon Jul 23, 2012 8:15 pm

DirtyBacon04 wrote:What is the frequency of the vibration? Like same speed of tires? Fluctuate with RPM? Does it happen on an incline/decline/don't matter? What speed does it start? How long at that speed before it starts? Xmsn temp? Check your fluids. Brake pedal abnormally squishy/firm at times?

I'll be cruising at highway speeds for a wee bit before it starts. Incline and decline don't matter. It only happens at highway speeds. All the transmission fluids and filter have been changed and are full

by **06MidnightBlue** » Mon Jul 30, 2012 11:00 pm

Could this be it? Noticed it coming from the RR wheel sensor.

YouTube Videos · by **Trail X** » Tue Jul 31, 2012 12:40 pm

Are you referring to the slight leak? I highly doubt that a vibration felt in your steering wheel comes from a leaky rear wheel speed sensor.

by **06MidnightBlue** » Tue Jul 31, 2012 1:35 pm

I didn't know if it was somehow affecting the ABS system in anyway

by **06MidnightBlue** » Mon Aug 06, 2012 10:54 pm

Ok so something got me thinking today.

We got a notice today at work that the Mazda 3 has a faulty engine mount causing periodic body vibration.

Doesn't seem too unlikely that this could be my issue, does it?

by **navigator** » Tue Aug 07, 2012 9:16 am

do you have a vibration at idle when parked?

by **bartonmd** » Tue Aug 07, 2012 9:22 am

Due to privacy laws, we refer to it as "a dildo" not "your dildo"

by **06MidnightBlue** » Tue Aug 07, 2012 11:51 am

That's a negative Navigator.

Mike: ????

by **bartonmd** » Tue Aug 07, 2012 11:54 am

06MidnightBlue wrote:That's a negative Navigator.

Mike: ????

From Fight Club, in the airport, when security finds a vibrating dildo in his luggage.

Mike

by **06MidnightBlue** » Tue Aug 07, 2012 12:15 pm

Oh yea. Lol

YouTube Videos · by **Trail X** » Tue Aug 07, 2012 12:51 pm

How often does this occur? Is it something where, if you made a change like pulling an ABS fuse, you could tell if it made a difference after a few days? Or is it so sporadic that it would be difficult to tell if it fixed it?

If you could pull the ABS fuse, and it occurs again, at least you could rule out the ABS system as the cause. Now that I mention it though, normally ABS activation creates a palpable petal response where you can feel the ABS pulsing the petal. Do you feel this characteristic sensation when you have the vibrations? Plus... ABS can only activate when the driver presses the brake, right?

I am not familiar with the stability control on the later models. Can that pulse brakes without driver activation of the petal? If so, maybe that's the cause. Can you manually turn off the stability control? If so, try driving with it turned off and see if you have the vibrations again.

If you have the vibrations when stability control is turned off, and ABS is disabled... then I'd turn to replacing the LCAs next (to replace the lower ball joint and the LCA bushings at once).

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