Intermittent vibration when braking

[crinkles]

When driving at 65, and light braking to 50, a terrible shake comes up through the steering wheel. problem is, it is intermittent.

I had the front brakes replaced, and rotors machined at toyota dealer. Because prior to that there was always a vauge shimmy through the wheel when braking.

After the work, everything feels fine 99% of the time, but on the highway, out of the blue, this would happen. at one stage i was really worried because the vibration became quite violent!

From reading the Haynes troubleshooting guide the only thing i can think of is the wheel bearings. the car only has 60,000 miles on it.

Maybe one disc is chattering and grabbing a pad so there is a differential effect from the driveshaft, making the steering shake, but that would mean a part of the new pad is welded to the disc, on at least one of the 4 sides of the two rotors.

if i brake mroe heavily the vibration generally goes away.
Love this car but I don't trust the front brakes/steering/suspension... any thoughts?

 

[JHZR2]

Poor turn job? Bad belt in a tire that causes an unbalance only at some speeds and force levels?

 

[nwjones18]

I'll be curious to see the responses to this one. I have the exact same problem, but on my old F-150. I have also changed the pads/rotors/calipers and it stops nice and smooth most of the time, but out of the blue it will shake terribly and sometimes pull hard to one side. I can't figure it out.

 

[Eddie]

I would check for a loose or worn suspension part.

 

[eljefino]

Originally Posted By: Eddie
I would check for a loose or worn suspension part.


+1 could be a lower ball joint or TRE. Would only shake if you aren't loading the bearings either turning in or out.

 

[J. A. Rizzo]

Turning the rotors won't correct warping, will it?

 

[rslifkin]

If they're truly warped, it's not a true fix. However, if they're just worn unevenly, it will fix them.

 

[Propflux01]

Cant help but wonder if the fluid is boiling. If it has ABS, perhaps its trying to compensate for that?

 

[crinkles]

No ABS. I ordered new rotors today. Although I don't see how it could be the rotors, unless they were very hot after a downhill (yeah yeah i DO downshift to engine brake...) and warp only then, and then back to normal when cooled down. Going tot ake the car to an independent to check over. If he can't fix it, well i just don't know.

 

[crinkles]

Originally Posted By: eljefino
Originally Posted By: Eddie
I would check for a loose or worn suspension part.


+1 could be a lower ball joint or TRE. Would only shake if you aren't loading the bearings either turning in or out.


what's a TRE? excuse my ignorance

 

[jds14]

crinkles...tie rod end. Could it be a sticky caliper? Had trouble with a caliper on my friends f150, we couldn't get rid of the shakes until one day the thing really did stick causing the rotor and pads to get really hot, ruining the pads. Replaced the caliper (and pads again) and all has been well.

 

[ChiTDI]

See if there is a set screw missing from one of the rotors. If lost or broken, it can provide you with a nice wobble on occasion. Brakes look good, calipers are lubed and not hanging up, and the rotors are true, right?

TRE - tie rod end

 

[Propflux01]

Originally Posted By: jds14
... Could it be a sticky caliper? Had trouble with a caliper on my friends f150, we couldn't get rid of the shakes until one day the thing really did stick causing the rotor and pads to get really hot, ruining the pads. Replaced the caliper (and pads again) and all has been well.


My Son's F100 Did exactly the same thing. And boy did it shake, and was that rotor ever HOT!!