shaking / vibration at 70-80mph

[AC439]

Ok...The front tires are new and were balanced and checked by two different Goodyear shops (a total of 4 times) and confirmed they are perfectly balanced and round. My car still has steering wheel vibrations and front end shaking starting at 70 and disappears at 80. It sort of feels like a typical out of balance tire/wheel.

So, the first suspect (front tires/wheels) is cleared. I'm thinking about what could be the next suspect? There must be an item that rotates - brake disc? half-shaft?

I don't remember how old are my brake discs but they were replaced long time ago due to pulsation braking. Probably close to 8-10 years ago. Drive shafts never give me problems, all boots are intact and no grinding or clicking sound while making turns. Also, the vibrations happens regardless of putting my right foot on the gas pedal or not. It will be there when the car is at that speed. When it vibrates, I lifted my foot completely off the gas pedal and I still feel the vibration until the car slows down below 70mph.

The suspension is old and likely worn but I think the vibration comes from a rotating part. Also, the outer steering ball joints are replaced not too long ago. The last mechanic did check on free play while he was checking the tires but didn't say anything afterwards. Anyone has any input? How to troubleshoot?

Thanks.- AC

[zigzag]

i have the same problem.... i think nothing of it at first but it gets kind of annoying since its only at that speed it happens.... anything under or over it rides as smooth as a bmw.

[russiankid]

Check you LCA bushing's. They could be cracked, but not sure if they could cause the vibration. Get your brakes done as well since you mentioned they are 8-10 years old.

[Demon1024]

I've been tracking a similar problem but mine at 65-75. new ball joints all around,new tires\rotors. i think it's the bushings on the lower control arm,or radius rods, but? I've also heard a bent rim can cause similar problems. luck to ya!

[russiankid]

I've been tracking a similar problem but mine at 65-75. new ball joints all around,new tires\rotors. i think it's the bushings on the lower control arm,or radius rods, but? I've also heard a bent rim can cause similar problems. luck to ya!

One of my rims is bent slightly, it is balanced and i don't have any vibrations.

[zigzag]

my dad tells me its the bushings.... and they do need to be replaced.... i should be doing them soon so i will let you know if thats the problem ive been having :)

[MessyHonda]

could be warped rotors

[zigzag]

could be warped rotors

nah we checked them out when we replaces my cv joints and my back break cylinders, they are still good.

[Oldblueaccord]

Besidess loose or worn suspension parts Its very possible that is the CV shafts. One of the joints has an oscallation in it. There not much you can do really for it besides replace and hope for the best.

You could try cleaning the CV shaft itself of any dirt or oil piled on it.Also make sure the inside of your rims are good and clean as well as the mounting faces.

Also if you can try an differant set of tires on the front. It is possible that its he tires even if they balance well. Most balance machines cant run a tire more than 30 mph off the car. There some new machines that can load a tire and balance it on the car.

Its just a thing with front wheel drive cars there more subseptable to vibrations then a rear drive live axle design.


wp

[AC439]

Thanks for the suggestions.

When the mechanic checked my front tires, I was there watching too. The tires and the wheels are definitely round. I didn't see any wobbling or anything and we checked more than once.

I don't have a pulsating brake pedal when braking. The rotor are probably 8-10 years old (I replaced them with Advance rotors) as far as I can remember. The brake pads are relatively new (less then 10k miles).

How do I check the bushing? If they are bad, I think I'd better replace the lower ball joints too (they are at least as old as I have the car - 14 years) and I know it's not easy to do (I read the forum). Are there any LCA kit that has everything in it (all bushings) or even a OEM LCA with bushings and ball joints?

More inputs? Thanks.

[Dr_Snooz]

Second the bushings. To check them, do a visual. If you see lots of cracking, or the rubber looks shot, that's probably your culprit. Also lift the car, grab all the suspension arms and jerk them around to see if you can get any slop. That will tell you a lot.
If everything checks out, do a Roadforce balance at your tire shop. It's something like $40/tire, but if it can diagnose a bad tire or rim, it's worth it. You aren't running really heavy rims or junk tires, right? Heavy rims will seriously stress out old suspension components that might already be getting tired.

[AC439]

Thanks. I'm running only original stock 13" aluminum rims.

I went to Ebay and didn't see much parts about LCA bushings. Do Autozone and Advance auto have them?

[russiankid]

I doubt you will find a kit. Just order some bushings, get the lower control arm off and have a shop press out the old ones and press new ones in. As far as the lower ball joint, you will need to remove the whole knuckle in order to do that.

[w261w261]

If you haven't swapped the tires front to rear, do that first. Sometimes a tire can be bad in a way that a tire shop can't tell.