Unbalanced Tires
 

Installed a set of Pirelli's on the wife's Lexus in October. Ran great and really liked how they felt. In December brought it in for balance and rotation. In mid January began to notice a slight vibration. Progressively got worse. Brought car back in for balance and rotation. Was even worse after I got it back, especially on acceleration. It first showed up on acceleration but now happens at any speed from either a stop or while running down the road. So in the last week the only thing consistent is the inconsistency with the tries bouncing. I can have the cruise on at 65 and the vibration comes and goes while traveling at the same speed. Have an appt on Tuesday morning to have these looked at again. Is it possible that there is something internal to the tire that causes the inconsistency?

Usually with a balance problem you can "drive through" it. Little or no vibration until, say, 30 mph, then it gets better. Then at 45 or 60 you notice it to be greater again. That is due to to the harmonics. It could be, balance, radial (localized high spot) or lateral (side to side wobble) .due to uneven wear. Balancing won't correct a radial or lateral problem.

From your description I would lean to a wheel bearing or u joint on a rear wheel drive. But that is just a wild azz guess.

Can you feel the vibration in the steering wheel or in the seat of your pants.

Are you sure its the tire? Sounds like you could have a strut going bad. Ball joint?

Any cupping or uneven wear on the tires?

Check to see if one of your rims is bent. Especially if you have alloy rims and rough road surfaces, you’re at great risk to get bent rims. It happens to me all the time and that’s exactly how this behaves when I get a bent rim. They can be straightened but you have to ask around. Tire stores and the dealership will try to sell you new wheels and not straighten your old ones. If you do have to replace your wheels go with an aftermarket set from tirerack.com that is more robust and doesn’t get bent. Don’t ask me how I know this.

You can feel it in the seat not the steering wheel. No uneven wear at all. Its just so inconsistent.

A vibration mostly on acceleration, makes me think something in the driveline. Axle shaft, support bearing, rear prop shaft u joints tight?

Consistently getting worse seems to point to mechancal. Ball joint is also a possibility. A bent wheel would happen all at once. That could cause cupping or uneven wear after a number of miles and cause it to get worse.

I agree, Fred.

The "bouncing" of the tire happens at all situations, not just acceleration, but that is where the bouncing started. Tomorrow I'll get it in the air and see of there is any play in the front wheels. Thats where the vibration is coming from.

This is a 2013 Lexus es 350, fwd

If you can't seem to find the problem swap feont and rear tires. If it disappears, gets better or moves to the rear it will most likely be wheel /tire. It it stays up front it will probanly be wheel bearing or other as mentioned.

You went back 2 months after buying new tires
to rebalance your tires?

A tire could be self destructing. Belts separate, treads separate ... but from your description I would think something in the drive train.

Doesn't sound like a balance problem to me. As previously stated, maybe bad tire or something not tire at all like strut or wear in suspension. But, it's hard to diagnose this sort of thing remotely. What one person feels may be different from what the next person feels.

Check the balance, check for lateral and radial run out and then check the road force variation. Most likely you’ll find the problem in one of those three areas.

My 2cent armchair answer would be ordinarily "any of the above"- I've had every single thing mentioned happen to me over the years. Infact- I just went through a similar situation myself, which was solved by a lower ball joint.

Today, however, I feel sassy and am going to go against the grain. It's a defective tire- cord separating.

Final answer.

A lot of times a ball joint will give you clunking/ popping.
The cord separating explains why it is getting worse.
The second time you took it to get it balanced, meese guesses... they put the tires on a different balancing machine, and it didn't work as well as the first balancing machine (or a new weight immediately fell off). That's why it immediately felt worse. Also bonus points if the offending tire was on the rear and then rotated to the front of a fwd car. As you drove it more, the cords are worsening, so when you are driving at a constant speed with vibrations coming on and off, the unbalanced portion of the tires are phasing through harmonics as the unbalanced tires spins in unison/ out of unison with themselves, causing the feeling to subside/ or worsen depending on how the tires are rolling in relation to one another.

This could be compounded with a bent rim- rim gets hit. bent, damaging tire in process. now bent rim+ separating cords. The lower the profile tire/rim, the higher the chance.


I'm probably totally wrong, but I'm betting the bank on this! :D This stuff can be so frustrating.

Second guess- dead squirrel wrapped around driveline.

Good luck.

Slight possibility, but it happened to me once.

Check for fluid in the tire.

Seems the place I had mount them originally were not very diligent about draining their air compressor.

Same randomness you are describing.

Had the tire unmounted and found about 2ish cups of water in the tire.

Easy way to check would be have them balance the tire, wait one minute, check the balance of the tire again.

Long shot, but

Spin the tires while off the ground at highway speeds. If no on-car balancer around, put the car in drive and spin the driven wheels, then swap. You will find your problem.

Does it change pitch or go away when you steer left or right at speed?

I just replaced a front wheel hub (bearing) on a 2008 Lexus. Common problem with these cars.