Wheels Needed Balancing

[easysurfer]

Had to get the wheels balanced on my car today. It was making the steering wheel act like Chubby Checker doing "The Twist" (okay, I exaggerated a little) each time I exited a freeway. I did get a chance to ride my little bicyle (a folding type) back and forth to the car shop for a little exercise.

 

[frank]

what did they end up fixing? I was wondering because my car is doing the same thing between 50 and 60 while exiting the freeway. I didn't think it was balance, but didn't really know.

 

[Walt34]

It probably is nothing more than wheel balance, especially when it happens at specific speeds. That has to do with the vibrational harmonics of the suspension system combined with out of balance wheels.

 

[REWahoo]

It probably is nothing more than wheel balance, especially when it happens at specific speeds. That has to do with the vibrational harmonics of the suspension system combined with out of balance wheels.

Be sure to check for leaking flux capacitors as well - and worn Thai rods.

 

[easysurfer]

what did they end up fixing? I was wondering because my car is doing the same thing between 50 and 60 while exiting the freeway. I didn't think it was balance, but didn't really know.

They just did a wheel balance. Didn't cost a whole lot. Only $40.

I haven't had time to take it on the freeway yet but will in a couple of days.

Yeah, each time I'd brake while exiting a freeway or breaking from high speeds to slower, the steering wheel would start shaking.

A little info on the process of wheel balancing:

Wheel Balancing - Car-X

The irony of this is that though out of balance, the gas mileage I was getting seemed greater than normal

 

[travelover]

..........Yeah, each time I'd brake while exiting a freeway or breaking from high speeds to slower, the steering wheel would start shaking............

Your problem is not wheel balance, it is rotor thickness variation often miscalled rotor warpage. You will need to have the rotors replaced or remachined.

 

[ronocnikral]

Your problem is not wheel balance, it is rotor thickness variation often miscalled rotor warpage. You will need to have the rotors replaced or remachined.

+1. I was going to say the same thing before the OP even mentioned the problem was while braking. The hint was the problem was on exit ramps.

Passenger vehicle tires rarely ever need to be rebalanced as long as the weights don't fall off.

Autozone (or your favorite brand of car parts store) can sell you new rotors or help with turning them. Taking them off is not really a big chore (Assuming you have all the correct sockets and tools). Try not to touch the braking surface if you can help it.

 

[JakeBrake]

Very high mileage vehicles (say 200,000 miles) with disc brakes and sealed front wheel bearings will eventually need to have the hubs replaced. This is not inexpensive.

 

[easysurfer]

Your problem is not wheel balance, it is rotor thickness variation often miscalled rotor warpage. You will need to have the rotors replaced or remachined.

I read this, then looked Yahoo'ed (I use that more that Google) "Steering wheel shaking when braking" then said, it looks like you are completely right. Make sense to me. I probably have to to back to the car shop tomorrow and tell them to try again.

But my habits from w*rking with computers die hard. That is to run a test. So I ended up tonight taking the car on and off the freeway. Driving about 40 miles total, that did include braking while exiting the freeway. Much to my surprise...there wasn't a whole lot of Chubby Checker going on.

So now, I'm thinking, maybe I misread the symptoms? Or perhaps it did kind of need a wheel balance anyhow? Only when I purposely broke hard did I really notice many shaking. Regular blending in and out of freeway to exit, there was a big difference than before the wheel balancing.

So, for now I'll just leave drive the car as is unless the symptoms come back.

In a couple of days, I'll probably be driving about another 250 miles (mostly freeway) so that'll be another good test run.

 

[JOHNNIE36]

Your problem is not wheel balance, it is rotor thickness variation often miscalled rotor warpage. You will need to have the rotors replaced or remachined.

I would also think this to be your problem and not wheel balancing. If it was just balancing, I think you would notice it more often than on exit ramps and other times when braking.

 

[easysurfer]

I would also think this to be your problem and not wheel balancing. If it was just balancing, I think you would notice it more often than on exit ramps and other times when braking.

I actually agree as that makes more sense.

But as for the sypmtoms (or current lack of them), I'll just play it by ear. If it ain't broke, don't fix it.

If the chubby checker comes back, then I'll address that again when the twist re-appears.

 

[travelover]

I actually agree as that makes more sense.

But as for the sypmtoms (or current lack of them), I'll just play it by ear. If it ain't broke, don't fix it.

If the chubby checker comes back, then I'll address that again when the twist re-appears.

OK, I have a slight advantage, as this was my job for many years . Steering wheel nibble is caused when the tire rotational frequency (speed) of your tires (and brakes) lines up with the torsional resonant frequency of the steering wheel and column. Thus, it is usually worst at one speed - the resonant frequency. If that speed is say 60 mph and you are slowing from a higher expressway speed, you will go thorough it during deceleration, braking or not.

So, the issue can be either brake rotor variation or wheel imbalance induced. To test, slowly increase your speed and observe the steering wheel. Go around a few curves to reorient the front tires and try it again. If the steering wheel nibbles, it is tire balance or possibly tire flat spotting if the vehicle has been parked a long time.

Now brake a few times to sweep the speed where you have noticed the issue before. Brake at different rates. Ignore the people behind you giving you the finger. If the steering wheel nibbles during braking it is thickness variation or if you have had it parked a while, a rust spot on the disc. The rust spot will usually wear off.

 

[easysurfer]

OK, I have a slight advantage, as this was my job for many years . Steering wheel nibble is caused when the tire rotational frequency (speed) of your tires (and brakes) lines up with the torsional resonant frequency of the steering wheel and column. Thus, it is usually worst at one speed - the resonant frequency. If that speed is say 60 mph and you are slowing from a higher expressway speed, you will go thorough it during deceleration, braking or not.

So, the issue can be either brake rotor variation or wheel imbalance induced. To test, slowly increase your speed and observe the steering wheel. Go around a few curves to reorient the front tires and try it again. If the steering wheel nibbles, it is tire balance or possibly tire flat spotting if the vehicle has been parked a long time.

Now brake a few times to sweep the speed where you have noticed the issue before. Brake at different rates. Ignore the people behind you giving you the finger. If the steering wheel nibbles during braking it is thickness variation or if you have had it parked a while, a rust spot on the disc. The rust spot will usually wear off.

It's very interesting about how the different areas interact together. I haven't gone out and did all the testing, but the process is interesting.

I do know the nibbling that you mention, seems to only occur when I brake. Not while decelaration like taking my foot of the gas pedal.

Cool that that was you job for many years. I bet you could give us the inside scoop as to are most mechanics honest or not, and various tricks of the trade.

Thanks for your explanation.

 

[travelover]

...........
Cool that that was you job for many years. I bet you could give us the inside scoop as to are most mechanics honest or not, and various tricks of the trade.

Thanks for your explanation.

I was not a mechanic, I was a development engineer - you know the kind that actually drives the product instead of staring at a screen all day.

 

[easysurfer]

I was not a mechanic, I was a development engineer - you know the kind that actually drives the product instead of staring at a screen all day.

Sounds like you had a very interesting job. In may case, I much preferred staring at a screen all day, but got bummed when called to meet in a conference call

 

[kumquat]

If you are at all mechanically inclined and willing to do a bit of work, you can check the rotors with a dial indicator. I'm sure utube has many instructional videos, it's easy and the tool is not expensive.

If you determine it's rotors and decide to replace, I'd also install new pads (requardless of the wear on the existing ones). BTW, installing pads and rotors is not hard for a frugal person, my DD [-]can do it[/-] has done it (under spervision).

 

[Texas Proud]

Very high mileage vehicles (say 200,000 miles) with disc brakes and sealed front wheel bearings will eventually need to have the hubs replaced. This is not inexpensive.

Or a low mileage Ford Explorer..... just replaced my second one at 80K....

I HATE FORD....

 

[NW-Bound]

Coming to this thread late, but after reading the preceding technical discussions of various sources of car vibrations and wobble, described as "twisting", "shaking", "Chubby Checkering", "nibbling" etc..., I could not help adding a comment here. That is, there exists an invention that has proven very useful in industrial control and aerospace applications, and, in my view, could be readily applied to build a highly effective car suspension.

So, what is it? Instead of writing a rehashed description, I will defer to an excellent narration of this in the following video.


Rockwell Retro Encabulator - YouTube

So, some might say that this is really a means of propulsion, and ask what it has to do with suspension systems.

Ah a fair question, but the attentive watcher will notice that at 1:15 the presenter said that "...side fumbling was effectively prevented", and then again at 1:35, that "...it may also be employed in conjunction with the drawn reciprocation dingle arm, to reduce sinusoidal depleneration." Clearly, a simple modification will take advantage of the device anti-vibration property to make an active suspension of a very high suppression bandwidth.

OK, then, why is it that we have not seen this method in use at all? Not being an automotive engineer, actually not even an ME but an EE, I will defer to the automotive experts present in this forum, but of course have pondered this question myself.

The only potential drawbacks I could come up with are 1) the higher cost relative to the current century-old spring-based suspension, and 2) that the superior performance of the encabulating suspension may become a liability. Imagine a driver going down the highway with some loose or missing wheel lugs. He would be totally oblivious to the impending disaster, if his car had such an effective suspension, up to the point the loose wheel separated itself from the axle!

Still, with the proliferation of hybrid and electric vehicle, in the future can we expect to see cars with encabulating integrated suspension/propulsion systems? The advent of eletronics means that a car maker can let the active suspension system cancel out the road vibration for a smooth ride, while various onboard sensors will keep an eye on the deteriorating parts, in order to warn the driver of any hazardous situation that might develop.

PS. Having no skin in the game (I am not affiliated with any effort to design or manufacture any device using the discussed technology), I only brought this up for our enlightened members, in the remote chance that they were not already aware of it.

PPS. Laymen who are turned off by the technical discussion in the video will be well served by a Wikipedia article, which describes this important invention in plain English. You will find it here, which says that this was invented way back in 1944.

 

[Nords]

I was impressed with his sober mien and dignified bearing, right up until the writers made him use the word "dingle"...

But, hey, Anderson Cooper would've collapsed in giggles before the end of the first minute.

 

[JOHNNIE36]

I was impressed with his sober mien and dignified bearing, right up until the writers made him use the word "dingle"...

But, hey, Anderson Cooper would've collapsed in giggles before the end of the first minute.

Yeah, I wondered about the word "dingle" myself. But DW uses the word "dongle" all the time. I think a dongle is like a "stick" which holds data as in computer designs. That's what she's into and I hear these wierd terms come and go. So a "dingle" must be dang important. Sorry, I got off track.

 

[Nords]

But DW uses the word "dongle" all the time.

I'll bet it was months before she could say it without smirking!

Once upon a time one of our submarine fire control systems was giving us trouble from a piece of hardware that required a special implement with which to give it permission to launch. I can still hear a certain commanding officer saying "Weps, you should know better than to get your dongle stuck in a computer like that..." I had to transfer off the boat to get rid of that story.

 

[easysurfer]

Your problem is not wheel balance, it is rotor thickness variation often miscalled rotor warpage. You will need to have the rotors replaced or remachined.

Follow up... my car is back in the shop. Yes, the problem definitely was the brake rotors.

Both the front and rear brakes need work done. Calipers, brake pads, etc. etc. etc.

Oh well, now I know for next time when the twist happens ..must be the rotors.

 

[rescueme]

Follow up... my car is back in the shop. Yes, the problem definitely was the brake rotors.

Good to hear that you were not "unbalanced" ....