Vibration at 70+

[jjhendri]

Hi got an 03 Vibe GT that I had to change 2 of the RSA's to 2 Eagle GT-HR plus 2 RSA'a (changed due to tire wear, only got 25K out of 2 RSA's), that when my vibration problem began in the steering wheel at speeds 70+. Took to dealer who checked alignment, balance and rotated tires to no avail. Can anyone on the forum help me on this

[ragingfish]

Every car I ever owned had a "sweet spot" or a speed range of about 3-4 mph where the car vibrated. In my bonneville, it was 73-78, my grand am was about 77-81, my sunfire 68-72. in the vibe, it's about 75-80. i've always assumed it was normal. if it's not, i don't know what the problem is.

[Reynoma]

I've had that same experience with my cars...there was always a speed at which vibrations would start/stop.For my Villager, it is around 65/67. For my old Dodge, it was from 10 through 70. I havn't experienced it in the Vibe, but I rarely go above 70 - I'm not interested in getting tickets.

[Hot Vibe]

It is time to take the tires back and get different ones. How bad is the vibration? Even if they have checked the balance/alignment/pressure the tires still may not be perfect. Get new tires before you put to many miles on them and they say no.

[jjhendri]

Thanks for all the replies, I was thinking about taking the 2 Eagle GT-HR back and just get the RSA's put back on so it would be back to OE. caused the vibration did not start until I change tires. I think they may have less than a 1K miles on them. Got it 9/17/03.

[ragingfish]

I have Goodyear Eagle RS/A tires, I still experience vibrations.Make sure your tire pressures are right as well: 32psi on all four tires.

[jjhendri]

Well let me give you an update on my vibration issue:Took the car back into dealer (10/21/03) and a tech rode with me to experience the vibration, said it was definitely the tires. Ok it was not the Eagele GT-HR tires but the RSA's that had the problem. They put the tires on a balancer that had road force. And this is the info from the receipt " Performed highspeed balance with road force. Found excessive road force variations in tires 21lbs unable to correct road force variations. Dismount tires and match with rim. Road force drop drop to only 20lbs. Performed high speed balance with road force on 4 tires. Right Front road force 20lbs, Left Front road force 17lbs. Right Rear road force 13lbs, Left Rear road force 9lbs. Move back tires to front and front to back. Back tires need replacing (RSA's). Eagle's are now on front. Can someone explain this in non-tech terms so I get it. I think I understand but need to see it in writing. I'm suppose to get the RSA's replaced but is 13lbs and 9lbs good?

[Geo]

If I remember correctly from Highschool Physics class...All matter has a certain frequency that can really get it vibrating. That's what happens when Glass shatters, when bass makes your body rumble, etc. There is no difference in cars, depending on the type of car, your tires and other stuff, there usually is a VERY specific range, as Raginfish said above, that the car will just get extremely loud with vibrations. It's just that the frequency of the road and tires matches in such a way that it hits this natural wave level with the car.In my Jeep Cherokee it was around 74mph, and I haven't payed attention to the Vibe much - the tires tend to silence road noise a bit, so that might have raised the speed at which my car vibrates a bit.Hopefully this helps, and like always, if can add/detract to this, please do. I like to know when I am right and wrong

[joatmon]

Looking at http://209.176.154.132/pub/technical/4127T/4127t.cfm (and also at http://www.craigautometrics.com/huntergsp9700.htm and http://www.broadwayautoclinic.com/Balancing.htm), it seems as if "road force" balancing means hooking it up to a special machine that loads the tire to simulate actual use, and measures a bunch of things that normal balancing won't find. The measurement that they quoted you appears to be a measurement of the amount of variation in tire stiffness when loaded. A low number is better. Apparently, by measuring the characteristics of the wheel and of the tire, it is sometimes possible to rotate the tire on the wheel to try to get the wheel eccentricities to cancel out the tire eccentricities, which is probably what they did by "Dismount tires and match with rim" Unfortunately, this only dropped the measurement a token amount, and that is why they are recommending that the tires be replaced. With the worse tires in the rear, you will probably not feel the vibration as much as when they were on the front.When you replaced the two RSAs with Eagles, did you replace the front tires and put the eagles in the back, moving the rear RSas to the front?I did not know that there was such a machine as the "Road Force" tire analyzer. Pretty cool technology.

[Sub-Vibe-R]

quote:If I remember correctly from Highschool Physics class...All matter has a certain frequency that can really get it vibrating. That's what happens when Glass shatters, when bass makes your body rumble, etc. There is no difference in cars, depending on the type of car, your tires and other stuff, there usually is a VERY specific range, as Raginfish said above, that the car will just get extremely loud with vibrations. It's just that the frequency of the road and tires matches in such a way that it hits this natural wave level with the car.This frequency is called "resonance frequency". We use this to set subwoofer boxes to get more power in a specific range of frequencies. It amplifie the wawe cause the "rebond" is totally synchronized with the other wave coming and the are added to each other.

[jjhendri]

Correct that the RSA's were moved from the back to the front. With the Eagle's on the rear. Yeah it's pretty cool techology but had a hard time understanding it the 1st time it was explained to me on how it worked. So I'm the process of waiting for replacement RSA's and hopefully this would correct the problem.Customer Assistance Center at Pontiac has been great, they have been following up with me every couple of days to insure that the problem was being worked on and asking to provide updates on my progress. Figure that it is better to have it documented so no one says that I never told them of the problem.

[redtrdmatrix]

You could always try a different brand of tires

[Stang2Vibe]

My cars had this "vibration range" as well. Maybe the older tires developed a flat spot somehow? Does your Vibe sit for long periods of time? The newer radial tires are supposed to be pretty good at preventing this, though.

[jjhendri]

No it never sits for long periods of time. Most would be 8 hours.

[Stang2Vibe]

Nah, that wouldn't do it. Are you still using the stock wheels? If you are, then the tire(s) was/were manufactured out of spec. They really should replace them since they can't be balanced to fix the problem. It's not something that is going to go away until the tires are replaced.

[threekrows]

I have the same thing in mine,just above 70.I have the dunlops,and have rotated them.I read about someone else having this problem on the GM tech forum too.

[jjhendri]

Still using OEM Rims. Suppose to get them replaced next week

[Stang2Vibe]

Well I hope they are able to do something to help correct this. Let us know how things turn out.

[philndz]

i too just got a vibration at 70 that continues to about 75mph.....it is very slight and doesnt bother me. it started when i rotated my tires the other day after missing one rotation so i think thats my problem.....just gotta wear them in a little to get even again.

[ragingfish]

There is no hard evidence to support the "myth" that faster travel means higher fatality rates. In fact, there are studies that show that increasing the speed limit on interstate and other limited-access roads would actually reduce fatality rates. (This is NOT promoting speeding on rural, country, and other roads where risk of injury to oneself, others, or animals is significantly greater!)Quote »The question, "Do speed limits matter?" hardly seems worthy of an answer. Insurance companies, police agencies, state transportation departments, and national safety organizations would have us believe that speed limits are a critical component of traffic regulation. Without those numbers on the signs and radar-wielding highway patrols, the entire system would self-destruct. This belief is based on several dubious precepts, none of which have ever been proven or justified.The most basic of these precepts is that motorists, in the absence of speed limits, will drive in a manner that ignores their own welfare and that of fellow highway users. That without speed limits, they would drive at reckless irresponsible speeds without concern for the consequences. Does that sound like you and the people you know?Another piece of speed limit folklore is that posted speed limits, given reasonable enforcement, can dictate traffic speeds. By extension, it is implied that raising or lowering posted speed limits will change the speed of traffic in that area. This notion has been thoroughly disproved on several occasions but the myth persists."Speed Kills" and "Slow is Safe" are well-entrenched slogans that have no basis in fact. Repeated long enough and loud enough, these slogans have taken on the aura of "truths."I know what you are thinking, "This guy is blowing smoke in my ear. He doesn't know what he's talking about." Stay with me for a bit longer and maybe I can change your mind, or at least bring about a little skepticism when one of those Public Service ads floats across your T.V. screen extolling the virtues of speed limits.Let's first look at the premise that drivers will go berserk if they are not confined by speed limits.Only one industrialized country officially allows unlimited speeds on portions of its public highways, Germany. Significant stretches of the Autobahn do not have speed limits. Yes, some vehicles travel at very high speeds, some in excess of 150 mph! But, the average speed for most vehicles is around 80 mph, about 10 mph faster than traffic in the U.S. on comparable highways. But, here's the clincher, the fatality rate on the German Autobahn is lower than the fatality rate on rural Interstates in the United States!Lest you think this is the product of Teutonic discipline and training, keep in mind that a large portion of the traffic on German highways originates in several other countries. Despite the cultural and language differences, there is a common understanding of a few basic rules: pass on the left, yield the left lane to faster traffic, and pay attention to your driving. It really works well.Do speed limits dictate travel speeds? Not much. Speed limits, backed up with intense enforcement, can retard traffic speeds, at least in the short term. However, the national 55 mph speed limit proved the folly of trying to use speed limits to slow traffic.Let's clear up one major misconception: Speed limits do not regulate traffic speeds; they never did and never will. Properly applied, speed limits should reflect the speed of the large (and safe) majority of vehicles using the highway. Keep in mind that millions upon millions of cars pound up and down our roads day in and day out, without having accidents. Except for a few vehicles, these cars are obviously traveling at speeds that are within reason. You say, "Aha, got you there. Those cars are going at reasonable speeds because they're being restrained by speed limits and the enforcement of those limits."Let me tell you about the most recent and most exhaustive federal study on this very subject.Over a period of five years, researchers monitored motorist response to speed limits at 227 different locations around the United States. First, motorist speeds were measured at all the locations. Next, the speed limits were raised on some roads and lowered on others while yet others remained the same. The results? Speeds did not change. People continued to drive at speeds that they felt were comfortable and safe, just like you and I do.This study also measured the relationship of speed limit changes and accident frequency. As you might expect, if speeds didn't change much, neither did accident rates. However, in those instances where speed limits were raised, there was a slight reduction in accidents. Could it be smoother traffic flow?Is slower really safer? Not on our rural highways it isn't. Again, federal and state studies have repeatedly shown that the folks most likely to get in an accident are the ones driving at speeds significantly below the average speed of traffic. In fact, the safest motorists, in terms of avoiding accidents, are those who are driving 5 mph to 10 mph above the average speed of traffic.You have probably seen those insurance company ads bemoaning the carnage and higher rates sure to follow, if speed limits are raised on rural highways. Do you know what percentage of all accidents occur on highways posted at 65 miles per hour? The answer is 2 percent. The insurance industry would have you believe that an increase of two miles per hour in traffic speeds (the increase that occurred when speed limits were increased from 55 mph to 65 mph on rural Interstates), will set highway safety back at least a millennium and end civilization as we know it.One of the most repeated and believed myths concerning speed limits goes like this, "You should keep the speed limit low because no matter where you set it, "they" (whoever "they" are) will always drive 10 miles over the limit." This is sheer nonsense, but it persists like the odor in a little kid's tennis shoes.In 1973, when we had a 75 mph speed limit on the rural Interstates in 10 different states, there was 90 percent or better compliance with the speed limit in those states. The states that had 70 mph limits had around 80 percent compliance and the states with 65 mph speed limits had approximately 60 to 70 percent compliance. In 1994, New York measured motorist compliance with its 55 mph speed limit on rural Interstates. The result: 4 percent of the motorists were obeying the speed limit. Do you see a pattern here?Whenever I'm confronted with the "they'll always drive 10 miles over" argument, I always ask, "If the speed limit was set at 100 mph would you then drive 110?"If you've moved in my direction at all you might ask, "Do speed limits have any value at all?" Yes they do, but only if they're established in the right way for the right reasons.The right reasons include informing the normally competent motorist about what is a safe and efficient speed for a given highway when there are good travel conditions. A second reason is to establish a speed limit that expedites smooth and harmonious traffic flow, in this instance a target that most vehicles should try to emulate.Multi-lane limited access highways can tolerate a great deal of speed variance, as long as there is good lane discipline. Two-lane highways, at the other extreme, function best with uniform vehicle speeds. Properly set speed limits can accommodate these different circumstances.Traffic engineers have repeatedly rediscovered that the best way to set speed limits is to measure the free-flowing speeds of traffic and determine the 85th percentile speed, which is the speed at which 85 percent of the vehicles are traveling at or below. With an 85th percentile speed limit, a 5 mph enforcement tolerance, and the unique phenomenn where faster traffic actually slows in the presence of reasonable speed limits, we will have 95 percent compliance with
the speed limit. Compare those numbers with New York's 4 percent compliance.Do speed limits matter? Yes they do. Today they generate millions of pointless traffic tickets and billions of dollars of undeserved insurance surcharges, disrupt traffic flow, increase congestion, and have created a siege mentality among those who frequently use our public highways.It doesn't have to be this way. We can have rational traffic regulation, including appropriate speed limits, that will expedite traffic, improve safety, and focus enforcement efforts toward those motorists who clearly drive in a reckless or discourteous manner. All we have to do is demand that it be done.

[NSimkins]

Time to get back on topic. Thanks.