Customer States Vehicle Vibrating at 100 MPH

[CarER]

Had a young customer come in this morning and said that his 2013 Mitsubishi Lancer Evolution has a vibration in the steering wheel under acceleration. He says, "When you accelerate there's a weird vibration in the steering wheel when you accelerate. It starts when you hit 60 and goes away at 80 then starts at 100 and disappears when it hits 120." He then proceeded to tell me that he replaced the tires, wheels balanced, alignment, etc...

 

I don't even know how to answer someone like that, I politely told him that I would look at the vehicle to see if there's anything obvious. But it's not like I'm going to go drive this thing at 100 to see what he's on about.

 

Well, that was my interesting story of the day.

[xrac]

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[alfredauto]

We had a guy in a while back who wanted me to test drive his jeep wrangler at high speeds in the rain because he said "it wobbled so bad I thought I was going to roll it" Sorry man I like my head attached to my body we'll check it on the lift. Lol.

[Gonzo]

I knew it, I knew it... I knew it. I didn't think I was the only one who ever had somebody wanting me to test drive a car at some outrageous speed.

 

But, I did have one guy who said he kept hitting his head on the roof when he would go over this bump real fast. I told him to wear his seat belt and perhaps slow down, or I could cut a whole in the roof and let his head stick through... choose an option.

[mspecperformance]

Just tell him you can't safely recreate the problem and it would be unlawful for you to try. Recommend him to find someone to roadforce balance his wheels and be done with him.

[carolinahigear]

Well....Guilty as charged, Your Honor!!

 

When I was 25 I bought a new Porsche. It was smooth driving all the way up to 150. After the tires got some wear on them a few months later, it started vibrated at about 110 & up. I went to a performance tire shop about 90 miles away and had them balanced, but still had a vibration on the way home. Now this was in 1980, before the internet, before I was in the tire business, so I looked in the back of Car and Driver Magazine for tire ads. I ordered a set of $800 (1980 price) Pirelli's and had them shipped to me. When they came in I drove to Atlanta and had them mounted and balanced. On the way home it drove smoothly up to 150, and I learned then that just because a tire is not worn out that it may not be balanceable to ride smoothly. This lesson has served me well through the years.

 

So nowadays when someone tells me they have a high speed vibration, and they've had them balanced already, I can steer them toward investing in some new rubber!

 

Hi-Gear

[stvstbsvc]

At my shop we always use the FINE setting and balance to .1 oz. instead of the normal .25 and that makes a HUGE difference. If the tires are within .1 oz. static AND dynamic (both sides) they should be smooth to just over 100 mph (I amateur car race in case you were wondering). Other than that I would agree with the above post!

As an aside - my best ever apprentice (dammit, he enlisted in the Coast Guard) was taking classes at the local community college. He was balancing his tires in class with a weight and side-cuts in his hand. The Instructor asked him what he was dong about the same time he looked at the read-out on the balancer. Scott (my apprentice) told him he was balancing tires as he had been taught and the instructor stuck around to see how to set the machine on FINE and how that all worked out! Never been prouder of one of my guys...

 

steve

[Spence]

At my shop we always use the FINE setting and balance to .1 oz. instead of the normal .25 and that makes a HUGE difference. If the tires are within .1 oz. static AND dynamic (both sides) they should be smooth to just over 100 mph (I amateur car race in case you were wondering). Other than that I would agree with the above post!

 

steve

 

You can balance to .1 oz and still have a bunch of vibration from road force variation. We do that and check the 1st. 2nd and 3rd harmonics on all tire/wheels we do as well as lateral force. I wasn't wondering but I also race. Drag and road racing.

 

Spence

[Martin]

Vibration under accelerastion could be worn inner cv joints.

[alfredauto]

I'm not disagreeing with the value of road force or fine balancing, but we've balanced literally tens of thousands of tires and you can't feel a 1/4oz or 10g imbalance. Even a half ounce on the back is not going to be noticeable on public roads.

 

Bent rims are the #1 cause of vibration. They balance out but they still don't go down the road smooth. #2 is garbage tires, the cheapo district of china makes square tires. (Not all Chinese tires are bad) They balance ok but will flatten out overnight. #3 is CV axles or stuck brake calipers. Get a rotor hot and it will warp, and if you have a stuck caliper it will shake with your foot off the brake. #4 is caked on mud, so obvious to most...

 

Incidentally loose tie rods and ball joints don't cause a vibration, they actually reduce it by absorbing it before it reaches the steering wheel. That's a Sinse-Ya moment when you rebuild a front end and now they feel their bent rim.

 

I took a class on NVH noise/vibration/harshness or something like that a while back, way back actually, and I recommend attending one of its offered. I went when I worked at Acura. You'd be surprised at what causes these "tire balance" issues. That's when ford was hanging large weights on the exhaust pipes.

Edited December 22, 2015 by alfredauto

[xrac]

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[CarER]

We looked over everything and we found an axle that was a tiny bit loose. We mentioned that to him and he took it to the dealer.

[b1qwkbird]

The quality of the tires is a huge factor. You can balance and balance a cheap set of tires and they still won't ride as well as a better set of tires. I have worked at numerous Goodyear stores and saw this time after time regardless of the balancer used. As Frank said, just because tires are new does not make them smooth.