Question - Steering vibration
Thread Starter
Member
Joined: May 2003
Posts: 118
Likes: 0
From: Maryland
Question - Steering vibration
I know I have some flat spots in my tires, and I have balanced, and re-balanced to no avail....But today I noticed something else with the steering....I was going about 55mph and took my hands off the wheel and noticed the Steering wheel vibrating, going up and down...the road was smooth and I had been driving for over 10min...I don't know if it's normal or not, but when I grip the wheel I feel more vibration through which I'm noticing more and more....am I a nut, or is something wrong?
Super Member
Joined: Jul 2002
Posts: 678
Likes: 1
From: Vancouver WA
'14 GLK250 Diesel
We've had this discussion - the tires develop flat spots, and they are going to shake. The phenomenon you describe fits this exactly, and I've had it happen often enough I know what you are describing.
You need to get a set of tires that are not Z-rated, preferably H-rated, preferably Michelins. Have them balanced on a road-force balancer by someone who is willing to take the time to see that no one tire generates more than 9 lbs of road-force when the job is done - less is better. Check all tire/wheel combos for both lateral and vertical runout - accept no more than 1.0 - 1.5 mm of runout in any direction.
In the meantime, the strategy goes like this:
-Temporarily inflate them to 45 psi
-Drive at freeway speeds for at least 30 minutes or 30 miles
-While they are still hot, get to a tire shop with a road-force measuring balancing machine [this can be the dealer, or an indie shop]. Arrange it in advance so you can get the car on a lift as soon as you roll in, with the tires still hot
-Rebalance the OEM tires on the road-force machine. If any one of them generates 10 lbs or more of road force, you can assume it will NEVER be round enough to stop shaking the car
-If all four can balance out at no more than 5lbs - 9lbs of road force, put them back on the car and torque the wheel bolts BY HAND to 80 ft-lbs
-Put the pressures back to the factory recommended figures.
I can guarantee you that if you get all 4 tires, either the originals or replacements, down to a road-force number of 5 to 8 lbs or less, you will be happy. But to do this with the OEM "sports" tires is very, very difficult. This is the price you pay for the C230's "sporty" tire/wheel combination.
Our "boring and slow" C240 has Conti CH 95s, 205/55x16 that will flat-spot more easily than the Michelin MXV4s that are my real favorite, but are still good for about 4-5 days of sitting without serious problems. Still, it has been my habit for the past 12 years to jack up all four wheels [with cheap Wal-Mart floor jacks and wooden pads to avoid damaging the jacking points] EVERY time the car comes in the garage at night. This process takes a grand total of two minutes when the car is put away, and less than that when we leave. Voila - no flat spots, ever. Everyone thinks I'm nuts - on the other hand, I'm here telling you I KNOW what you're going through, and it would drive me crazy in a day.
I developed the jacking routine as a defensive measure after we retired - it isn't unusual for the car to sit for 5-10 days between trips, depending on the time of year. We have most everything within walking distance [movies, dentist, restaurants, many stores], so the car currently averages about 7500 miles a year. I learned this lesson with an early 90's Toyota Cressida that was a great car, but one that was hyper-sensitive to this problem.
You need to get a set of tires that are not Z-rated, preferably H-rated, preferably Michelins. Have them balanced on a road-force balancer by someone who is willing to take the time to see that no one tire generates more than 9 lbs of road-force when the job is done - less is better. Check all tire/wheel combos for both lateral and vertical runout - accept no more than 1.0 - 1.5 mm of runout in any direction.
In the meantime, the strategy goes like this:
-Temporarily inflate them to 45 psi
-Drive at freeway speeds for at least 30 minutes or 30 miles
-While they are still hot, get to a tire shop with a road-force measuring balancing machine [this can be the dealer, or an indie shop]. Arrange it in advance so you can get the car on a lift as soon as you roll in, with the tires still hot
-Rebalance the OEM tires on the road-force machine. If any one of them generates 10 lbs or more of road force, you can assume it will NEVER be round enough to stop shaking the car
-If all four can balance out at no more than 5lbs - 9lbs of road force, put them back on the car and torque the wheel bolts BY HAND to 80 ft-lbs
-Put the pressures back to the factory recommended figures.
I can guarantee you that if you get all 4 tires, either the originals or replacements, down to a road-force number of 5 to 8 lbs or less, you will be happy. But to do this with the OEM "sports" tires is very, very difficult. This is the price you pay for the C230's "sporty" tire/wheel combination.
Our "boring and slow" C240 has Conti CH 95s, 205/55x16 that will flat-spot more easily than the Michelin MXV4s that are my real favorite, but are still good for about 4-5 days of sitting without serious problems. Still, it has been my habit for the past 12 years to jack up all four wheels [with cheap Wal-Mart floor jacks and wooden pads to avoid damaging the jacking points] EVERY time the car comes in the garage at night. This process takes a grand total of two minutes when the car is put away, and less than that when we leave. Voila - no flat spots, ever. Everyone thinks I'm nuts - on the other hand, I'm here telling you I KNOW what you're going through, and it would drive me crazy in a day.
I developed the jacking routine as a defensive measure after we retired - it isn't unusual for the car to sit for 5-10 days between trips, depending on the time of year. We have most everything within walking distance [movies, dentist, restaurants, many stores], so the car currently averages about 7500 miles a year. I learned this lesson with an early 90's Toyota Cressida that was a great car, but one that was hyper-sensitive to this problem.
Last edited by jrct9454; Apr 20, 2004 at 06:14 PM.
Senior Member
Joined: Mar 2003
Posts: 350
Likes: 0
From: Stamford, CT
2003 C230
Pete, get rid of the Contis.
Get some Toyo Proxes 4. I paid $105 for 18 inchers. I am sure the 17s are less than $100 each. Same size, spec. All vibrations will go away. Actually, my car is in for Service A right now and the loaner has contis. Also flat spots like crazy 
CZ
CZ
Senior Member
Joined: Mar 2003
Posts: 350
Likes: 0
From: Stamford, CT
2003 C230
John, all the Hunter 9700 guy said is that anything under 27lbs passes.
One of my Contis had 67lbs!!!!!!!!!!!!!!
That got replaced. All the contis were in the mid 10s.
Replaced them with Toyos. 3 of them were from 6-8. One came in at 21. Still, all vibration is gone.
CZ
That got replaced. All the contis were in the mid 10s.
Replaced them with Toyos. 3 of them were from 6-8. One came in at 21. Still, all vibration is gone.
CZ
Super Member
Joined: Jul 2002
Posts: 678
Likes: 1
From: Vancouver WA
'14 GLK250 Diesel
27 lbs of road force is NOT good enough for me.
I also know that any tire/wheel combo that is properly balanced and round enough to be acceptable on any MB should have a r-f of 10 lbs or less. If you can't get it that low, then the tire would shake the car enough for ME to notice. My guess is your one bad guy is out of round by 1.5 - 2.0 mm....not much by ordinary standards, but too much for me.
All 5 [I have an alloy spare and use it in our tire rotation] of our OEM Conti CH95s on our C240 have r-f figures of 4-8 lbs; four of those are the original mounts from the factory, the other was mounted and balanced by the dealer in Sacramento.
I would run very fast to another provider if the tech at the machine was going to be content with 27 lbs.
Even with used, take-off steel wheels, we had our '03 Corolla with Michelins where no one tire was more than 15lbs, and most were around 8-10...this was acceptable on the Corolla, but I could feel it when the least-round one was on the front. Guess I have a sensitive butt for these things...
I also know that any tire/wheel combo that is properly balanced and round enough to be acceptable on any MB should have a r-f of 10 lbs or less. If you can't get it that low, then the tire would shake the car enough for ME to notice. My guess is your one bad guy is out of round by 1.5 - 2.0 mm....not much by ordinary standards, but too much for me.
All 5 [I have an alloy spare and use it in our tire rotation] of our OEM Conti CH95s on our C240 have r-f figures of 4-8 lbs; four of those are the original mounts from the factory, the other was mounted and balanced by the dealer in Sacramento.
I would run very fast to another provider if the tech at the machine was going to be content with 27 lbs.
Even with used, take-off steel wheels, we had our '03 Corolla with Michelins where no one tire was more than 15lbs, and most were around 8-10...this was acceptable on the Corolla, but I could feel it when the least-round one was on the front. Guess I have a sensitive butt for these things...
Last edited by jrct9454; Apr 21, 2004 at 04:41 PM.
