Well...I've got all my new Energy Suspension Poly bushings installed...(9-5154 16mm rear, 9-5163 28mm front and 9-8120 rear end link kit)...I did have to slightly adapt the rear end link kits to fit...just slightly shortened the spacer sleeve about an 1/8 of an inch. Everything is real tight and hugs the road. However, I've still got that darn vibration in the steering wheel and body. Over the last several months I've replaced: both upper links, new shocks, rear inner tie rod ends, new tension rod bushings, new rear transmission mount and new tires balanced and aligned.
It just won't go away. It seems to be there at all speeds but seems to be the worst at about 35mph...at about 70-80 it seems to lessen. Since installing the polys, it seems to be even worse. From what I've been told, I've narrowed the problem down to the front lower control arms/ball joints or maybe the drive shaft carrier bearing....Just don't know where to go from here. Any tips on what to check or parts that often wear out that would cause this? I've got the service book and have been brushing up on how to check the control arms and ball joints. Just thought I would ask for some inside tips before I go any further on this endless quest...
thanks, robert
Shakin' 92 Q???
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Just part of the annual $3,000 per year maintenance and repair budget any old luxosport requires: $500 [for all fluids/filters] plus around 16 cents per mile based on 15,000 miles per year. [after 120k or so].
The driveshafts seem to last around 120,000 miles [if installed correctly.....optimized for phase and periodically stress relieved at the ujoints] that's only [0.00625 cents per mile just a little more than a 4,000 mile oil change costs].
10 years is a long time for one to last.
Roughly the same cost for changing CV joints and axles on a V8 FWD Cadillac at the same mileage.
The newer ones seem to last longer [based on a 94-95 Q mileage] but the longest we have had a new one on any car is 100,000 miles so we'll have to wait a few more years to evaluate any improvement.
Before you replace one have the ujoints checked for notchiness and stress relieved but if the center bearing has play it just needs replacing.
The driveshafts seem to last around 120,000 miles [if installed correctly.....optimized for phase and periodically stress relieved at the ujoints] that's only [0.00625 cents per mile just a little more than a 4,000 mile oil change costs].
10 years is a long time for one to last.
Roughly the same cost for changing CV joints and axles on a V8 FWD Cadillac at the same mileage.
The newer ones seem to last longer [based on a 94-95 Q mileage] but the longest we have had a new one on any car is 100,000 miles so we'll have to wait a few more years to evaluate any improvement.
Before you replace one have the ujoints checked for notchiness and stress relieved but if the center bearing has play it just needs replacing.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
The drive shaft turns 3.538 times faster than the wheel so a tire shake at 70 mph would be the same as 19.78 x 2 or 40 mph for a drive shaft.
The Q body stiffness and suspension sets a resonance at about 13 Hz.
All vibrations can be related to the rpm of any rotating component all you have to do is measure the frequencies [spectrum] of the vibration. Unfortunately most vehicle vibrations are in the subsonic range below 20-30 HZ [human hearing] except for high rpm things driven directly from the engine.
If a tires takes [78.5" to rotate once] and has a single bump [bad spot] 807 rotations per mile divided by 60= 13.45 HZ [for the fundamental] and 26.9/40.35 Hz [for the 2nd and 3rd harmonic].
ALL TIRES HAVE AN OVERLAP WHERE THE BELTS ARE HEAT CURED TOGETHER, therefore all ties have an extra stiff spot.....this is where the radial force measurement comes in......the amount of extra upward movement as this spot makes and brakes contact with the road is measured in pounds.Every tire has some [Michelins may have 3-5 pounds] poorly constructed or defective tires may have 20-50 pounds!The suspension stiffness varies as does the body stiffness [reaction as delayed by the shocks and springs to the tires upward movement].
Manufacturers set a tolerance [for the tires they install on a new car] .....they are all checked and match mounted by machine robot.
Infiniti currently allows 15 pounds of radial force. [Roughly the same amount of vibration that a 10 gram weight [ERROR] would cause at 70 mph.......a radial force imbalance is [feels] worse at 50-60 mph than at 75 or 90 mph because the frequency goes up..........same as a 20 gram wrong weight at 50 mph.
http://customwheelsmarket.com/tirbal.ht ... ec...4.cfm
Infiniti and all lux manufacturers are having a hard time finding and maintaining tires that meet or keep this specification.
Personally I want a tire that starts out at 2-5 pounds because they just get worse with miles as the internal cords snap and the overlap point gets worse and worse.On a Q a 10 gram error can be felt so the time between an absolute perfect balance 1 gram and 10 grams per side error is the time between rebalancing.Some tires last a day, some a week, some a month, and 1 or 2 last 2 months........Correct Michelins [H, V, Z rated] can still be in balance below 10 grams at 3 months if not abused [curbs- road hazards]...............just a function of build quality and strength of materials used.
Look at the error with the previous balance weights still on, you will learn YOUR tolerance for vibration.
The Q body stiffness and suspension sets a resonance at about 13 Hz.
All vibrations can be related to the rpm of any rotating component all you have to do is measure the frequencies [spectrum] of the vibration. Unfortunately most vehicle vibrations are in the subsonic range below 20-30 HZ [human hearing] except for high rpm things driven directly from the engine.
If a tires takes [78.5" to rotate once] and has a single bump [bad spot] 807 rotations per mile divided by 60= 13.45 HZ [for the fundamental] and 26.9/40.35 Hz [for the 2nd and 3rd harmonic].
ALL TIRES HAVE AN OVERLAP WHERE THE BELTS ARE HEAT CURED TOGETHER, therefore all ties have an extra stiff spot.....this is where the radial force measurement comes in......the amount of extra upward movement as this spot makes and brakes contact with the road is measured in pounds.Every tire has some [Michelins may have 3-5 pounds] poorly constructed or defective tires may have 20-50 pounds!The suspension stiffness varies as does the body stiffness [reaction as delayed by the shocks and springs to the tires upward movement].
Manufacturers set a tolerance [for the tires they install on a new car] .....they are all checked and match mounted by machine robot.
Infiniti currently allows 15 pounds of radial force. [Roughly the same amount of vibration that a 10 gram weight [ERROR] would cause at 70 mph.......a radial force imbalance is [feels] worse at 50-60 mph than at 75 or 90 mph because the frequency goes up..........same as a 20 gram wrong weight at 50 mph.
http://customwheelsmarket.com/tirbal.ht ... ec...4.cfm
Infiniti and all lux manufacturers are having a hard time finding and maintaining tires that meet or keep this specification.
Personally I want a tire that starts out at 2-5 pounds because they just get worse with miles as the internal cords snap and the overlap point gets worse and worse.On a Q a 10 gram error can be felt so the time between an absolute perfect balance 1 gram and 10 grams per side error is the time between rebalancing.Some tires last a day, some a week, some a month, and 1 or 2 last 2 months........Correct Michelins [H, V, Z rated] can still be in balance below 10 grams at 3 months if not abused [curbs- road hazards]...............just a function of build quality and strength of materials used.
Look at the error with the previous balance weights still on, you will learn YOUR tolerance for vibration.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Even the Michelins destroy themselves internally but the question is at what miles are they uncorrectable [radial force imbalance] gets so bad that even with flipping and rematch mounting and even wheel replacement that you can't get down to 15 pounds.....some of the G35 and Q are destroying non Michelin tires [or the tires destroy themselves] at less than 10,000 miles!!!!!!!!!!!!!!!!!!
Sidewall stiffness variation is another problem similar to cord overlap!
17 and 18" tires are more prone to this problem because of less sidewall to absorb the impacts so the wheels/tire cord get more and become out of spec faster.
About 70% of our oem wheeled and 90% of our 15-16" non oem Q customers have serious tire and wheel problems and 100% of our 17" and above have problems --- don't even ask about 18".
Sidewall stiffness variation is another problem similar to cord overlap!
17 and 18" tires are more prone to this problem because of less sidewall to absorb the impacts so the wheels/tire cord get more and become out of spec faster.
About 70% of our oem wheeled and 90% of our 15-16" non oem Q customers have serious tire and wheel problems and 100% of our 17" and above have problems --- don't even ask about 18".
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
http://www.discounttiredirect.com/roadForce.html
http://www.aiag.org/projects/project_li ... tmlgetting to be such a problem that bar code standards might be in place in 5-10 years.
GM is having such a problem that they are dropping from 15 pounds to 9 pound spec on some lux cars.............the Hunter 9700 has an accuracy of 2 pounds max to min force deviation and 0.5 gram weight selection!
"Ironically, developing it has put Hunter Engineering in the midst of a controversy with at least two major tire makers, as well as companies marketing competitive wheel balancers who claim their machines accomplish the same result without the ability to measure force variation.
At first, the GSP 9700 seemed to be welcomed by tire and auto makers alike. Goodyear, for one, purchased a quantity of the machines for its company-owned stores. But the tide of opinion changed dramatically after users of the machine began rejecting and returning non-uniform tires to suppliers for adjustment.
Goodyear and Michelin North America Inc. since have stipulated that data generated by the GSP 9700 will not be accepted as the basis for tire warranty claims.
Michelin said: "This type of machine" (the GSP 9700 was not mentioned by name) does not have the capability to accurately measure and determine tire uniformity, but does have the capability to optimize ride performance in the tire mounting process by properly measuring the tire-wheel as an assembly and offering a match-mounting preference."
For his part, Mr. Scribner said that while he takes issue with Michelin´s statement regarding the GSP 9700´s alleged inability to accurately measure tire uniformity, he doesn´t blame Goodyear and Michelin for taking such a stand.
"I can prove the machine does correlate (with tire industry standards for uniformity) very, very well when it´s used properly," he said. "But in the wrong hands it can be a nightmare. I wouldn´t want to open the flood gates for every tire shop that sends stuff back just because they bought a machine.
"We´ve created a piece of equipment that is revolutionizing the industry. But as a result of unintended consequences of people using the machines improperly, it´s creating a lot of questions along with the answers it´s (providing)."
Revolutionary or not, the machine is only as good as the person operating it, he said. "You have to have someone who´s willing and able to be trained to use the machine properly and who understands the big picture. We don´t want people using the machine as a screening device."
A happy guy who solved his problem after the dealer tired 17 tires to fix a bad wheel problem:"The initial checks showed that I had two wheel/tire assemblies that had real high road force variations. One was over 80 pounds and one was 60 pounds. The tire with the 80 pound reading was found to be defective and had to be replaced. After the work up all the tires now range from between 25 and 35 pound of force variations. This greatly improved the ride of the truck to a point it was acceptable. It is not perfect. The interesting thing was the operator told me that I would still be able to feel a slight vibration in the truck as anything over the 15-20 pound range can be felt. He told me this before the tires where remounted on the truck. He was right.
The only way to make it perfect is to put better tires on the truck. It came stock with Goodyear Wranglers and I hate them. I cannot wait for them to wear out so I can replace them with the Michelin LTX. He said that the LTX is consistently the best truck tire they have seen with the normal force variations at a consistent glass smooth 6 pounds.
The Michelin tires on my Maxima finally wore out after over 80,000 miles of use and had them replaced with, of course new Michelins. On the way home from the tire store I noticed a vibration in the car that has never been there. I took it back to the tire shop and had them rebalanced. Not much of a change.
I then took it to my friends shop and had them balanced on his GSP-9700 and the car was back to glass smooth. "from http://www.gadgetonline.com/vibration.htm
http://www.aiag.org/projects/project_li ... tmlgetting to be such a problem that bar code standards might be in place in 5-10 years.
GM is having such a problem that they are dropping from 15 pounds to 9 pound spec on some lux cars.............the Hunter 9700 has an accuracy of 2 pounds max to min force deviation and 0.5 gram weight selection!
"Ironically, developing it has put Hunter Engineering in the midst of a controversy with at least two major tire makers, as well as companies marketing competitive wheel balancers who claim their machines accomplish the same result without the ability to measure force variation.
At first, the GSP 9700 seemed to be welcomed by tire and auto makers alike. Goodyear, for one, purchased a quantity of the machines for its company-owned stores. But the tide of opinion changed dramatically after users of the machine began rejecting and returning non-uniform tires to suppliers for adjustment.
Goodyear and Michelin North America Inc. since have stipulated that data generated by the GSP 9700 will not be accepted as the basis for tire warranty claims.
Michelin said: "This type of machine" (the GSP 9700 was not mentioned by name) does not have the capability to accurately measure and determine tire uniformity, but does have the capability to optimize ride performance in the tire mounting process by properly measuring the tire-wheel as an assembly and offering a match-mounting preference."
For his part, Mr. Scribner said that while he takes issue with Michelin´s statement regarding the GSP 9700´s alleged inability to accurately measure tire uniformity, he doesn´t blame Goodyear and Michelin for taking such a stand.
"I can prove the machine does correlate (with tire industry standards for uniformity) very, very well when it´s used properly," he said. "But in the wrong hands it can be a nightmare. I wouldn´t want to open the flood gates for every tire shop that sends stuff back just because they bought a machine.
"We´ve created a piece of equipment that is revolutionizing the industry. But as a result of unintended consequences of people using the machines improperly, it´s creating a lot of questions along with the answers it´s (providing)."
Revolutionary or not, the machine is only as good as the person operating it, he said. "You have to have someone who´s willing and able to be trained to use the machine properly and who understands the big picture. We don´t want people using the machine as a screening device."
A happy guy who solved his problem after the dealer tired 17 tires to fix a bad wheel problem:"The initial checks showed that I had two wheel/tire assemblies that had real high road force variations. One was over 80 pounds and one was 60 pounds. The tire with the 80 pound reading was found to be defective and had to be replaced. After the work up all the tires now range from between 25 and 35 pound of force variations. This greatly improved the ride of the truck to a point it was acceptable. It is not perfect. The interesting thing was the operator told me that I would still be able to feel a slight vibration in the truck as anything over the 15-20 pound range can be felt. He told me this before the tires where remounted on the truck. He was right.
The only way to make it perfect is to put better tires on the truck. It came stock with Goodyear Wranglers and I hate them. I cannot wait for them to wear out so I can replace them with the Michelin LTX. He said that the LTX is consistently the best truck tire they have seen with the normal force variations at a consistent glass smooth 6 pounds.
The Michelin tires on my Maxima finally wore out after over 80,000 miles of use and had them replaced with, of course new Michelins. On the way home from the tire store I noticed a vibration in the car that has never been there. I took it back to the tire shop and had them rebalanced. Not much of a change.
I then took it to my friends shop and had them balanced on his GSP-9700 and the car was back to glass smooth. "from http://www.gadgetonline.com/vibration.htm
Just a thought but what about a wheel bearing?
I had one on the front go and gave me a vibration similar to what is described. Went away when bearing replaced. I am starting to get the same vibration in the rear now and will have the bearing inspected. Previous owners must have hit some bad potholes over time
Just a suggestion but get the rear bearings inspected. Put up on rack and run. The mechanic should use a stethescope to listen for any noise.
I had one on the front go and gave me a vibration similar to what is described. Went away when bearing replaced. I am starting to get the same vibration in the rear now and will have the bearing inspected. Previous owners must have hit some bad potholes over time
Just a suggestion but get the rear bearings inspected. Put up on rack and run. The mechanic should use a stethescope to listen for any noise.
...well, I found another problem. I guess I should have replaced both rear inner tie rods when I replaced the right rear. I checked and double checked but they appeared to be fine a few months ago. Now the left rear inner is shot. It gives a bunch. I'm just curious if that may be the problem though because I can feel the vib in the steering wheel. As far as wheel bearings, that was my first thought. From my experience, you should be able to hear them screaming at you. Everything feels tight. Who knows. I'll throw this tie rod on, balance, and align and check it out once again.