Vibration between 70-80 mph
Joined: Aug 2008
Posts: 43
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From: Austin Tx
Re: Vibration between 70-80 mph
Originally Posted by FTroopChief
Any possibility it's related to the SPOILER?
John P.
John P.
looks like in the underhood fuse panel fuse 20 is for the spoiler system. easy way to check would be to disable the spoiler, take it on a straight stretch and see if *** is still there... BTW... nice post on the tire marks BTW...
Seannon
Senior Member
Joined: Apr 2008
Posts: 1,426
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From: Heart of the Hills, Texas
Re: Vibration between 70-80 mph
Originally Posted by seannon
that is an interesting question... as i know that I get a rattle at about that speed... and i have noticed it goes away when the spoiler drops... as for vibration... not sure if that would be enough to be a culprit... I know there is a small amount of buffeting on the spoiler ( I need to adjust my hatch to stop it from rattling)
and there is a long list of other tire and wheel info, including the
looks like in the underhood fuse panel fuse 20 is for the spoiler system. easy way to check would be to disable the spoiler, take it on a straight stretch and see if *** is still there... BTW... nice post on the tire marks BTW...
seannon
and there is a long list of other tire and wheel info, including the
looks like in the underhood fuse panel fuse 20 is for the spoiler system. easy way to check would be to disable the spoiler, take it on a straight stretch and see if *** is still there... BTW... nice post on the tire marks BTW...
seannon
FROM TIRE RACK: http://www.tirerack.com/tires/tirete....jsp?techid=17
Scroll to the end of the Tire Match article I quoted, and there are a number of very informative articles on tires and wheels, including a calculator that will show actual speed vs speedometer reading should you decide to change tire sizes.
Also re the spoiler, check the owner's manual on raising and lowering it manually.
BTW-hope you can make it this Sunday. Looking forward to meeting you and Jenn.
John P.
Joined: Aug 2008
Posts: 43
Likes: 0
From: Austin Tx
Re: Vibration between 70-80 mph
Originally Posted by FTroopChief
Also re the spoiler, check the owner's manual on raising and lowering it manually.
BTW-hope you can make it this Sunday. Looking forward to meeting you and Jenn.
John P.
BTW-hope you can make it this Sunday. Looking forward to meeting you and Jenn.
John P.
as for the ride sunday, probably not going to make it... I have been working 12 hour days since Ike
Seannon
Forum Regular
Joined: Sep 2007
Posts: 963
Likes: 2
Re: Vibration between 70-80 mph
If the problem comes back after a time, you might be losing balance weights or you might have a problem with the wheel or suspension. Uneven wear can lead to a vibration and this is usually a sign of an alignment or suspension problem. This would also go away with a new tire and return later as was described.
In another life I worked in a wheel shop. We sold aftermarket wheels, tires, and rebuilt Dunlop, Dayton and Borrani wire wheels. I learned a lot there.
Vibration can be one of three major things:
- tires
- wheels
- suspension component(s)
If you don't know what you're doing you can chase a vibration for a long time.
Usually balancing is a good first choice - it gives you a chance to inspect wheel and tire, and visible suspension components, and to see any problems with the tire and wheel when it's on the balancing machine. If the tires balance and the problem goes away, there you go.
If the problem is still there after balancing, you probably missed a problem with the wheel or suspension. But don't ignore the possibility that the tire is improperly balanced. Give them another spin and see if they're still balanaced. I have watch many techs give the tire a quick spin, slap some weights on and immediately dismount the tire from the machine without verifying the balance is correct.
Take a look at the tire. Does it have something irregular about it - maybe a high spot (easier to see when the tire is spun) or an out-of-round issue?
Is the wheel straight (runs without wobbling from side to side) and concentric (doesn't have a high spot as it goes around). This is easier to see without the tire mounted.
And what about your suspension? Is there something loose, bent, broken or missing? Check ball joints, tie-rod ends, pitman arm, drag link, tie rod, hub, brake rotor (these can get warped and cause problems), bearings, steering box. With four-wheel independent suspension, don't forget the back.
Stick with one tech who can trace the problem from one end to the other. If several people look at it, each will start from a different point and possibly just repeat the last guy's checks with no new result.
In another life I worked in a wheel shop. We sold aftermarket wheels, tires, and rebuilt Dunlop, Dayton and Borrani wire wheels. I learned a lot there.
Vibration can be one of three major things:
- tires
- wheels
- suspension component(s)
If you don't know what you're doing you can chase a vibration for a long time.
Usually balancing is a good first choice - it gives you a chance to inspect wheel and tire, and visible suspension components, and to see any problems with the tire and wheel when it's on the balancing machine. If the tires balance and the problem goes away, there you go.
If the problem is still there after balancing, you probably missed a problem with the wheel or suspension. But don't ignore the possibility that the tire is improperly balanced. Give them another spin and see if they're still balanaced. I have watch many techs give the tire a quick spin, slap some weights on and immediately dismount the tire from the machine without verifying the balance is correct.
Take a look at the tire. Does it have something irregular about it - maybe a high spot (easier to see when the tire is spun) or an out-of-round issue?
Is the wheel straight (runs without wobbling from side to side) and concentric (doesn't have a high spot as it goes around). This is easier to see without the tire mounted.
And what about your suspension? Is there something loose, bent, broken or missing? Check ball joints, tie-rod ends, pitman arm, drag link, tie rod, hub, brake rotor (these can get warped and cause problems), bearings, steering box. With four-wheel independent suspension, don't forget the back.
Stick with one tech who can trace the problem from one end to the other. If several people look at it, each will start from a different point and possibly just repeat the last guy's checks with no new result.
Last edited by ppro; Sep 17, 2008 at 04:04 AM.
Senior Member
Joined: Jul 2008
Posts: 1,220
Likes: 0
From: KINGWOOD TEXAS!
Re: Vibration between 70-80 mph
Now I've noticed this same vibration with my new Conti's.
Like others, It's like a wave going through the car and cycles on/off every second or so. Very subtle but I really feel it on smooth hwy surfaces above 50=60 mph but under 130.
Discount has aligned them twice but it's going back for another.
Be aware of this potential issue when purchasing Conti's.
Like others, It's like a wave going through the car and cycles on/off every second or so. Very subtle but I really feel it on smooth hwy surfaces above 50=60 mph but under 130.
Discount has aligned them twice but it's going back for another.
Be aware of this potential issue when purchasing Conti's.
Senior Member
Joined: Jan 2007
Posts: 2,116
Likes: 0
From: Miami, Florida
Re: Vibration between 70-80 mph
Now I've noticed this same vibration with my new Conti's.
Like others, It's like a wave going through the car and cycles on/off every second or so. Very subtle but I really feel it on smooth hwy surfaces above 50=60 mph but under 130.
Discount has aligned them twice but it's going back for another.
Be aware of this potential issue when purchasing Conti's.
Like others, It's like a wave going through the car and cycles on/off every second or so. Very subtle but I really feel it on smooth hwy surfaces above 50=60 mph but under 130.
Discount has aligned them twice but it's going back for another.
Be aware of this potential issue when purchasing Conti's.
This was after changing the steering stablizer and the front steering bar. In my xase it was the rins.
Last edited by RMADERMAN; Oct 29, 2012 at 11:24 PM.
Joined: Sep 2011
Posts: 56
Likes: 0
From: Calgary
Re: Vibration between 70-80 mph
Any tire shop will be able to pick up on a wheel or tire error. If the wheel/tire is asking for to much weight. The tech will then road balance the tire, and the road balance will find any imperfections. Then allow you to correct them; with various methods; e.g.. Re-locate tire. I remember reading something about the steering linkage or stabilizer causing steering wheel vibrations. Can't remember the exact term but its cheap, and a common issue with crossfires. I will do more digging. Its not a wheel tire issue...
Joined: Sep 2011
Posts: 56
Likes: 0
From: Calgary
Re: Vibration between 70-80mph
I'm not making fun of anyone here, and not trying to be offensive, but if you are a "large" person and the alignment is done without you in the car, when you sit in the cockpit you can throw the alignment off.
May need to get aligned while sitting in the car. Offer it to the auto technicians so they don't have an awkward situation. Nothing worse then saying "Your car is messed up because you're too fat."
I am rather "portly" myself weighin in @ 255lbs. before anyone starts getting their panties in a bunch.
@ that weight in a 3000lb car is almost 10%
May need to get aligned while sitting in the car. Offer it to the auto technicians so they don't have an awkward situation. Nothing worse then saying "Your car is messed up because you're too fat."
I am rather "portly" myself weighin in @ 255lbs. before anyone starts getting their panties in a bunch.
@ that weight in a 3000lb car is almost 10%
Joined: Sep 2011
Posts: 56
Likes: 0
From: Calgary
Re: Vibration between 70-80 mph
Balancing is usually the culprit, however, have your tires been matched to your wheels? Before spin balancing especially with new tires and/or wheels, they should be matched to each other to assure any high or low spot or out of round is compensated for. A new tire generally has a yellow piece of tape indicating a reference spot and wheels should also have a mark. If the tires and wheels don't match, there is about a 3 to 4 inch window the tire can be moved on the wheel. Then balancing should be done. I prefer a hunter machine, but an old pro can do a PDG job on a static balancer.
FROM TIRE RACK: Tire Tech Information - Match Mounting to Enhance Tire & Wheel Uniformity
Tire and wheel manufacturers continually develop new manufacturing methods to enhance the uniformity of their products because radial runout, lateral runout, force variation and imbalance can affect a vehicle's ride quality.
Match mounting tires on wheels is a process where a tire's installed position on the wheel is specifically selected to help minimize the final combination's force variation and/or imbalance. One match mounting procedure aligns the tire's measured high point of radial force variation with the measured low point of the wheel's radial runout. The other simply aligns the tire's lightest spot with the wheel's heaviest spot.
Original Equipment (OE) tire suppliers are required to mark the tire's "high point" while OE wheel manufacturers mark the wheel's "low point." This helps the vehicle manufacturer match mount combinations that maximize new car ride quality while reducing the amount of balancing weight.
Today, many vehicle manufacturers specify the use of a temporary tag applied to tires and wheels that are removed before the vehicle is put into service. Unfortunately, this means that there are no permanent marks to reference later.
There was a time when the valve stem hole on standard wheels indicated the optimum place to which the tire should be match mounted. However, with the advent of styled, steel wheels and aluminum alloy wheels, the stem position evolved into an aesthetic issue rather than being a uniformity indicator. Add to this the probability of wheels retaining their original runout after thousands of miles of use and you can understand that simply mounting the tire so the colored dot is at the valve stem is no longer required practice.
We have found that the only way to accurately match mount replacement tires on used original or new aftermarket wheels is to use Hunter tire balancers which have the ability to measure wheel runout and tire force variations under load before the tire and wheel are installed on the vehicle. Using these machines, a colored dot might be positioned anywhere on the wheel relative to each wheel's runout measurement. In the end, the markers have little, if any, relevance when replacement tires are installed.
Hope this helps
Check your WINTER tire pressures too....
John P
FROM TIRE RACK: Tire Tech Information - Match Mounting to Enhance Tire & Wheel Uniformity
Tire and wheel manufacturers continually develop new manufacturing methods to enhance the uniformity of their products because radial runout, lateral runout, force variation and imbalance can affect a vehicle's ride quality.
Match mounting tires on wheels is a process where a tire's installed position on the wheel is specifically selected to help minimize the final combination's force variation and/or imbalance. One match mounting procedure aligns the tire's measured high point of radial force variation with the measured low point of the wheel's radial runout. The other simply aligns the tire's lightest spot with the wheel's heaviest spot.
Original Equipment (OE) tire suppliers are required to mark the tire's "high point" while OE wheel manufacturers mark the wheel's "low point." This helps the vehicle manufacturer match mount combinations that maximize new car ride quality while reducing the amount of balancing weight.
Today, many vehicle manufacturers specify the use of a temporary tag applied to tires and wheels that are removed before the vehicle is put into service. Unfortunately, this means that there are no permanent marks to reference later.There was a time when the valve stem hole on standard wheels indicated the optimum place to which the tire should be match mounted. However, with the advent of styled, steel wheels and aluminum alloy wheels, the stem position evolved into an aesthetic issue rather than being a uniformity indicator. Add to this the probability of wheels retaining their original runout after thousands of miles of use and you can understand that simply mounting the tire so the colored dot is at the valve stem is no longer required practice.
We have found that the only way to accurately match mount replacement tires on used original or new aftermarket wheels is to use Hunter tire balancers which have the ability to measure wheel runout and tire force variations under load before the tire and wheel are installed on the vehicle. Using these machines, a colored dot might be positioned anywhere on the wheel relative to each wheel's runout measurement. In the end, the markers have little, if any, relevance when replacement tires are installed.
Hope this helps
Check your WINTER tire pressures too....John P
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