LS Vibration

[rav]

My 2000 LS V8 is a great car with one notable annoyance- steering wheel vibration fin the 60-80 mph range. The vibration has been confirmed by general and service manager at the dealer and both have gone out of their way to try to diagnose the cause. It seems that since I brought it to their attention, they have noticed it on many of the LS's they have on the lot. So far the tires have been balanced twice by the dealer and most recently, the LS dealer located another car dealer in the area that has a Hunter 9700 tire balancing machine which I understand analyze's the tire/rim combination to identify the high and low spots in each diameter allowing the technician to match these characteristics to to ensure as "round" a tire as possible. After this, the tires are computer balanced at high speed. This machine also puts a "load" on the tire to simulate driving and road contact.
Unfortunately, after all of this, the dealer agrees with me that the vibration is somewhat more pronounced. The dealer has contacted LM technical support and they do not have a solution yet other than to say that it may be pronounced "road feel" that this car was engineered to provide. That is not a very good answer. BMW's have road feel without the vibration.
I am patiently waiting for enough complaints to get LM's attention so they put some engineering people to work on this problem. Until then, I will simply be annoyed driving what could be a world class american car.
By the way, several posts about this on Edmund's, some of which simply conclude that the Firestone Firehawks were a poor tire choice. If I was sure that was it and was aware of a suitable replacement, I would simply buy new tires.

Any suggestions would be appreciated.

By the way, the layout of functionality of this site is excellent.

[351CJ]

rav: I have a slight vibration in the 70 - 80 MPH range (Firestones). I don't feel it in the steering wheel, but I can feel and hear the vibration. I don't know how far back on Edmunds you looked (Parts I, II, III etc). But one poster said the problem was the tire belts can bunch up. If this is the case then the tire will look like it is balanced on the machine but you will feel the vibration on the road.

The majority concensus is that Michelins will completely fix the problem. Michelins are made in a segmented mold not a clamshell like the Firestones. One Endmumds poster said the Energy MXV4's solved all the vibration problems and added 2 MPG to his gas mileage.

I'm sure one of the main reasons why Ford uses the Firestones is price.

[Lscman]

Maybe I'm too critical but anyone that claims 2 MPG better by changing brands of tire in the same width and both modern radials is dreaming. Belt problems will not reduce mileage significantly either. Sounds like a fuel elixor additive commercial and brings into question his opinion on the vibration solution, IMHO. A set of squirming 1960 vintage 2 ply bias plies with 12 lbs pressure "might" reduce mileage by two MPG. Five passengers, a trunkload of stuff and a Cargo roof rack hauler might do that too. My mileage drops by two when I haul a loaded trailer. I am not saying a tire is not defective, but the Firestone SZ50 Firehawk's are a very popular, top handling tire with few complaints, at least in road racing. Michelin's may have slightly higher quality control, but they aren't a popular choice for race-like handling.

------------------
Rick, Road Track Terror in my '88 Mark VII LSC. See ya at Northeast Events! Pgh, PA

[This message has been edited by Lscman (edited March 29, 2000).]

[351CJ]

LSCMAN: A couple of comments:

1. Presently all LS V8's and V6 Sports Pkg come with Firestone Firehawk LH tires.

2. The Michelin MXV4's are supposed to be low rolling resistance tires.

3. I'm a bit scheptical of a 2 MPG radial to radial jump in milage. Could be warmer weather and his LS is more broken in contributing to the mileage gain.

4. When I replaced the OEM Goodyear wide oval bias ply tires on my 1972 Torino with Goodyear radials I saw a good 2 MPG jump. In addition it was if I bought a new car. Those old wide ovals were real dogs, unless you liked to spin the tires and hop over concrete expansion joints. They were real good at that.

[351CJ]

rav: The 60-80 MPH vibration in my LS appears to be getting worse as miles pile up on it. I don't believe it is in the tires but it could be tire vibration exciting some other resonance.

[351CJ]

rav: Any update on your vibrtion problem? I'm pursuing 2 possible reasons for the vibration: 1. suspension alignment 2. Drivetrain design issue.

Is you LS V8 Sport or non-Sport? When was it built?

[rav]

quote:Originally posted by 351CJ:
rav: Any update on your vibrtion problem? I'm pursuing 2 possible reasons for the vibration: 1. suspension alignment 2. Drivetrain design issue.

Is you LS V8 Sport or non-Sport? When was it built?

c51CJ- No update regarding repairs yet and at 8600 miles, does not appear to be getting worse. After the dealer's previous attempt to repair through the tird balancing it did seem worse and the service manager mentioned tha the was going to order some type of spring for the steering mechanism. I have been notified tha the part has arrived sothe car has not been back to the dealer since the last attempted repair. My LS- v-8 is a non sport built in October 1999. The dealer I purchased this car from was also the selling dealer for the car that appeared in Consumer Reports last fall. That car, a v-6, aloso had a vibration that was repaired by replcing the rear axles, which apparently were defective from the third party vendor. The dealer checked my car for a similar problem and concluded it was not the axles.

Can you fill me in on how you came to the pursuit of the two possiblities you mentioned?

[Avu3]

Hi All,

I'm not an LS owner, and haven't studied them TOO Much, so this may be way off, but...
These things are supposed to be similar to the Jag S-Type, correct?
If so, one course of troubleshooting would be to anylize if the Jags have the same problem.

If so, you know it is a component that appears on both platforms.

If not, you get a strong hint that it is a component (or assembly) that is unique or was modified for the LS.

Here's another thought. I don't know if the LS has an idependant rear (I assume it does) If so, I know that the 99 Mustang Cobra with the Independat rear was not well designed, and suffered from similar problems. No idea if there was a resolution.

Best of luck

[351CJ]

rav: Thanks for the update and info. on the
Consumer's LS rear axles. The suspension alighnment issue came from a dealer tech. I have not been able to find out any more info. or verify if the info. is correct or true. The other possibility is the rear axles. I've heard that there are new axles. Right now I have conflicting information whether it's a manufacturing problem or a design update. I'm guessing my problem is the rear axles. It takes 5 to 10 miles at speed before the vibration appears. It also feels as if it starts in the rear of the car. Sometimes the steering wheel will start to vibrate but not all the time. The vibration frequency does not change with speed which makes me conclude it is not the tires.

Avu3: I believe most of the suspension parts (A arms, differential)are the same as the S-Type. The main difference is the springs and shocks. I'm not sure if the hubs are the same or not. I've heard of some similar problems with the S-Type but I don't know if they are the same as the LS.

[351CJ]

Avu3: Interesting on the Mustang Cobra IRS. I've heard that Ford is holding off putting the IRS in the Mustang GT until 2001 MY because they want to see how the Cobra IRS works out. The LS does have IRS. I believe it is more like the Jag S-Type than the Cobra. The LS IRS has an interesting and effective anti-dive ability. Given the size and weight of the LS, it is amazing how level the LS stays during hard braking and cornering.

[Avu3]

Out of curiosity, does the LS have airbags? Do you know about the S-Type?

[rav]

quote:Originally posted by Avu3:
Out of curiosity, does the LS have airbags? Do you know about the S-Type?

AVu3- The LS does have airbags. I presume the S-Tyoe does also

[351CJ]

Avu3: your asked: "Out of curiosity, does the LS have airbags? Do you know about the S-Type?"

Do you mean air bag suspension? If so the answer is no, the LS and S-type use conventional steel coil springs.

If you mean crash airbags the answer is Yes, Driver & Front passenger front and side.

[Avu3]

Major brain failure, here; sorry. I was asking about air bag suspension, not air bags for crash defense (are they even an option anymore?)

I know very little about the S-Type, other than what I have read from the magazines and seen on TV.

I may be ignorant, but what mechanism would a conventional spring type car use for load leveling? Seems like if you filled the trunk, you could be draggin', which would be embarassing in a luxury car....

Begging your forgiveness for my brain fade...
Avu3

[351CJ]

Avu3: Can't say I'm a Jag expert either (Jaguars on Line anyone?). I do remember reading that the S-Type has some sort of active suspension. In particular I seem to remember seeing in some mag. that the shocks had 2 electronically controlled settings. I don't remember seeing anywhere that the Jag has auto. leveling or ride height.