99 Pont GA Shaking problems

I've done everything I can think of with no avail.
My car shakes only when I go over 80 miles.

Alignment
Balance: front and back
Rotation
Rack and Pinning (I'm sorry guys if I'm missing spelling it)
Tire Rods
New Tires
Alignment and Balance again.
Brakes and Rotors,
Balance again.
Alignment once more.
Rotation
I have an appointment to see the dealer, but before I go I wanted to know if there's anything else I'm missing..

Also when I take my foot of the pedal it makes a loud roaring sound (only started with the new brakes and rotors)

Welcome to AF !

When you say your cars shakes over 80miles, was that 80 mph or after driving the car 80 miles??

Could be your CV joints causing the vibrations. My SE had a 57-62 mph shake, changed everything it still done it, untill I changed both CV joints.

if you were refering to 80mph, then it most likly the tires, because most tires are NOT rated for 80mph, except Z-rated tires which are rated for around 100mph.

Getting them balanced properly is important too. And if you hav stock wheel, alot of times those wheel weights fall of easily.
Hope that helps !

Ok, thank you. I was referring to mph.
I have 18inch rims...I don't know if my tires are z-rated probably not.
I will get z rated tires and cv joints and update everyone..

Thanks again....

i have this same problem, my car did fine, but than i got new 18 in rims about a month ago, and right at 80 it starts shaking, i feel like im gonna crash, ive done everything and i have very good tires, i dont know what to do

I see lots of aftermarket rims on cars driving down the road with the wheels obviously out of balance, so it may be an issue with the rim itself. I would lean more heavily to the rotors being tweaked though if somebody is over torqueing the lugs each time work was done on the brakes. My GA would do the same thing at highway speeds and get worse when I applied the brakes. Retorqueing the lugs helped but it still would shake at 70. I eventually replaced the rotors and torqued the lugs properly the first time and its smooth at any speed now.

Welcome to AF grandam913.

It doesnt matter if you have $1000 tires,
if they are not balanced properly it'll shake at certain speeds.

If you are driving where it is snowy/slushy on the roads,
you could have ice and snow built up inside the rims throwing off the balance.

But I wouldnt rule out the axle shafts either .

I agree with Jim and XI but also check lug nut holles on each rim, if some of them are oval looking from too much torque that can cause a lot of problems, beleve me I am thinking to put back my black stock steel wheels I think they just sit on the hub better and if you have a nice rims and they are not factory then probably you are dealing with some engeeniring issues that could be creating problems for you at certain speeds. This is just my opinion. Or maybe she is afraid to go faster than 80 :)

Early tires had their speed rating symbol shown "within" the tire size, such as 225/50SR16. Tires using this type of branding were not to have been produced after 1991.

225/50SR16 112 mph, 180 km/h
225/50HR16 130, 210 km/h
225/50VR16 in excess of 130 mph, 210 km/h


Beginning in 1991, the speed symbol denoting a fixed maximum speed capability of new tires must be shown only in the speed rating portion of the tire's service description, such as 225/50R16 89S. The most common tire speed rating symbols, maximum speeds and typical applications are shown below:

M 81 mph 130 km/h
N 87 mph 140km/h Temporary Spare Tires
P 93 mph 150 km/h
Q 99 mph 160 km/h Studless & Studdable Winter Tires
R 106 mph 170 km/h H.D. Light Truck Tires
S 112 mph 180 km/h Family Sedans & Vans
T 118 mph 190 km/h Family Sedans & Vans
U 124 mph 200 km/h
H 130 mph 210 km/h Sport Sedans & Coupes
V 149 mph 240 km/h Sport Sedans, Coupes & Sports Cars


When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of new vehicles that have extremely high top-speed capabilities.

W 168 mph 270 km/h Exotic Sports Cars
Y 186 mph 300 km/h Exotic Sports Cars


While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed.

225/50ZR16 in excess of 149 mph, 240 km/h
205/45ZR17 88W 168 mph, 270 km/h
285/35ZR19 99Y 186 mph, 300 km/h


Most recently, when the Y-speed rating indicated in a service description is enclosed in parentheses, such as 285/35ZR19 (99Y), the top speed of the tire has been tested in excess of 186 mph, 300 km/h indicated by the service description as shown below:

285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 (99Y) in excess of 186 mph, 300 km/h


As vehicles have increased their top speeds into Autobahn-only ranges, the tire speed ratings have evolved to better identify the tires capability, allowing drivers to match the speed of their tires with the top speed of their vehicle.

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=35

Hey XI, how much did the CV Joints cost?

I too have a slight shake, more intermittent... its a pulsing feeling... it'lll go smooth.. shake.. smooth.. shake.. and so on... the process speeds up as I go faster... It feels like the wheels but I dunno.. could be wrong... I might just go re-tighten all the rims later today... dont want one of those babys to fly off haha :lol:

Does one of the front wheels make clicking sound when you turn sharply in one direction or the other? What is the mileage on the car? It sounds like you may have a warped disc brake rotor & had that problem on my Bonneville




Hey XI, how much did the CV Joints cost?

I too have a slight shake, more intermittent... its a pulsing feeling... it'lll go smooth.. shake.. smooth.. shake.. and so on... the process speeds up as I go faster... It feels like the wheels but I dunno.. could be wrong... I might just go re-tighten all the rims later today... dont want one of those babys to fly off haha :lol:[/quote]

Hey Gir, I cant remember exactly but I bought them from Napa. Probly check the prices at http://www.napaonline.com/ (http://www.napaonline.com/)

But from what youre saying its doing sounds more like a balance problem or the lugs are overtightend. They should be torqued to 100Ft lbs.

Thankx Jim for that trivial tire stuff :uhoh:

And also,
anyone having these kind of troubles right now should probley check thier tire air pressure.
As they could be extremely low due to the cold snaps we've all been having.

Just another :2cents:

Hey Gir, I cant remember exactly but I bought them from Napa. Probly check the prices at http://www.napaonline.com/ (http://www.napaonline.com/)

But from what youre saying its doing sounds more like a balance problem or the lugs are overtightend. They should be torqued to 100Ft lbs.

Thankx Jim for that trivial tire stuff :uhoh:

And also,
anyone having these kind of troubles right now should probley check thier tire air pressure.
As they could be extremely low due to the cold snaps we've all been having.

Just another :2cents:

Yea I have no idea how to gauge 100ft lbs :rolleyes: from my bare hands :iceslolan ... I got this nifty heavy duty lift in my garage from one of my mother's friends... ill put it to some use tomorrow and go all around and see if that clears it up.... I need to do air while Im at it, I think only 1 tire is at a good pressure .. the others dropped from all the ice/coldness heh