Hey everyone im getting alot of vibration on the highway wondering what could cause this hoping it ismt tie rods or anything of that nature i recently just replaced the clutch on it the way i did it was i dropped tge cradle an held the motor up with my cherry picker ive marked all mounting points of the cradle so i would line it up exactly when i reinstalled it could the alignment be off by just alittle ???

slight misallignment usually does not cause vibration .check your tires for balance and your tie rod ends and ball joints .these can look good but a little slop will mess things up .

It could be simply the wheels out of balance. Just take the car to belle tire or something and have the wheels balanced to see if it goes away

Hit any curbs lately? Had to deal with this on a DSM acouple of years ago and it was a bent wheel.

If you have just started driving the car (never driven it since you bought it) and has the same tires on... could be Fix-A-Flat. Just a thought

Steve

84-87. Check for play in front wheels. Could be bearings or spindle nut not as tight as it needs to be. Mine used to vibrate a lot at freeway speed after I replaced the front hubs/rotors. After tightening up the nuts on the spindle it's gone.

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Dave

www.ltlfrari.com

balance your tires.

If you store it, could be flat spots on tires that wont go away. First determine if its in the steering wheel or the seat. That will tell you if its the front or rear. Go from there.

I have a similar issue on my car. I just got the car and at around 65 and up the entire car will shake. It doesn't seem to be in the steering though. The rear tires are new so they should have been balanced recently. What should I check first?

first check that the wheel nuts and wheels are securely and correctly fitted - then check that they are balanced - do you need new bushes i.e old rubber ones need replacing preferbly with poly.


jon

Do you have the stock wheels on your Fiero?

If not, do the wheels you have installed have the proper 57.1mm center bore?

If not, are you using the correct hubcentric ring spacers to center the wheels?

I recently installed a new set of aftermarket wheels (with track tires) and I didn't yet have the correct hubcentric ring spacers. I thought if I very carefully centered the wheels when I put them on and tightened each lug nut bit by bit that the wheels would be okay. Wrong! The car vibrated like crazy. I then got the correct 57.1 to 73mm hubcentric ring spacers for these wheels and put them on. HUGE DIFFERENCE!

Don't let anyone ever tell you that hubcentric ring spacers are not necessary to use with wheels which have a larger center bore than the factory wheels.

[This message has been edited by Patrick (edited 09-24-2012).]

The most common cause of vibration is out of balance tires. The tire stores typically hire cheap, ignorant labor that don't know how to use the balancing machines properly. Go to someone you can trust for a balancing job. If that doesn't work get the car off of the ground and try to wiggle the tire to discover any play or looseness. A worn steering rack, ball joint, tie rod end, inner tie rod, control arm bushing or wheel bearing can give you the symptoms that you describe. In my case I solved the problem with a balance job but after replacing the upper control arm busihings with poly.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

I just bought the car so unfortunately I don't have a lot of information about it. I can tell that the rear tires are almost brand new and the wheels look to be the stock ones. I'll get the car on jack stands and take off the wheels and have a look at everything when I get a chance. If I don't see anything obvious, I'll take the car to get the tires rebalanced. The front tires, although not new, have relatively new looking weights on them though.

quote Originally posted by pontiacfierokid1985: Hey everyone im getting alot of vibration on the highway wondering what could cause this hoping it ismt tie rods or anything of that nature i recently just replaced the clutch on it the way i did it was i dropped tge cradle an held the motor up with my cherry picker ive marked all mounting points of the cradle so i would line it up exactly when i reinstalled it could the alignment be off by just alittle ???

This guy posted this on 5/8/11 and had a half dozen replies and here it's 9/24/12 and he never posted again in this thread. No nothing, did any of these replies work, we will never know. Let's face it people ask question and members take the time to answer the questions and then they can't take a few seconds to let others know what works and what doesn't. Sorry if I hurt anyone's feeling

After I drive my 86 GT for about a 1/2 hour, the engine starts missing. This occurs at higher speeds, as well as shifting through the gears after a stop.
I've changed many parts (distributor, plugs, idle air control valve, injectors; had the throttle body cleaned and the sensors tested).
I have read that the ICM some times causes the problems above, so I just purchased a new delco part.
Am I missing something?
Incidentally, when all the sputtering occurs, the speedometer fluctuates wildly.
Thanks!
bb

quote Originally posted by Bruce: Am I missing something?

Yes, apparently you are. Why are you posting about your engine issues in a thread about wheel vibration?

[This message has been edited by Patrick (edited 09-24-2012).]

Well I checked the lug nuts and they are all solid so I guess I don't get lucky there. The spindle nut is larger than I have a socket for so I can't check the torque on that yet. I did notice that all the tires have a weight on the outside and one on the inside of the rim and not on the same clock location. Is that normal?

Also, the two front tires are not matching. Could this be the cause for high speed vibration through the car?

Thanks,
Ultimoblaze

I have never driven a car with miss-matched front tires, but I can't believe it's a good thing. Do you feel the steering pull at all?

No, it drives straight and the wheel doesn't seem to shake but rather the whole car. It's more of a pulsing shake though. So it will shake for a second then it will be smooth for a second then shake for a second etc.

I don't like driving with mismatched tires either, but they both still have similar amount of tread left.

So I drove it again today and noticed that under heavy acceleration it seems to have a shake too. This leads me to believe that it is one of the rear tires and that one is probably out of balance. Luckily, my friend has a Fiero with stock wheels on it, so I'm going to swap with him and see what happens.

I'm no mechanic but I have an 86 GT with a stuck front brake that caused a serious wobble when it first started sticking. At least I think that's what was causing it. It has stopped now.

quote Originally posted by ltlfrari: 84-87. Check for play in front wheels. Could be bearings or spindle nut not as tight as it needs to be. Mine used to vibrate a lot at freeway speed after I replaced the front hubs/rotors. After tightening up the nuts on the spindle it's gone.

I just did this!

I had a shake come up recently, and even went as far as to rebalance my wheels. Quite literally an hour ago I just finished up checking everything on my car. I have less than 15,000 miles on the setup, and found my front wheel hub nuts to not be tight enough. After spinning and tightening them, I took her for a test ride. No more shakey, shakey.

Tony

I swapped my rear wheels with my friends car and that didn't help. I noticed after driving his that the shake I feel toward the top of each gear is pretty bad. When I had the car off the ground I tried to twist and tilt the rears but they wouldn't budge. I'll swap the front wheels too for completeness, but I don't think wheel balance is the problem.

I looked at the nuts on the rear under the cap which are the spindle nuts right? They look like 27 mm compared to my largest which is a 24 mm so I'll have to get that socket. The fronts have what appears to be some sort of cap of over the nut. Do I just pry that off to get to the spindle nut?

What bushings do you think would allow shaking like described?

Would worn transmission/engine mounts do this?

Thanks,
Ultimoblaze

Well I swapped the fronts with my friends car too. I now have all four of his wheels. The high speed shake has gone away. So my unmatched front tires aren't working well together or they are unbalanced. I also noticed that they are the wrong size (195 vs 215). I'll take them and get two new tires put on and that should fix it.

This didn't solve the "bouncing" feel I get from the rear when accelerating though. I guess I'll start a new thread to investigate that issue. Thanks for the help guys.

Start with the cheapest easiest first. Have the wheels and tires checked for balance and runout. Its pretty common for even brand new tires to be out of round. I had a friend who bought a brand new Charger a few years ago have 3 out of round Goodyear tires from the factory. The dealer replaced them and it was perfect. I bought 4 new Sears tires for a Lincoln that were all bad. Replaced them with BF Goodrich and it was great. I had a Shelby Mustang that had a couple of out of round tires I had ground true (they shave off tread with like a lathe).

However, I just bought the car and those are the tires that are on it. I looked closer at them and not only are they not the same brand, but one is a treadwear rating of 620 and the other is a 240. That should be a pretty significant difference in rubber hardness. Additionally, the 240 rated tire has an asymmetrical tread pattern and it was put on wrong (I put the wheel on and read "This side faces in"). They are also 195s which as far as I know are too narrow for any Fiero. At this point I might as well get 2 new tires.

FInal update: I bought new tires and had them put on today. One of the tires had fix-a-flat in it. That's all I needed to hear to know what caused the high speed vibration.