dvls-7

Looking for any fresh ideas or suggestions.....I get a very bad vibration from 80mph +. Ive eliminated the wheels by rebalancing, rotating and even putting stocks back on, and it still does it. Im running out of things that could cause it, im thinking it might be the drive shaft or that i might have to get another alignment but i don't think its that cause it is something that just started happening. Any help is very appreciated. Thnx.

Snufelupogus

iTrader: (2)

wheel barrings? aligenment? is that the only time there is a vibration?

niner

what kinda vibration is it? how sensitive of a driver are you? do you feel it in the steering wheel? or seat? or body of car?

it could be u-joints in the driveshaft or the shaft itself. it could be one of the halfshafts. it could still be tire balance or slightly bent wheel. it could just be a bad tire because of many reasons, like force variation or minor defect or separation. are all suspension and steering components good?
finding the root of the problem to something like that can be a big pain in the ***. trial and error is sometimes the easiest way to find out whats wrong.
tried rotating the tires around to different spots?

a good mechanic should be able to figure it out. most balancers only guarantee to be accurate up to about 80mph. maybe try a different shop.

akageals

I had severe noise and vibration in my '89 TII. The car was also shooting left and right all over the place. New tires/alignment and now it drives like new.

Todd

Hot_Dog

Oftentimes, it's very hard to pinpoint the source of a vibration. I've once had a problem similar to what you're describing. It turned out it was the rear end on my 90 GXL. This happened probably about 5 years ago when the car had about 140K miles on the odometer. I bought a low mileage LSD rear end from an 86 GXL as a replacement. The 90 GXL wasn't equipped with LSD, BTW. I would recommend first checking the driveshaft, half-shafts and rear wheel bearings. I've found that the driveshaft and rear wheel bearings typically have a lifetime of about 100K miles. Of course, there's always exceptions, and some will go longer than others. After that, if there's a lot of "slop" in your existing driveline, than ever more reason to suspect the rear end. BTW, if you need a good used rear end (86-88 NA LSD), i've got one that's available.

Hot_Dog
90 RX7 GXL
02 RSX-S

Samps

If the vibration happens with your foot on the gas but goes away with your foot off the gas then you driveshaft or diff mounts are suspect.

If the vibration is in the steering wheel, the front wheels, tires, bearings, struts, bushings, springs are suspect.

If the vibration is in the seat, the rear bearings, bushings, diff mounts, shocks, springs, wheels, tires, alignment is suspect.

A good description of the vibration would help. When does it vibrate? What have you done to the car lately? How are the tires? Do you drive on bumpy roads?

An alignment can be thrown off by one large pot-hole 1 minute after you had it aligned!

Turbonut

iTrader: (1)

This may be "old hat", but what I suggest is to jack up the rear, under shock area to maintain level height. You can secure vehicle on stands, but you want to keep rear supension loaded..as normal. Just jack up the rear wheels to clear ground. Get it up to speed to see if any vibration noticed. That way you can eliminate front end, etc. Also, look at mounts to be sure motor/trans/driveline in proper alignment.

dvls-7

Thnx for all the responses. To answer the questions that were asked....All front end components are new with energy suspension rubbers. The vibraton is felt in the steering wheel and its VERY noticeable in the dash as well. Im thinking it is in the drive line somewhere, problem now is to try and pin point it.

Barwick

rear wheel bearings (or even front)... fronts can be tightened up if they're too loose, rears must be chaned if they're vibrating.. jack the car up and try to jiggle the wheels.. they shouldn't jiggle

version13

There was a vibration in my car at about 80+mph also, it turned out to be a poor engine mount. just needs realining, lots of work also.

dvls-7

Thnx for that suggestion, thats something i was over-looking

Amur_

Both of these articles are posts from rec.autos.rotary. I don't recall who the authors were but I'm certain they wouldn't mind that these were shared...

----------------------------
> It turns out that the front wheels weren't properly balanced, and after getting
> them redone, the hopping is all gone (whew!)
> But, the shop told me that my wheels (lopsided?) were a little to blame.
> They've never even hit a curb before, I wonder why that might be.....

Maybe the shop is trying to make excuses for their lack of expertise.
Like I said before, find a shop that does high performance front end
work.

You can check yerself for wobbly wheels, preferably with a dial gauge,
but the following is almost as accurate. Get the wheels off the ground
(preferably the whole car up on jackstands). Clamp a pencil in line with
a vise-grip. Using something solid, like 4x4s, a stack of Bibles,
whatever, make a stand up to the level of the rim on which you can lay
the vise-grips. Put the pencil point agianst the rim inside the lip
(which may be dinged) and gently rotate the wheel. The wheel should
touch all the way around. If it does not (and assuming the bearings are
good) you have a buggered wheel. Throw it away.

Do the same thing on the tread at about the midpoint, half way up the
wheel. If the tire is out of round or flat spotted, you need to have it
shaved, then balanced. (Do this after a run to heat the tires, they will
flat spot sitting over night.)

If a front end shop does not shave tires, they are NOT into high
performance and you need to find another shop, although it is rare that
a new high performance tire needs to be shaved. Find a GOOD shop and pay
them whatever they ask, bow and scrape, kiss their ***, whatever it
takes to get on their right side and stay there.

-----------------------------

> Anyone, here's a problem I'm dealing with for the last few months.
>
> Problem:
> Steering wheel shakes when I brake at speeds above 50-60 km/h. On some days the shaking is worse than on other days. Steering wheel is fine when driving normally or braking at low speeds.
>
> Things I've tried or noticed:
> -replaced brake pads and rotors with new ones. Did not have any effect on problem.

> -rotated the tires, made sure tire pressure is ok. Did not have any effect on problem. My tires are about 1.5 years old with about 20000km wear so they are still relatively new tires. I inspected the tire treads, they look good with no unusual wear on any of them.

> -the steering rods(tie rods?) do not appear to be loose or worn.
>
> Any ideas what could be the issue? My car is 9 years old about 100000km driven so I'm thinking it might be a worn wheel bearing or other worn part in my steering assembly.
================================================== ==============================


I had the exact same problem as you do, and tried the same 'fixes' you have, including all new wheels and tires, all six new balljoints in front end (2 control arm, 4 tierod), solid rear-steer eliminator bushings, polyurethane bushings in the front, replace driveshaft, replaced all 4 shock absorbers, and swore a helluva lot. Nothing helped!!

I finally fixed the problem after seriously considering selling the car--not that anyone would have wanted it!

The problem was traced to improperly tightened wheel lug nuts. The procedure used to tighten lug nuts is critical if you wish to be able to drive at all speeds with no steering shake. This is especially critical for aluminum wheels which do not have steel inserts around the lug nut holes. These inserts are for reinforcing the metal around the nut, to prevent stretching.


If you wish to know the proper technique for tightening lug nuts, ask me (on the newsgroup) and I will tell you. It's a little lengthy, but if you're interested in how it's really done I'll tell you. Hint: It's not nearly as simple as you thought! (Or as simple as you figured while watching your friendly neighbourhood "certified" auto mechanic do it.)


I have yet to meet ANY certified auto mechanic who has the foggiest idea of how to tighten lug nuts properly.


It's pretty easy, but you have to do it right.

First jack car up to height where the wheel will go on without touching the ground. Then install all lug nuts and tighten by hand, using only the socket--no wrench.

Knowing what the final torque is, tighten the nuts using a torque wrench in the proper sequence, but in 5 foot-pound increments. You know that for 5-nut wheels, you tighten #1, then #3, then #5, then #2 and finally #4. But the real trick is to only tighten them in 5 ft-lb. Increments so that the retaining pressure is applied evenly to the wheel hub. Keep working around the wheel so they have all been tightened to the required torque--and do it without lowering the wheel onto the ground, or using the brakes. Have someone hold the wheel if you have to.

Suppose the spec says "50 foot-pounds".

So, with a torque wrench (I like the bending-beam type, I have no idea how repeatable the snap-action ones are) first install wheel, then run on lug nuts by hand using only the socket. When all nuts are on, tighten by hand using socket. Make sure the wheel is seated properly before continuing

Now get torque wrench and tighten in 1-3-5-2-4 pattern (for 5 nut wheels) or 1-3-2-4 for 4 nut wheels. Tighten all nuts first to 5 foot pounds. Next, starting again at #1, tighten all nuts to 10 foot pounds. Then start at #1 again and tighten all nuts to 15.

Keep going until you reach required torque--then go around AGAIN, reapplying the final torque to all lug nuts.

I find that this method allows the wheels to run at all highway speeds without the steering wheel shaking back and forth. However, you must start with round wheels and round tires, and the combination has to be properly balanced.


Reason is that just slapping the wheel on and reefing up the nuts applies pressure unevenly to the wheel hub, even if all nuts are torqued evenly. The metal squeezes out slightly from around the first few lug nuts, and the stud hole circle enlarges. This causes warping. Now heat the hub up nicely with a scalding hot brake disc, and the unevenness in wheel spoke length will become really obvious to the guy with his hands on the steering wheel.

Some aluminum wheels, like my Eagle 5-spokes, do not have steel inserts around the lug nut holes. This makes the tightening procedure all the more critical, and the final tightening torque must be lower, regardless of what the manual says. I believe my Mazda shop manual specifies lug nut torque at 70 to 80 ft-lb., but in reality, the 16" Eagle 5-spokes must be tightened, sequentially, to only 50 ft-lbs--otherise the steering shakes really badly, to the point where my hands get right bloody numb after 20 minutes. If I do it properly, the wheel is dead smooth at all speeds.

BTW, sometimes I have to do it twice to get it right! You don't have to be quite as **** with the rear wheels, but I'm absolutely picky about the way I tighten the fronts. Lean down so you can really read the torque wrench scale bang-on when doing the fronts. Get someone else to hold the wheel if you have to while tightening.

Apparently engineers have known about this method for tightening high pressure caps and end plates for something like 100 years

Barwick

what the #%*(?!?!? That sounds completely screwed up.. either the wheels this guy's talking about are completely SUCKY or something is seriously messed up here..

I've never seen a race car driver do that (and I'm not talking about the guys on TV with the one nut knockoff wheels either).

Seriously I don't think they're that sensitive, unless you've got some really really really really really crappy wheels.

Nick86

iTrader: (1)

My dad and I had the same problem on his 535i. It was a very noticable vibration throughout the whole cabin, that was made worse at full throttle. It turned out to be an exhaust mounting problem. The whole exhaust was torqued so much that on one side, the hangers on the exhaust were touching the hangers on the car. The rubber mounting blocks/donuts were not being used at all. Once we undid the exhaust and got it hanging properly, there was no vibration anymore.

Crionics

It sounds like a front end problem to me. Just takle the car somewhere and have them check the balance, alignment and your suspension. Jack the front end up and try to rock the wheels...any play and you should suspect your bearings/hub or tie rods or something...

Or go buy a haynes manual and walk through the troubleshooting section.

until you post things that you've done recently, though, no one here will be able to help.