Ok, whenever I get to 45mph+ my car vibrates real bad. The door panels shake and my window clanks against the door, and it's almost impossible to look out the mirrors. I had my front motor mount replaced at a local shop, and this only helped the problem a little. Could this be from the rear motor mount? And if I were to get a set of mouter mount inserts, would that fix the problem? Any help would be appreciated...it is starting to drive me nuts.

are your wheels correctly balanced?

yes, I just got new rims and brand new tires, mounted/balances/alinged. And new tokico blues on all fours.

What kinda transmission do you have?

i would make sure your lugs are all tightened to spec. Maybe a couple are a little more loose than the others. Besides balancing the wheels, which you said was done already, that's my only guess.

its your alignment or balancing, someone messed up.
or a wheel weight fell off, could be lug nuts are loose too
take it back to where you you the alignment done and tell them to fix it FREE

I have the 5 spd tranny. My lug nuts are tourqued to specs, and im assuming my alignment is fine. I was thinking it was my mouter mounts, but would it vibrate all of the time and not just 45+ if it were my motormounts. Maybe I will being it back and complain that the alignment is not straight. Any other ideas?

those sticker kind of weights do fall off if the wheel is not cleaned in that area first (tire places do forget stuff)

Yeah, that does not sound like a motor problem. Does it do it in neutral when you rev the motor up?

Im thinking it would have to be the motor, because when up about 45mph and I let off the gas or put it in nuetral the shaking stops. It does not shake when im sitting at a stop light or anything. Whenever I take right turns and I am accelerating, then the shaking gets worse. When I am going around a left bend then the shaking gets better than it would be if I were going straight. Make sense?

I'm thinking it's probably suspension related; if it's a broken or bad motormount, the car would probably vibrate all the time. I'd have the alignment shop check it again. Is your car lowered? If so, do you have a camber kit? The toe setting could be off.

No the car is not lowered, but if it were the suspension wouldn't it shake when I was rolling at 90mph in nuetral? It only does it while I'm on the gas. IDK :shrug

Originally posted by Tman
wouldn't it shake when I was rolling at 90mph in nuetral? It only does it while I'm on the gas. IDK :shrug

Sorry, I missed that part. Hmmmm....

BUMP! Anyone? Please!

bump

Funny...I'm having the EXACT same problem. I have had my alignment and wheel balance checked by 3 different shops. I'm thinking I might go to a fourth. Only mine shakes horribly between 85-90, 120 and up it's smooth.

I noticed negitive camber wear on my rear tires, mabey this negitive camber is causing it, I'm going to space my camber kits out some more (even though according to the alignment shops it's aligned, the tire wear says otherwise) and see if it goes away.

I also think I have my rear slotted discs on the wrong way (instructions didn't say which way they should point). Mabey this could be causing it?

It's gotta be a motor mount. They could be broken or worn out. Check the 2 motor mount's and the 2 anti-roll mounts.

My mounts are good (plus they have ES inserts in them). I took off my rear wheels today and saw they had excessive negitive camber wear and the tires were pushed up in the middle on the side that had wear (as opposed to the other side being flat). So tomorrow morning I'm going to space out the rear wheel cams using some more washers from the ingalls kits and hopefully the problem will be gone (even though the dumb alignment shop was suppose to do this).

man that sucks...the bad thing is, tires aren't cheap. Well my alignment is definetly fine. Like I said, I had the front motor mount replaced. Maybe it could be the passenger side motor mount? If I get motor mount inserts, do you think it would fix the problem or not? I really dont feel safe driving it, I'm always concerned that something is going to fuck up soon. Thanks for the input guys.

Inserts can help bad motor mounts, but not broken ones.

Your problem sounds alignment related tman, take to a alignment shop ASAP.

aight, thanks man.

How's the condition of your tire? Even if the car is aligned, if the tires are "out of round," that could cause the vibration at higher speeds. Also, if the CV joints are going bad, that could contribute to the vibration.

my friends eclipse vibrates at 50mph+ cause his brake rotors are warped, dunno if thats your problem

I have brand new rotors on, no vibration when braking.

tires are brand new...and are in perfect shape. The rotors could be the culprit. whenever the ice thaws, i will take a look at it and/or bring it to the alignment shop.

I had the exact same problem, went to satan and got a passenger side motor mount (you might need more than one)for about 50 bucks and some change. It cleared up the problem. Good as new. The reason I believe it causes this vibrating is because the motor torques up when you accelerate and because the side of the engine is not mounted properly it lifts everything including the axle and throws off the balance of the the transmission... ie....one straight shaft(left axle) and one at a small, acute angle (passenger side) both spinning and kind of like a gyroscope it throws the whole thing out of balance. Sorry for my horrible ability to type what I mean, butt i hope this makes sense.

Originally posted by mastrcobb
I had the exact same problem, went to satan and got a passenger side motor mount (you might need more than one)for about 50 bucks and some change. It cleared up the problem. Good as new. The reason I believe it causes this vibrating is because the motor torques up when you accelerate and because the side of the engine is not mounted properly it lifts everything including the axle and throws off the balance of the the transmission... ie....one straight shaft(left axle) and one at a small, acute angle (passenger side) both spinning and kind of like a gyroscope it throws the whole thing out of balance. Sorry for my horrible ability to type what I mean, butt i hope this makes sense.

same prob here...you can't tell unless you can look close at the mounts...I had to repair the one at the firewall because no dealer in MD could get it for a few days, and I couldn't wait. Mine broke into 3 pieces. I welded it back together, and problem was gone.

At what speed would you guys with bad motor mounts car's vibrate? Mine is very bad around 85-90

I think I'm gonna have to run it by a shop, and just leave them with those two ideas on what the problem is.

Umm when I was replacing my stabilizer bar end-links today I saw that the CV joint closest to the tranny on the driver side had a hole in it and grease was everywhere.

Would this cause the car to vibrate at high speed?

Originally posted by WickedESi
Umm when I was replacing my stabilizer bar end-links today I saw that the CV joint closest to the tranny on the driver side had a hole in it and grease was everywhere. Would this cause the car to vibrate at high speed?

Yes.

did you cut your springs? :+

Originally posted by WickedESi
At what speed would you guys with bad motor mounts car's vibrate? Mine is very bad around 85-90

Just when accelerating at low speeds, very lightly in other gears. I also felt
it pretty bad when I slowed down...It was VERY obvious that something was wrong. Nevermind...I'm late reading this. You found your problem.

Just a question, but do you feel the clutch slipping on left hand turns?

No, thank goodness. (No crankwalk in my 420a)

Why would a cut CV boot cause vibration?

Originally posted by WickedESi
Why would a cut CV boot cause vibration?

A cut CV joint boot by itself doesn't cause vibration, but damage to the CV assembly parts (bearings, cage) can occur due to possible loss of lubrication and contamination by foreign matter. Since it's part of the drivetain (axle), it could could cause the car to vibrate at higher speeds. I'm not a professional mechanic, but this is what I've read, and learned from mechanic friends and family members. There are many possible things that could cause the vibration (damaged motormount(s), alignment, tires) and worn CV joint(s) is one of them.

hey man, this same thing happened to me. when i would turn right it would be fine...when i would turn left all hell would break loose and the car would vibrate like crazy. it turned out to be my lug nuts...2 had fallen off the front wheel and the other 3 were loose. Just go out there and see if u can turn them with a wrench or something....sounds exaclty like my problem.

I've had my wheels on and off many times since this whole thing started. Replacing the axle tomorrow morning, and if all is well, I can go the the track Sunday!

I replaced the axle and the car still vibrates at high speed, but it goes away after 110mph. I'm so !@$*ing confused. I even had the car aligned...again (4th time), and i slipped and told the mofo's I had replaced a tie rod, so my warrenty was voided and had to pay another $80.

I'm lowered w/ Sportlines and in the rear have the ingalls extreme camber kit, and I have the rear most cams spaced one more washer that the front cams (on the rear wheels), because I had the toe maxed out when it was even, and I spaced the rear one more to give me more positive toe, so I could adjust it to spec. Would this off balance cause any force to make it vibrate or something?

Problem Solved

Someone that aligned my car had spaced the rear cams of the rear A-arms 1 washer (thick ingalls washers that adjust camber by .5* each) thicker than the front cams in order to decrease the negitive toe. I removed the extra rear washers on the rear cams, which takes the uneven pressure off the bushings, as well as increases negitive toe (for straight line stalibility), and there is no longer this vibration at high speed. There is a little however just because my tires are visibily warped to shit because of the camber misconfiguration.

Moral of story

When adjusting the rear camber put an even number of shims on the front and rear cam. (Do adjust toe via the cams.)

awsome man! Well that takes care of some headaches. I'm still fiddiling with my car. I had my motor mounts checked and they are all fine, I think I have slimmed the possibilities down to a tie rod!

Hey Tman, I would jack the front of your car and grip the wheel at 9 and 3 oclock and wiggle back and forth and see if there is any play before the steering wheel moves. I think the inner tie rods are the culprit to a lot of the "unsolveable" vibration issues people are having.

Hey man I had the same problem as you. It turns out that my input shaft bearing and cv joint on the passenger side were shot. You can check it by jacking the front of the car up off the ground and spin the wheel. If you see your motor flexing back and fourth and feel the wheel binding during revolution then you most likely have the same problem. Good luck and if you have any further questions feel free to e-mail me.