cant get rid of the vibration

steve75

New Member

Dec 25, 2006

12

0

0

Sep 21, 2007

#1

• Sep 21, 2007

• #1

ok heres the whole story. i had a small vibration that started @90mph. its speed related NOT RPM. so the first thing i do is get my tires balanced. vib still there. so im thinking its ujoint or tranny mount. i have new u joints put in and i jack up the tranny and put in the new mount. now the vibration is 10x's worse. so i put the stock tranny mount back in. still 10x's worse. i pull the alluminum drive shaft and take it to get balanced. i put it back in. no luck. i turn the drive shaft 90 degrees then 180. still the vib is there 10x's worse. im running out of options so i check the motor mounts the upper and lower control arms, everything looks fine. so now im thinking when i jacked up the tranny i must have bent something like the tranny shaft. what do you all think?

 

Jaswir

Member

Mar 31, 2005

578

0

18

Orlando, FL

Sep 21, 2007

#2

• Sep 21, 2007

• #2

check bell housing bolts... could be the pinon bearing (i think thats what its called) in the rear end.. ive herd u get bad vibrations from that...


i had drive shaft lose... and i tighen them back up and then the vib got 10x worse... check bell housing bolts and there was 4 lose... i guess because of the drive shaft being lose for a couple days it shook it lose! tighten them up and went away!

 

Darkwriter77

Resident Ranting Negative Nancy

5 Year Member

Jul 1, 2005

314

281

134

Apache Junction, AZ

Sep 21, 2007

#3

• Sep 21, 2007

• #3

Output shaft bushing is wallowed out? Wiggle around on the front-end yoke of the driveshaft to see if it has a lot of play in the tranny.

 

G

GTOreturns

Well-Known Member

Oct 1, 2003

51

17

59

West Coast Best Coast

Sep 21, 2007

#4

• Sep 21, 2007

• #4

How old are the tires?

 

ryan218

In just 10 years, I'll be old enough to drive!!!!

Dec 28, 2005

0

1

38

columbus ohio

Sep 21, 2007

#5

• Sep 21, 2007

• #5

have your wheels checked to see if the true...the rear on on my SC wasnt...had a horriable viberation after 40 mph is when i started to notice it...

 

steve75

New Member

Dec 25, 2006

12

0

0

Sep 21, 2007

#6

• Sep 21, 2007

• #6

tires are acouple months old. its not the tire or wheels. i checked the bell housing bolts and they were all tight.

 

408gt91

Member

Apr 29, 2007

114

0

16

N.H.

Sep 21, 2007

#7

• Sep 21, 2007

• #7

possable wheel bearings or rotors?

 

ryan218

In just 10 years, I'll be old enough to drive!!!!

Dec 28, 2005

0

1

38

columbus ohio

Sep 22, 2007

#8

• Sep 22, 2007

• #8

you check that big ole chunk of metal that hangs a little in front of the pumkin? i still have no idea what to call it though..i think thats something ford used to help stop viberations? i know if its lose it would casue something like that.

 

hotcobra03

Active Member

Nov 29, 1999

969

4

39

poteet,tx

Sep 22, 2007

#9

• Sep 22, 2007

• #9

dude u didnt say what type of car you have,,,,,,,,first thing was anything changed when you first started feeling vib..............high speed viberations are normaly tires and driveline,,,,,,,,,,you have said you had them both done,,,,,,were tires balanced on car or off car???????i need to know a little more about the car

 

G

GTOreturns

Well-Known Member

Oct 1, 2003

51

17

59

West Coast Best Coast

Sep 22, 2007

#10

• Sep 22, 2007

• #10

408gt91 said:

possable wheel bearings or rotors?

Click to expand...

+1

Does it get worse with breaking?

 

ttop88

Member

Mar 12, 2007

42

0

6

indiana

Sep 22, 2007

#11

• Sep 22, 2007

• #11

Been there done that. If you havnt put front wheel bearings in the car start with them. If it is still there put all new bearing in the rear end. It is a inner bearing race going bad. It took me a year of chasing to find mine in the carrier bearing.

 

steve75

New Member

Dec 25, 2006

12

0

0

Sep 22, 2007

#12

• Sep 22, 2007

• #12

its a 93 cobra. it dosent get worse with braking. the vib came from no where. i havent changed anything on the car. the tires were balanced off the car. i didnt even know you could balance them on the car.

 

hotcobra03

Active Member

Nov 29, 1999

969

4

39

poteet,tx

Sep 23, 2007

#13

• Sep 23, 2007

• #13

yes on the vec. balancing is at around 120mph,,,,vs 60 to 80 mph...try to find out if its rpm or speed related.......drive car till vib, starts,,place into neutral.......does car still shake????????while you are coasting,,,rev engine up and down...fell anything?????

 

steve75

New Member

Dec 25, 2006

12

0

0

Sep 23, 2007

#14

• Sep 23, 2007

• #14

the vib is 100% speed related

 

Blk91stang

Member

Jan 3, 2003

607

0

16

North Brunswick, NJ

Sep 24, 2007

#15

• Sep 24, 2007

• #15

Here's what I did. Put your car on a lift where the wheels hang and preload is on the suspension (Might be hard since i think only in-ground lifts have this capability. It grabs the car by the rear axle from underneath and on the front control arms)

From here just get your car up to 90mph on the lift and see if the vibration is still there. This will rule out EVERYTHING except for your driveline. Now you can start your testing from there.

This is what I did and was a HUGE help since I ruled out the suspension, tires, wheels pretty quickly. From there it could only have been a few things. Turned out to be my stock driveshaft after messing around with it. Aluminum one cured it.