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Bad vibration....Need help.

Posted: Thu Feb 17, 2011 7:02 am
by ThatOneBigKid
So I have this stupid vibration that I can not figure out. I can drive for about 10 minutes before it starts. The car only shakes when I press the accelerator in 4th, 5th or 6th gear at 2000 rpm or higher. It doesn't shake if I'm at crusing at a constant speed or if I let off the accelerator.

Any help would be appreciated, I'm lost on this one :?

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 11:19 am
by Steve@Tasca
So it would do this in fourth at 4000 rpm just the same as if you were in fourth at 2000 rpm?

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 12:12 pm
by ThatOneBigKid
Hey, as long as I am hitting the accelerator it is vibrating bad. Just drove it on lunch break and I felt a minor vibration now in 3rd gear too.

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 12:43 pm
by Redlineracer12
You could try rotating the tires if it's mainly at higher speeds.

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 12:43 pm
by blcksvt2003
ThatOneBigKid wrote:Hey, as long as I am hitting the accelerator it is vibrating bad. Just drove it on lunch break and I felt a minor vibration now in 3rd gear too.

engine mounts ? idk, i had a blown passenger side and never noticed any vibrations and mine was dryyy as a bone :/

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 1:28 pm
by Steve@Tasca
What happens if you rev it in neutral?

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 6:01 pm
by ThatOneBigKid
Redlineracer12 wrote:You could try rotating the tires if it's mainly at higher speeds.
Rotated tires a week ago and the tires are only a few months old. I have rotated them ever 4000 miles. Also it only vibrates if I am accelerating. If the wheels were out of balance it would vibrate all the time.
blcksvt2003 wrote:
ThatOneBigKid wrote:Hey, as long as I am hitting the accelerator it is vibrating bad. Just drove it on lunch break and I felt a minor vibration now in 3rd gear too.

engine mounts ? idk, i had a blown passenger side and never noticed any vibrations and mine was dryyy as a bone :/
I thought this too but haven't been able to check them.

Steve, If I rev in neutral its no different than normal. No vibrations, noises or anything out of the normal.

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 7:23 pm
by blcksvt2003
transmission..clutch..idk im not a real mechanic :?

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 8:53 pm
by spots25
that's an odd one, but I'd replace the passenger side motor mount. It's $40, 15 min, and they're known to go bad and cause weird problems

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 11:12 pm
by bflesher
Mounts would be a good start, maybe the cv joints/shafts since it is under load maybe one twists or wobbles. Or maybe another front end piece is worn and allowing enough defection to cause a vibration.

Re: Bad vibration....Need help.

Posted: Thu Feb 17, 2011 11:23 pm
by tgnorman
spots25 wrote:that's an odd one, but I'd replace the passenger side motor mount. It's $40, 15 min, and they're known to go bad and cause weird problems
Slightly more expensive on the SVT, but definitely a good place to start.

Re: Bad vibration....Need help.

Posted: Fri Feb 18, 2011 8:28 am
by Steve@Tasca
ThatOneBigKid wrote:
Redlineracer12 wrote:You could try rotating the tires if it's mainly at higher speeds.
Rotated tires a week ago and the tires are only a few months old. I have rotated them ever 4000 miles. Also it only vibrates if I am accelerating. If the wheels were out of balance it would vibrate all the time.
blcksvt2003 wrote:
ThatOneBigKid wrote:Hey, as long as I am hitting the accelerator it is vibrating bad. Just drove it on lunch break and I felt a minor vibration now in 3rd gear too.

engine mounts ? idk, i had a blown passenger side and never noticed any vibrations and mine was dryyy as a bone :/
I thought this too but haven't been able to check them.

Steve, If I rev in neutral its no different than normal. No vibrations, noises or anything out of the normal.
If it doesn't do it in neutral then it's driveline, not engine or clutch.

I'd look at wheel bearings of the right side half shaft bearing, more likely the latter.

Re: Bad vibration....Need help.

Posted: Fri Feb 18, 2011 8:30 am
by Steve@Tasca
spots25 wrote:that's an odd one, but I'd replace the passenger side motor mount. It's $40, 15 min, and they're known to go bad and cause weird problems
An OEM passengers side mount for an SVT is $120.00 and I'd be shocked if there was an aftermarket copy, an OEM Zetec mount is $75.00.

Everything I've heard about aftermarket Zetec mounts says they're garbage but on the plus side you'll get REALLY good at changing that mount if you go that route. :D

Re: Bad vibration....Need help.

Posted: Fri Feb 18, 2011 9:02 pm
by bflesher
I'm not sure on the quality of the aftermarket motor mounts but from what i hear/read is if you replace them with aftermarket, and the dogbone also, you vibrate like hell. Thats with the poly ones or otherwise stiffened. That occurs at all rpm's and at idle though.

Re: Bad vibration....Need help.

Posted: Sat Feb 19, 2011 5:40 pm
by ThatOneBigKid
Turned out to be the CV Shaft. Just got done replacing it and it drives smooth as glass. Big thanks to Steve for the CV Shaft!

Thanks for everyone's input.