My vibration issues...still

[COramprat]

I'm trying to decide what is causing some drive train vibration. I normally get the worst of it in 5th around 50-60mph. On occasion I get it very lightly in 3rd. It tends to go away if I shift at just the right time or after a few miles of driving and reshifting form neutral to 5th. I'm sort of ruling out the driveshaft now because it goes away if I put it in neutral so I'm starting to think something in the tranny. I don't think it is a clutch or flywheel issue either due to the same fact that it disappears in neutral or when the clutch is disengaged. Any ideas?

 

[Hunter-White]

vibration

I'm on my 4th mustang...They have all had vibrations of some sort or another. I replaced my rusty pullies and it seemed to help some motor vibration. On my other cars I changed to an aluminum driveshft which helped a tremendous amount..that is my next purchase.

 

[COramprat]

I'm on my 4th mustang...They have all had vibrations of some sort or another. I replaced my rusty pullies and it seemed to help some motor vibration. On my other cars I changed to an aluminum driveshft which helped a tremendous amount..that is my next purchase.

I already have the aluminum DS for about 2 years. This is something that started about 6 months ago. I'm just wondering if something in the tranny would cause the vibrations. It has new tranny and engine mounts so I don't think that is it.

 

[DTNODYA]

Check your engine mounts. I had a vibration the same as you describe ... changed the U-joints, alignment, trans mount, and more. Got frustrated until I discovered that the motor mounts were shot and this caused the entire drive train to be "off" causing vibration through the drive shaft.

Just a thought ...

 

[COramprat]

Check your engine mounts. I had a vibration the same as you describe ... changed the U-joints, alignment, trans mount, and more. Got frustrated until I discovered that the motor mounts were shot and this caused the entire drive train to be "off" causing vibration through the drive shaft.

Just a thought ...

See last line of post above yours.

 

[281CI96Coupe]

Check your engine mounts. I had a vibration the same as you describe ... changed the U-joints, alignment, trans mount, and more. Got frustrated until I discovered that the motor mounts were shot and this caused the entire drive train to be "off" causing vibration through the drive shaft.

Just a thought ...

Yep. I was just about to say the same thing. Buddy of mine broke his motor mounts in his vert, every time he would accelerate fast, you can feel everything shaking under your feet. Replaced them with some Polyurethane's the only vibration he gets now is a little because they are stiff lol.

 

[COramprat]

THE ENGINE MOUNTS ARE NEW!!!!

 

[DTNODYA]

I missed that ...
I would say trans mounts but I'd be preachin' to the choir ..

I guess, if you already haven't, you could check to make sure the two little weights are still on the driveshaft.

 

[COramprat]

Thing is I don't think it is the DS unless my deductive reasoning is off. The vibration goes away coasting in neutral or when the clutch is engaged. If the DS was the culprit I figure I would have vibration all the time. I've been through the bad U-joint problem and this is a little bit different. Would an egged out tail shaft bushing cause it?

 

[joshjwc9]

Im watching this thread too, as my car does the same thing at 35 in fourth and 50 in fifth. It seems like it is missing but my COP's and plugs were perfect yesterday when I checked them. But I have stock mounts and stock DS.

 

[OV10stang]

I've been thru the vibration deal already... Done the driveshaft, engine mounts, etc... My engine has a vibration that ranges from 2200 to about 2400rpms. I've learned to live with it. When I redo the engine, I will make sure everything is balanced perfectly.
If you push in the clutch, and the vib goes away, then it's the engine, like mine. I've even done a clutch since, with billet steel flywheel, and still have the vib.
My brother's 89 5.0 had the same prob. He has since installed a balanced, forged shortblock assy, no more vibrations.

 

[DLFD911]

A friend of mine had issues with his harmonic balancer. It was also RPM related. Just another thing to check.

 

[DTNODYA]

Thing is I don't think it is the DS unless my deductive reasoning is off. The vibration goes away coasting in neutral or when the clutch is engaged. If the DS was the culprit I figure I would have vibration all the time. I've been through the bad U-joint problem and this is a little bit different. Would an egged out tail shaft bushing cause it?

Well, as long as my deductive reasoning isn't off, it's gotta be something from the transmission to the rear wheels. Rear axle?? Maybe the tail shaft bushing? (I dunno either) .. I'm not a trans expert but it sounds like something is funny with your trans. Is it a 'wobble' type vibration (out of balance tires, wrong tire pressure, etc) or is it a 'floor shaker' type vibration (like the driveshaft is bouncing around) lol .. don't know how else to ask.

 

[fast97gt]

from experience if it was your u joints and it started six months ago it would be so bad now you couldnt stand it. but on the other hand it could be your trans. maybe some bad needle bearings or something