Whole lotta shakin' goin on

[rlux4]

I haven't been able to figure out what's causing this problem, so I'm hoping I can get a clue from the gang here.
In 2nd gear between 2500 and 2800 rpm's my car starts to vibrate/shimmy. It feels like it's in the drive train, not the wheels. I have fairly new ball joints, flex disc and recently took the u-joints apart and greased them. The wheel bearings were greased about 10,000 miles ago. This only happens in 2nd gear and only between these rpm's. I recently replaced the flex joint because the old one (25,000 miles after replacement) had torn through in a section. I thought that may have been causing it, but the problem still remains.
Any thoughts?
Ron

[maytag]

let's see if it's speed related, or engine-load-speed related.
Does it do the same thing in 3rd or 4th at 2500-2800 rpm?

[124JOE]

paint the driveshaft go for a short cruze and see if some paint is missing

[So Cal Mark]

did you remove the front driveshaft from the rear?

[rlux4]

It only happens in 2nd gear at those rpm's.
I replaced the carrier bearing when I did the tranny, clutch disc, pressure plate and throw out bearing replacement shortly after I got the car, about 25,000 miles ago. The driveline sections were separated then, but this just now started. Seems like if I'd not put the driveline back as it was originally it would have showed up before now.
Ron

[So Cal Mark]

since you replaced the carrier bearing, do you have the driveshafts out of phase?

[rlux4]

Not quite sure what you mean by out of phase. I believe I put it back together the way it came apart, and like I say, this was about 25,000 miles ago. My thinking is that if I had mistakenly put it back incorrectly it wouldn't take that long for it to act up. And only in this narrow band of gear/rpm combo. I'm not saying I'm right, that's just my thinking.
I had a machine shop press the new bearing on the drive shaft btw. It was the whole unit, bearing and cushion. They look to be in good shape still.
Ron

[So Cal Mark]

well, you wrote that you recently replaced the carrier and disassembled the ujoints. To me, 25000 miles isn't recent

[htchevyii]

I think he just did the flex disc. Hope you get it figured out, things like that can drive ya nuts.

[rlux4]

Yes, I wrote that I'd just replaced the flex disc. The tranny, clutch, and carrier bearing were done shortly after I got the car. I should say that it isn't shimmy-like, it's more of a vibration through the drive train feeling.
Ron

[seabeelt]

I would check the guibo again as it is readily seen without taking anything apart. I would think that tranny or clutch would be making more noticible area specific noises. How about the drive shaft bearing support or tranny support brackets. There is also the rubber tranny mount just in front of the Guibo.
r/

[narfire]

I have a vibration at speed in my driveline as well. I suspect I did not put the driveshaft back exactly the same orientation after changing out the pinion seal last fall. Stupid mistake on my part(did not mark) so I'm going to rotate the drive shaft 180 degrees at the rear diff. and reconnect and see if that works.
Perhaps something like that is happening with yours Ron as I have read the shaft is balanced to a certain position and one should mark the shaft and connection points to keep the shaft vibration free (for the most part) if taking the driveline apart.
Chris

[leeputmanjr]

Ron-

This reminds me of the old joke where they guy goes to his Doctor and tells him it hurts when he moves a certain way, and the Doctor simply tells him not to move that way!

- Lee

[azruss]

Chris, the "out of phase" on the driveline is the front to rear section. rotating the driveline at the diffy wont do anything for you. you need to disassemble at the u-joint between the 2 sections and rotate 180.
As far as the pillow block, just replacing the bearing will not solve the vibration issue as it is the rubber bear support that breaks down. Dont know if you replaced the whole pillow block or just the bearing.

[124JOE]

I would check the guibo again as it is readily seen without taking anything apart. I would think that tranny or clutch would be making more noticible area specific noises. How about the drive shaft bearing support or tranny support brackets. There is also the rubber tranny mount just in front of the Guibo.
r/

i think you fellas should look at the tranny mount real good