Bad vibration at speed, everything replaced.. What could it be?

[econti]

Brief recap:
I bought a LSD, and to install it pulled the driveshaft out. The unis were stuffed as was the CSB and flex disc, so that was all replaced.
Once back together, I found there was a vibration above about 65km/h, 40mph or so.

Bought a new CSB, fit that and preloaded it, had the d/s rebalanced again, still the same vibration.

I then bought a new clamp ring thing that screws on the end and binds the splines in the middle together, and fit it today. Now there are a multitude of clunks at every speed, and a massive vibration above 55km/h or 35mph.

What can be wrong?
The vibration has only started since I have done the driveline work. There was none before.

Can the diff be causing it? I still have the old open unit under the house, though it is an absolute pain to swap diffs.
I just don't know

[e30jake]

I've had a similar problem since I swapped a diff and installed a new driveshaft. With mine, the vibration was worst at ~55mph with a 4.10, ~70mph with a 2.93, and ~60mph with a 3.46 ratio diff. I'm wondering if my collar nut is loose? Feels similar to a bad CSB but that is new and I messed with the preload. I'm interested to find out more about this. Sub'd

[econti]

Well, I'm halfway through swapping diffs back to the original open. Hopefully that fixes it.

In regards to the swap, which is an awful job trying to get them to line up - thoughts on grinding a taper to the end of the diff mount bolts? I feel as if it'll make them way easier to locate into the holes

[econti]

Bump.
Swapping diffs did nothing.
Swapping wheels did nothing.

pls help

[KIRIEIW]

Did you mark the driveshaft when you removed it? When you split it in half, it needs to go back together EXACTLY how it was removed. There balanced from the factory.

Edit: I see you had it rebalanced; I have no idea I hope someone can chime in for you.

[econti]

Could a bad CV cause this? There's no clicking or anything, only the vibration.
No grease has leaked from them that I know of.
Just spitballing as I'm fresh out of ideas right now

[Wanganstyle]

Wheel bearings?

[econti]

Wheel bearings?

No movement and they don't heat up at all.


I have been informed that the splines between the two halves of the driveshaft are not symmetrical.
When I removed the shaft, I did so in two halves. And there are no factory markings.
SO, I'm hoping that it's flipped incorrectly, and is a minute amount out of perfect phase, and that's the issue.
Will confirm tomorrow.

[Wanganstyle]

No movement and they don't heat up at all.


I have been informed that the splines between the two halves of the driveshaft are not symmetrical.
When I removed the shaft, I did so in two halves. And there are no factory markings.
SO, I'm hoping that it's flipped incorrectly, and is a minute amount out of perfect phase, and that's the issue.
Will confirm tomorrow.

Wheel bearings don't need to show play to be doneski.

They also won't heat up.


(I just replaced 4 wheel bearings on my e36m this January to solve a vibration....

there was just a slight vibration that didn't go away with brand new guibo/center bearing/ 0 mile differential (not junkyard)

[econti]

Wheel bearings don't need to show play to be doneski.

They also won't heat up.


(I just replaced 4 wheel bearings on my e36m this January to solve a vibration....

there was just a slight vibration that didn't go away with brand new guibo/center bearing/ 0 mile differential (not junkyard)

What sort of symptoms then? All the other busted wheel bearings on other cars have done the heat/movement/clicking thing, and there's none of that on mine.

[econti]

Ripped the driveshaft out today and had a look. Confirmed with 3 other people that the splines are in fact not symmetrical, and it was very slightly not in phase.
You can't tell if you just look at it. But if I have it as it is, then flip an end 180 degrees, you can absolutely tell the difference.

So, it's back to the shop on Monday for him to balance it. And that should be the fix.

[Wanganstyle]

What sort of symptoms then? All the other busted wheel bearings on other cars have done the heat/movement/clicking thing, and there's none of that on mine.

symptoms:

vibration pulsing at freeway speeds; kinda a howling noise. sometimes would show at slow speeds also.

it drove me insane;

I replaced this January:

Guibo, Center bearing, Driveshaft, rear ball joints, rear trail arm bushings,
front wheel bearings, 0 mile new diff (actually new), rear wheel bearings.

@ rear wheel bearings the howling noise went away.


This was utter hell to do laborwise; even with a lift and air tools - NO FUN

[econti]

So. It seems to be fixed.

Took the d/s to the shop, guy looked at it, he didn't think that being that tiny bit out of phase would be an issue but I paid him money so he balanced it again.
Fitted it tonight, and it all seems to be perfect.

So gents! Take note! Mark your shit when you remove it, as despite what I was told it absolutely does matter that it goes back exactly as it was!