The rubber seal where the output shafts go in are just that - seals. They don't hold the shaft in place. It's the bore of the LSD bearings that hold it in place and that's where movement would be.
Like tires, brakes, shocks, wheel bearings, you replace 1/2 shafts in pairs because they "wear" in pairs. Now you have one new one and one old one that may likely be worn and is likely what is still causing some vibration.

 

Well I honestly didn't notice much of a change from replacing the shaft, I could put the original back in since it seemed fine when I inspected it (I did not dismantle it though).

The car is lowered on tein s-techs (iirc) and is running 18" volk te37's with 255's in the rear. I dont drive it hard but I am unsure about the PO.

It seems like I have no choice but to drop the rear end and have the bearings replaced. Each output shaft bearing is about $86/ea ...unless someone knows where they can be purchased for cheaper.

I just hope there isn't more wrong with it then this.

Thanks for all the help thus far!

 

Another question:

If I am already going to have the rear end off the car to replace the bearings is there anything else I should consider replacing?

 

I don't think it's your diff bearings, although you've not stated exactly how much "wiggle" there really is. Since you are lowered, did you install the output shaft to 1/2 shaft spacers? A few people who have lowered their cars and didn't put in the spacers have since discovered that their CV joints are finding new pressure points and this is contributing to accelerative vibration.

 

Well, I didn't measure it exactly but I would say that if you were looking at one of the bolt holes on the output shaft while moving it you might see 3-4mm or play...easy (we are talking up and down play, not in and out).
Its alot compared to the other side, which barely moves at all.

The car was lowered before I purchased it and it does not have any spacers on the shafts (I'd like to find some in the US though).

I do not notice any 'extra' vibration during acceleration or decelleration, its based off of the speed of the car. up to about 40mph its somewhat noticable and then after 70+ it comes back.

Any idea what else it could be? I have the option of picking up a stock rear end for about $650 from a local shop...
I understand its difficult to diagnose something without actually seeing it in person.

 

I agree, this is not normal. I wonder if that end cap has been damaged and has lifted slightly. No vibration on acceleration would likely (but not completely) rule out CV. I concur that it is likely a bearing. Whether it's the one in the diff (more likely due to the play you see) or the wheel bearing may have to be determined by trial and error.

Oh, there have been reports of similar vibrations being caused by missing or loose propshaft bolts.

 

Blue = Torsen housing.
Red = inner bearing ring.
Orange = roller.
Pink = outer bearing ring.

The way I understand it you have 3-4 mm play between the output shaft and the blue part.
Changing the bearing (red, orange and pink) will not fix that.
(does this make you think about Reservoir Dogs?)
If the play is caused by the bearings and the Torsen is moving that much as well you are lucky IMO that you are still driving with that much play in your bearings and ring & pinion setup.
I would recommend not driving your car anymore.

 

He needs to determine if the end caps have lifted. If they aren't torqued down for whatever reason, the bearing is likely toast and would need to be changed when the end caps are tightened down. Now, what may have caused the end caps to come up is another question. Are the bolts stripped?

 

A note about the shaft seals.

If the bearing is worn enough and the output shaft can move around enough then the rubber seal should be leaking oil.

The seal can seal against a little bit of off axis movement from the shaft but it cant seal against alot of movement or even just a little bit more movement than normal.

 

Great replies gentlemen, this is alot of useful information.

I have yet to check the prop-shaft but will do so soon.

The seals are not leaking any fluid, the casing looks dry and did so when I changed the fluid and replaced the cv axle.

I also dont notice any excessive noise coming from the rear end, I do hear a faint whine every once in a while but it does not sound like a failed/failing bearing.

My second guess was infact some defect/issue with the caps...maybe coming loose. It looks like my best bet would be to purchase the used on from the local shop (when it becomes available), inspect it, install it, and then inspect the old one.