Can I run the car up to speed with the drive shaft off?

Hey all. I am trying to find a driveline vibration and I just replaced my U-joints and found the front one to be going bad, but that didn't solve my problem (vibration actually got worse). It is a lot of work/expensive (7 hour drive 1 way) to get my drive shaft balanced if I need it done. For this reason I was wondering if I can run the car with it off to make sure the vibration isn't in the clutch assembly?

 

Yeah you're right (I have been having a bit of a rough day haha). I also wasn't sure if there would be any difference if something was messed up with the output portion of the trans maybe.

 

I just threw it back in and this time I rotated it 180 just to see if it made a difference. While not moving revving with the clutch pedal in or in neutral feels exactly the same and there is no vibration. The vibration is there while moving under load or just coasting.

I am really confused why the vibration got worse when I installed new U-joints. They were moving freely with no binding or rough spots. I also made sure everything went back in the same direction as when I took it apart.

 

Before I changed the U-joints, the vibration was at certain speed intervals and it didn't seem to make any noticeable difference if it was under load or not. The vibration would get really bad at above normal highway speed and just keep getting worse (I don't normally drive fast, but the couple times I did, I noticed it and it's violent) I am talking 90-100 mph. If it was up to that speed and I let off the throttle then the vibration becomes very violent.

Since I have changed the U-joints, it vibrates more than it did previously and at lower speeds and more violent and the load does not seem to make a difference. I don't even want to drive it on the highway now because it feels like I am going to do some damage since it is vibrating so much. I know it has to be something with the drive shaft since it is the only thing I touched.

 

Yeah they're good. There was no noise or play when I checked.

 

I am not comfortable running it up to highway speed on stands. I did do it running in first gear to check for bent axles and everything looks fine.

 

I just pulled the DS back out again to double check the u-joint installation and everything seems fine. The slip yoke does have a small gouge in it big enough to catch my fingernail. Checked it with a straight edge and calipers and it doesn't appear bent or excessively worn. The car only has 40k miles on it, would you think it is too soon to suspect the tailshaft bushing? I don't see any play in the tailshaft at all.

Since there is nowhere to get my DS balanced locally because I live in the sticks, I think I am going to pick up an aluminum DS from FRPP.

 

That's always in the back of my mind, but I replaced it last year and I don't have the vibration unless I am moving.

 

Got it ordered! Anyone have any clearance issues with the alum DS? I have heard some people saying it hits the ebrake bracket or something.