Vibration and fluctuating Speedo

[Panzer4]

Hi guys,

I went for a long drive with a couple of friends the other day, when I started getting some really bad vibration. It felt like the car was trying to shake itself apart. At the same time, my speedo (analog and on the HUD) started fluctuating, which also wouldn't allow me to engage cruise control.

This happened on acceleration and while trying to maintain a constant speed (bit tricky without the speedo). When I let off the accelerator, the car and ride was smooth as silk.

After doing a little research, I'm guessing maybe dirty/worn CV joints, since I haven't checked them in about 2 years (yes, stupid). Also, my guess is the fluctuating speedo and lack of cruise control is caused by the VSS, though I'm not sure if that's affected at all by CV joints.

What do you guys think? Is there anything else I'm missing?

Thanks for your help.

[Panzer4]

UPDATE: Had my car up on a lift today, and turns out both my tie rod bushings are screwed, so I'll change that first and proceed from there. Don't know if that would affect my VSS or something to cause fluctuating speedo readings though.

[brand121]

I had the same problem minus the speedo fluctuation, if you still have the vibration after replacing the tie rod ends, try replacing the cv axles.

[Panzer4]

I had the same problem minus the speedo fluctuation, if you still have the vibration after replacing the tie rod ends, try replacing the cv axles.

Yep that sounds like a good idea and the next logical step. Thanks!

[Panzer4]

UPDATE: Well, got my Tie Rod ends changed and the vibration is pretty much gone.

However, my speedometer is still fluctuating both on the analog gauge and on the HUD as well as my OBD-II L67 Scanmaster. While this happens, my car shifts gear as the speed fluctuates, so I'm still not sure if its a bad speed sensor or a PCM issue.

Any ideas?
EDIT: My odometer works fine despite the fluctuating speedo.