Pinion angle and vibration

[G Force]

I am experiencing a vibration on the freeway. Can the wrong pinion angle cause this? Also my cars pinion snubber is very close to the floorboard metal and it is adjusted all the way down. Any thoughts?

[Chryco Psycho]

Definatly .... the pinion angle can cause a Huge vibration , it MUST have 5-7* nose down from the driveshaft, anwhere esle it will vibrate

[Plumcrazy]

Check both u-joint angles.  They need to be roughly equal so they cancel out each others velocity changes

['CUDA360]

The tranny mount being worn out can cause that also

[Ghoste]

So can loose transmission to block bolts.  What type of pinion snubber is it?  The MP one generally hits the floor unless you are running Super Stock springs and the new aftermarket screw in types will give clearance with HD springs but it will still be damn close.

[ChargerBill]

I have also had some old timers tell me that the drive shaft could simply be out of phase with either the pinion yolk or the tranny yolk....meaning, you could try to unbolt, rotate the driveshaft 180 degrees and rebolt back on. Sounds simple and like it wouldn't make any difference at all, but these guys swear it will solve one out of every two vibration problems...given that your angles are already correct of course.

[Ghoste]

I don't know about one out of two but it can very definitely happen.  All it costs is your time.

[RallyeMike]

5-7 degrees is best for drag racing set up, but not for high speed driving. Also, the front and rear angles need to be within 1-1/2 degrees of each other. I fought lots of vibration issues related to driveshaft and even destroyed a tailshaft bushing until I set my front pinion angle at 1/2 degree, and rear at 1 degree. Now its smooth as a babies bottom to 150 and beyond. Shims are available to change your axle angle. The factory also provided two 1/8" shims at the trans mount which may have been placed as washers or in-between the mount as shims when the car left the factory. Almost everyone ends up putting them back in as washers or tossing them, so that may have changed your angles. Cheap but fairly acurate angle finders can be purchased for a few bucks.     

Other stuff already mentioned are good starting points. Bad U-joints can also cause vibration.

The snubber should not be causing a road vibration problem at 1-1/2 inches. It will only be contacting the body pan when launching at that height.

[Just 6T9 CHGR]

I have the same type of "cycling" viibration above 60-62 mph

How do you go about checking these angles?

Can you do it with "backyard tools" or do specialty tools need to be purchased?

[Chryco Psycho]

$#10 angle finder will work fine

[Just 6T9 CHGR]

Will this cheapie one work?

http://cgi.ebay.com/Angle-Finder-Dial-Guage-Level-Tool-NIP-FREE-SHIPPING_W0QQitemZ4412298794QQcategoryZ43589QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[RallyeMike]

Thats the type most folks use. Digital ones are cool, but expensive for how often they will get used. They are accurate to maybe 1/2 degree if you have really good eyes and remeasure a few times.