1 Piece driveshaft vibrations

I just installed a 1 piece Tom Woods double cardon driveshaft to try and eliminate my driveline vibrations. My truck vibrates worse now than it did with the 2 piece shaft. I've measured the pinion angle and I'm about 3 degrees off. Can just 3 degrees cause that much vibration? I've since then parked to truck (don't want to cause any driveline damage) and ordered a set of 3 degree shims. Has anyone else had this problem. My truck is a 2005 4x4 with 5100's w/ 2.5 springs and 2" aal in the rear.

 

Take the shims off. I am running no shims and no vibrations at all with a 3-4 inch lift in the rear. The shims are probably causing your vibrations.

 

I haven't installed the shims yet.

 

I haven't heard of your issue before, but I don't tune into driveshaft issues much. Is it possible for you to stick a GoPro/camera under there while the vibes are happening? What speeds are you getting the vibes at?

 

knowing only one side of the equation will not help.

Your one piece, is it a double cardian joint at the tcase and a u joint at the pinion or two u joints? Whats the working angle of the joint at the tcase and whats the working angle at the rear?

 

My guess (and only a guess) is that it’s not the driveshaft. How and when are you experiencing the vibes?

 

Its a double cardon joint at the tcase and a single u joint at the pinion. there is a 3 degree difference from the driveshaft slope angle and the pinion angle.

 

Try the shims and go from there.

 

So if its double cardian at the tcase and a u joint at the pinion you will want essentially a 0 deg working angle a the pinion. Factor in some axle wrap and id say shoot for .5* of working angle for the rear pinion u joint (axle pointed just below the plane of the driveshaft)

 

Correct if 3 deg off add the 3 deg shims as double cardan (CV) pinion should be zero angle with the driveshaft per TW.



But for others like me who have U-joints on both ends xfer and pinion angle are parallel.


Article and pics at TW site article on
Driveline Geometry 101:
https://4xshaft.com/blogs/general-tech-info-articles/tail-shaft-conversion-kits

Note: Also make sure if vibs continue that your trans mount is not separated/broken as its 15 years old. Videos on site on this.
If you got a 4" shaft make sure clearance with the old center carrier bearing brackets so no hitting/scraping. I have a 3.5" shaft and clearance of 0.75" on each side.

 

Also look into doing the ECGS needle bearing replacement, I did it on my 1st gen and it completely eliminated my vibrations.

 

Already did the ECGS bearing, made a world of difference.

 

Pretty sure I found the problem
https://www.tacomaworld.com/threads/driveshaft-rearend-out-of-alignment.694031/