Driveline vibration. Rear axle shim help

So like many others im currently chasing down my driveline vibration issues. Currently it is just the takeoff shudder and very slight low speed vibes im trying to get rid of.

Goes away when in 4HI.

Lifted the truck with 2.5" Bilstein 5100s up front
And General Spring 3+1 HD leafs in the rear, with 5100 shocks

Installed ECGS bushing, which helped significantly. But can still feel the takeoff shudder, and slight low speed vibrations.

Tried carrier bearing drop, at 1/8", 1/4" and 3/8". Nothing. Removed CB drop.

Ok so after a lot of time spent messing with the driveline angles, trying out the Spicer XC carrier bearing, even reinforcing the flimsy crossmember that holds the carrier bearing, i ordered a 1 piece, double cardan driveshaft from Tom Woods. Truck FINALLY drives like new again!

 

how about front differential drop? also what does your front cv's look like angle wise?

 

Im pretty convinced that the shudder is from the rear, essentially because of the carrier bearing. Will consider a diff drop next but will try the shims first. CV angle isnt bad in my opinion. Ill post a pic

 

Found Belltech and SPC performance slotted shims. Although they are not steel, they are 1.5° and 2°. Anybody have experience with either? Thankyou

 

Sub'd.

Your CV angles look pretty tame compared to some rigs I see on here.

 

Yea i think the same thing. They aren't harsh at all in my experience with IFS rigs. Even though my rig doesnt vibrate when i put it in 4HI, ive found that the same issue occurs in a lot of people's Tacomas. Takeoff shudder, low speed vibe, even high speed vibe. Goes away when they put their trucks in 4HI as well. And ive seen a lot of people correct the issue completely from messing with the rear driveline angles, and carrier bearing. Or essentially eliminating the carrier bearing with a 1 piece driveshaft. Which id like to avoid for now.

 

Shimmed the rear axle 2°. Huuuuuge improvement. Although the take off shudder isn't completely gone, it is hardly noticeable now. If i really ease into the take off, it won't even shudder. Any speed from 15-80MPH the truck is CADILLAC smooth!

Tried combining CB drop at 1/8", 1/4", and 3/8". But with no success, in my opinion it was worse with any of the 3.

BUT, still not good enough, take off shudder needs to be eliminated COMPLETELY. Next step: take apart the carrier bearing, pack it with rubber to eliminate all of the play that it has and see if it helps. If that doesn't do it, I will calculate the driveline angles, and determine if the rear axle needs to be shimmed more, or less. Im thinking more. One step at a time though! Stay tuned..

 

Have you seen this post?
I was having issues with take off vibrations and this carrier bearing fixed it for me.

 

THANKYOU!
Wow i was looking for something like this...
Still going to try to pack the CB. If it doesnt work, ordering one of those Carrier bearings ASAP!

 

Glad I could help!!

 

Ok so after a lot of time spent messing with the driveline angles, trying out the Spicer XC carrier bearing, even reinforcing the flimsy crossmember that holds the carrier bearing, i ordered a 1 piece, double cardan driveshaft from Tom Woods. Truck FINALLY drives like new again!

 

Glad you figured that out. I know how frustrating it can be chasing something like that down.

Question, how did you decide on going with the double cardan? The consensus from the website was the double cardan was for higher lifts than what you have. Just curious.

 

Website says for 3 inches and more. I have around 3.5 inch in the rear. Plus, double cardans generally turn smoother, so i went with it