Infamous drive line shudder

[03mboomdicker]

I got a 03 Crew sb 8" lift (springs not blocks) with a 2 piece driveshaft. Got a shudder on acceleration through first gear. Heavier shutter the more i'm in the pedal.

Been doing a lot of research on the topic. Don't really want to drop the money on a 1 piece driveshaft. I do have a 1.25 shim under the factory carrier mount too.

The t-case flange is 5* (*=degrees)
The rear diff flange is 8*
Driveshaft before the carrier is 8*
Driveshaft after the carrier is 12*

My thinking is that I need to shim the rear to make the diff flange 5* and put another shim under the carrier mount to make both shafts 10*.

I'm also going to put in a new carrier bearing.

Looking for some opinions on my situation.

[rufaast]

I only have 6" of lift, springs,
and i had the exact same problem, i had to drop my carrier bearing down.
problem solved.
I know somewhere on this site there is a conversion, for every 1" of lift you move the carrier down a specified amount. Sorry i dont know what it is, seems like it was like 3/8" down for every 1" of lift. Id have to measure mine again, but just looking at it, it looks to be 1.5 to 2.0 drop.

[03mboomdicker]

Yea I remember reading something like that at some point but can't remember where it was. Rufaast are your driveshafts on the same angle?

Anyone know about what the carrier drop is for every inch of lift?

[livnlrn]

I was told it was 1/4'' for every inch of lift. I'm having the same problem. I had the 6.5" lift and it drove perfect. Then I added 1.5" more, and I cant get rid of shudder on take off. I have tried everything, from lowering the carrier to shimmimg the rear end. Good luck on your fix. Let us know if u fix it, & what you did to fix it.

[no-tel-in]

I have about 3.5-4" lift in the rear and it does shudder on take off... Brand new carrier bearing too. Any ideas on how much to shim it?

[livnlrn]

Try an inch and go from there. Every truck is different.

[Soot_Life]

well the acctuall shim # varies with driveshaft length.. meaning it would be a very slight difference on a short bed to a long bed..

the best thing to do is drop your carrier bearing to a poin where the Ujoints are all equally angled or close to it with a 2 piece drive shaft there almost always 4 Ujpints so it gives you alot of room to play with..

last resort would be buying high angle Ujoints wich are not cheap if you dont want them to break..

if you had a day off i would get bolts that are about 1 1/2 longer and a handfull of thick washers and just add 1 on each bolt run down the road and repeat till the issue is no longer aparent.. then i would build a spacer to match hieght.

i wouldent recomend washers as a fix due to the possibility of it wraping up yor driveshaft under a hard heavy load

[Raul@Stealth Automotive]

you guys could also have axle wrap... esp if it does it worse when you are accelerating hard..... only way to fix that is traction bars

[livnlrn]

Mine seems to go away when I'm on the throttle hard.

[03mboomdicker]

I'm gonna fool with it this week see what happens. Is annoying as ****.... I'll let you guys know what happens. Its not axle wrap cuase it happens on the slightest of acceleration, not just when i'm balls deep in the pedal.