Well I put the 3* shim in and the vibration is just as terrible as before, no change. I may try to get the tires rebalanced and see if that's the problem. Very frustrating to say the least

 

i had to shim mine like 3 times till i got rid of it, shims at the axle twice (different dregree each time) then the trans

 

What are your working angles after the shim?

 

I haven't been able to check because after the test drive I just put it back in the garage and shut the door. I'll see what the angles ended up being with that shim, but I figured even if it was close, the vibration would be less severe. This is like a massive shake that moves the whole bed side to side....

 

Do you have idea of what they should be based on what you measured previously and the direction you put the 3° shim in?

 

Yeah a few posts up shows the numbers. I put the fat end forward so it raised the pinion up to be close to parallel with the tranny

 

So you went from 4.6° at rear to 7.6°. The ideal working angle is 0.5 to 3°. Check out this spicer manual on drivelines.

Edit- Can you put a spacer under your transmission? That's what I did to mine to get it under 3. Maybe space it to get to match the rear without the shim?

 

i think that might be your problem, i was told the thick side always go's to the rear

your working with a 2 peace drive shaft so im pretty sure you want to raise the carrier bearing as needed (or lower it?) so the trans and carrier need to be angled right then from the carrier to the diff needs to be adjusted as needed

both drive shafts need to be in the same slop and NOT form a V

maybe post up in the gmt800 section and you can get help from other crew cab guys to be sure

 

It's a RCSB, it's a single shaft. If I put the big end at the rear that would nose the pinion down and be much further off from the trans angle, which I've been told need to be equal and opposite.

I watched a spider video and they said that u joints like an operating angle of 5°-8° which is why I raised the pinion up to match the trans angle.

I tried raising the trans but even with jacking it up so high that the mounting bolt was out of the hole didn't get it above 4°

 

Ok let’s look at it this way....

the trans was higher then the diff so the driveshaft had the correct Angle, now you lessened the angle when you installed the flip and now you put the shims thick side forward and made is even less


The idea of the shim is to add angle to the diff to lower the front of it so it like or close to what it was before the flip was installed

I was in your shoes it’s a pita my fix was to shim the diff and trans (raise the trans & angle the diff nose down)