Pinion angle question

[454Sub]

Ok, I know this has been asked over 16 million times and I am sorry, but Im on my phone in the driveway and want a quick and easy answer.

If memory serves the u-joints (non CV rear) need to be within 2 degrees of each other. Well, now that I have my shackle flip installed and blah blah. The t-case is pointing down around 6ish, and with the shim I had from the block lift turned around, the axle is pointing up around 16 or so. Now, I have no idea how much degree the shim is, its about a 1/4in thick tapering to nothing. Big end towards front of truck to compensate for the flip obviously, but man, this is a massive difference, does anyone even offer shims in the 10+ degree range? Well technically higher since I already have an undetermined shim installed. Or am I missing something obvious here? Btw the t-case has no spacers installed to drop it, and I cant run them because it binds my already trimmed out CV front shaft pretty bad, which also needs rebuilt but thats tomorrows problem.

My numbers may not be exactly spot on, I am out here now trying to get a best of 3 on it to get a close enough to be good guess so I can order the shims I need to keep this thing off Harley mode. It could also be possible I am doing it wrong, but this is how I have always done it and its never failed. Maybe someone could tell me how they do it and I can see if my way is good enough for horseshoes.

Thanks

 

[rampage]

From what you describe it looks like you have about a 3* shim, that's assuming it's 5" long. If you take more accurate measurements and match up the orientation to the pic in the link below you can calculate it. You just need to measure 'side a' and 'side b' and hit calculate to get 'angle A'. And yes, about 2* difference is what you want for a non-CV shaft.
http://www.carbidedepot.com/formulas-trigright.asp

 

[Hogback Fabrication]

What's the driveshaft angle?

 

[4X4HIGH]

With a non-CV shaft the output of the t-case and the pinion centerline need to be exactly the same otherwise you'll have vibrations and eat U-joints left and right. When you run a CV shaft you want the pinion centerline to be pointed 2* down from the driveshaft centerline to account for axle wrap under load. Also you need a minium of .5* U-joint working angle but no more than 3* working angle or you'll also eat U-joints.

 

[454Sub]

I can check the angle of the driveshaft itself tomorrow after work and try to get more exact degrees and angles and triangles and everything else. I had to do damage control with the lady after last nights drinking debacle.