Shim size calculation

[MarcS]

I just finished my lift and need to figure out what size shims I need for my pinion angle. Been all over the web and now just confused /forums/images/graemlins/confused.gif Here is a pic of my measurements. Any help appreciated. Thanks.

[image]http://coloradok5.com/photos/showphoto.php/photo/14625[/image]

 

[Scrubby]

I'm trying to figure this out myself. From what I have read, I think you are pretty close because the both angles are the same, but you should shim your pinion down a degree or two to compensate for the pinion lifting on acceleration. Mine is about the same and I am only getting vibes when I am on the pedal at about 35-50 mph, so I am going to shim down 1 degree and see what that does.

Does this sound right to anyone that knows something?

 

[MTBLAZER89]

I would like to know which way to go as well as I get similar vibes at 35-45 MPH pretty bad vibes. If I accelerate quickly through 45 I really don't feel them, just maintaining those speeds /forums/images/graemlins/dunno.gif

 

[85mudblazin]

Before I twisted my yoke on my d-shaft I had the same problems my angles were the same and I still had vibes so I took to to get balanced and it curred it so you might try that, I am going to a cv shaft though since I need a new one anyways and I also plan to lift my blazer more, plus I want a STONGER oone when I put my 14bff in. /forums/images/graemlins/thumb.gif
-Chris

 

[84_Chevy_K10]

At that kind of tube slope I certainly hope you've got some big u joints.

I think I'd be turning the pinion up and either getting a CV shaft or lowering the transfer case.

 

[MarcS]

I did a 4" lift w/EZ rides & 35" tires. The rear pinion is pointing up toward the t-case. I got confused when doing the drawing and pointed it down. Called ORD and Steve said to make sure the springs are in correctly (center pins are offset). Going to give him a call today to redo the numbers with the pinion pointing up. See how much of a difference it makes. Thanks for the input, I'll let you guys know what happens.