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RexDodge 04-02-2012 12:27 AM

pinion angle question
 
3 Attachment(s)
I know this has been covered but I'll ask. In the photos below you will sort of see the pinion angle I have. I have installed a 2" lowering block and coils from an El Camino that should net me around a 5"+ drop. I flipped the trailing arm brackets to correct the pinion angle and now (without the bed or fuel tank in place) I have a slightly upward angle. I think it will work out but I'd like some experience opinions. I am thinking I'll wait until I get the bed on and a fuel tank (or simulated weight) and recheck the pinion angle. At that point I can either fab up some different brackets or install shims. So waddya all think?

Tom Vogel 04-02-2012 09:44 AM

Re: pinion angle question
 
I would flip the cross member back over and use shims 'if' you need to.

turp mcspray 04-02-2012 10:15 AM

Re: pinion angle question
 
Absolutely have the actual weight on it, when setting up the angle.

shawno72 04-02-2012 10:24 AM

Re: pinion angle question
 
...
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RexDodge 04-02-2012 10:41 AM

Re: pinion angle question
 
Quote:

Originally Posted by turp mcspray (Post 5289579)
Absolutely have the actual weight on it, when setting up the angle.

Awesome avatar picture!

shawno72 04-02-2012 11:26 AM

Re: pinion angle question
 
1 Attachment(s)
Ok I found this on another thread.
Attachment 901631

RexDodge 04-02-2012 11:57 AM

Re: pinion angle question
 
Thanks Shawn. With that and some research it looks like the ubber cool trailing arm bracket flip is not a good thing to do. Should have thought that one out a bit and I would not have wasted my time with it...but things are cleaner down there now. Basically my pinion gear/shaft center line needs to match my transmission center line and let the secondary drive shaft do it's work. Hmmm...

CC69Rat 04-02-2012 12:10 PM

Re: pinion angle question
 
1 Attachment(s)
Yes, it looks like the pinion is up a little higher than it needs to be. I usually try to run about 1deg down at the pinion. You don't want to completely zero it out or it will not have proper lubrication in the Ujoint cups. 1-2deg and you'll be fine.

Weight the rear end with what you'll have at finished ride height. Just eyeballing it I would suggest running 3 or maybe 4deg shims.

RexDodge 04-02-2012 12:24 PM

Re: pinion angle question
 
Quote:

Originally Posted by CC69Rat (Post 5289779)
Yes, it looks like the pinion is up a little higher than it needs to be. I usually try to run about 1deg down at the pinion. You don't want to completely zero it out or it will not have proper lubrication in the Ujoint cups. 1-2deg and you'll be fine.

Weight the rear end with what you'll have at finished ride height. Just eyeballing it I would suggest running 3 or maybe 4deg shims.

Props to you, that's a great help! Thanks...

FLEET72 04-02-2012 12:49 PM

Re: pinion angle question
 
Before you go and swap everything back around, measure the angle at the trans and at the rear.

https://lh3.googleusercontent.com/-K...2520finder.jpg

Measure it at ride height and be sure. If you flip it back your driveline will be working as if it were stock, bottomed out condition 5"+ drop and worse when you put anything in the bed.

RexDodge 04-02-2012 01:02 PM

Re: pinion angle question
 
Quote:

Originally Posted by FLEET72 (Post 5289849)
Before you go and swap everything back around, measure the angle at the trans and at the rear.

https://lh3.googleusercontent.com/-K...2520finder.jpg

Measure it at ride height and be sure. If you flip it back your driveline will be working as if it were stock, bottomed out condition 5"+ drop and worse when you put anything in the bed.

Thanks for the advice. I have some work to do on the bed (it's off now). After I get the fuel tank and bed mounted I'll toss some weight in to simulate the load fuel will be and measure the angles then. If needed I'll build some adjustable brackets and dial in the pinion angle.

CC69Rat 04-02-2012 02:25 PM

Re: pinion angle question
 
1 gallon of gas = 6.15lbs @ 68 degrees.

so, 15 gallon tank = roughly 92lbs. My point is you could simulate the weight. It will be easier to shim the rear with the tank out of the way. Just a thought.


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