pinion angle question

[RexDodge]

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]

I would flip the cross member back over and use shims 'if' you need to.

[turp mcspray]

Absolutely have the actual weight on it, when setting up the angle.

[RexDodge]

Originally Posted by turp mcspray

Absolutely have the actual weight on it, when setting up the angle.

Awesome avatar picture!

[shawno72]

Ok I found this on another thread.

[RexDodge]

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...

[shawno72]

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[CC69Rat]

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]

Originally Posted by CC69Rat

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]

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



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]

Originally Posted by FLEET72

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



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]

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.