If the trans is X degrees down, the rear axle will be X degrees up.
Get one of those cheap angle finders, Speedway Motors sells them, along with Home Depo and others.
You want the pinion parallel to the crank, with 1 1/2 to 2 degrees offset under normal driving conditions. The u-joints need some angle for them to work properly or they wear to fast due to setting in one spot. Most joints can stand up to 4 or 5 degree of angle, thats why most guys install them around 2 degrees, its right in the middle of its range.
If the truck is really lowered, then the pinion could face down instead of up, as long as the two angles are still the same, this would make the drive shaft level in respect to the two end angles.
Race cars, angle the pinion down a few extra degrees so when it hooks up under a hard load, the pinion is at the right angle, with our low horsepower trucks, that shouldn't be a problem!
Joe
