Drivetrain measurements not adding up

[Ted_Z]

So last night I set about measuring my drivetrain angles and lengths. For reference I have a HP-D30, D44A and 3.5" of lift. The point of measuring everything was so I can figure my new driveline angles for
a 8.8, hp44 and 5.5" lift. I need to know the angles in advance so I can get the brackets welded on right.

Anyway, I used a digital level/angle finder and a tape measure and came up with the following dimensions:

Rear axle 8.3 deg.
Rear driveshaft 11.9 deg.
Transfercase output 5.7 deg.
Front axle 4.9 deg.
Front driveshaft 4 deg.

Wheel base 105.5 in.
Front driveshaft 30.5 in.
Rear driveshaft 34.25 in.
T-case ujoint to ujoint 19.5 in.

The floor and rock-rails both measured within a 1/4 degree of level.

HP30:
pinion 1.125" above housing centerline
Ujoint 10.25" out from housing centerline
D44A:
pinion 2.0" below housing centerline
Ujoint 12.0" out from housing centerline

Here is the problem, when I draft the above dimensions in CAD, the front and rear drive lines dont line up. See attached pic.

[chadjans]

What is the degree of your front tcase output?

[Ted_Z]

Same as the rear, 5.7.

I think I found the issue in my measurements. I didn't include the fact that transfercase front output is lower than the rear output.

For a stock configuration (not clocked) how much does the front output hang down relative to the transmission/rear output centerline?

[AgitatedPancake]

D44A:
pinion 2.0" above housing centerline


Your drawing has the rear pinion below the axle centerline, not sure which way you meant to go.

*edit* it looks like you meant to type below in the specs, but you did the drawing correctly?

Also, You ahve the pinion height compared to the axle centerline, and pinion distance from axle centerline, but it doesn't look like you put the two numbers together for the drawing. On the rear axle, the pinion actually ended up on the axle centerline pretty much exactly, because you took the 2" out of the height, then threw in the pinion angle and distance from centerline. Its hard to interpret without knowing how you measured, but shouldn't the pinion be 2" below axle centerline at the u-joint? (same for front?)

[Ted_Z]

Yep, that was a typo, fixed.

My measurements for the pinion location would be parallel to the pinion centerline.

[AgitatedPancake]

Oh I understand now, the plane of the pinion angle crosses the housing centerline 2" below. Gotcha. I was thinking it was supposed to be 2" below housing centerline from u-joint, bad interpretation =P

I can't find anything else wrong, it seems you nailed it with the front output height difference.