Slip joint orientation

According to the TM, the slip joint is to be installed "forward" when mounting the drive shafts. After a casual search (google also), nothing pops up to explain this, so why is it important?
I assume "forward" means towards the front of the vehicle and may have something to do with exposure of the seal to dirt and debris perhaps?

I think to let water drain out?

Re: RE: Slip joint orientation

sermis said:

I think to let water drain out?

Click to expand...

They are not all tilted down....
From the 2320-260-20 TM page 2-240, the slip yoke is always at the "power input end", so the drive shaft shown in the image from the transfer to the 2nd axle is not installed correctly.

On the 5 ton it allows the shaft to clear the trans at the point where a pto would be installed on the drivers side of the tranny.We had a truck that had it installed with slip joint to the frontand it peeled the heads off of the bolts holding the cover on the tranny. This is for the front drive shaft.