2x4 mode, is the front drive shaft engaged?

[justin_b31]

So to clarify the title:

In replacing the radius arm bushing on my 93 ex I disconnected front drive shaft at the u-joint leading to the differential (near the RA bushing) but during reinstall my torx bit broke so I didn't get the bolts fully seated/torqued.

The question is, is the front drive shaft engaged and turning while driving normally? Or can i drive safely around as long as I don't engage 4x4 high/low?

 

[ahodges]

The front drive shaft is always turning. It's just not engaged to the transmission internally of the transfercase.. If the bolts aren't tight, don't drive it.

 

[Maniak]

Take the front drive shaft off if you can't get it on right.

Its not not getting power from the xfer case when your in 4x2 mode but there is enough internal friction in the xfer case to make the drive shaft spin. Also, if one of your hubs locks it will turn the drive.

~Mark

 

[justin_b31]

thanks for the replies!

 

[rodb]

Does that mean there is a small amount of drag involved and would one get better fuel mileage with it removed ?

 

[Maniak]

In theory, I guess there is a little drag inside the xfer case. That drag is then transferred to the front drive shaft which in turn makes the ring rear turn and even possibly the drive shafts. However, I don't think it is very much drag and if there is enough drag from the front axles and ring gear the front shaft won't turn since it won't have enough torque.

From what I've seen, once things warm up the front drive shafts stops turning. We were watching for this specifically when I was chasing a funky vibration and we noticed after 5 miles or so the front shaft stopped turning.

~Mark