Acceptable front driveshaft play? Front drive diagnosis?

[fredekr]

Hi everyone -- trying to diagnose my 4wd clunking and grinding problems. One thing I noticed is that the front drive shaft has about 1/8 rotation of play before it "catches" -- it's the same whether I have the hubs locked, or the xfer case locked (203), or both. Does that sound acceptable? The only comparison I have is the rear which is very tight.

The u-joints look solid (no play). I took the cover off the front diff (Dana 44) and it looks okay too with little visible slop; the oil was very dirty but I couldn't see any metal in it. The hubs are new Warns (not premium).

I'm suspecting xfer case problems (it already pops out of 4hi+4lo), I suppose a good thing would be to drain the xfer case and check the oil for metal bits. What else should I be looking at?

thanks,
Kevin

 

[K5thatShmobs]

If its when you hit the gas, it could be the CV shaft on the front driveline slightly coming down and grinding against the crossmember. Thats what mine did--You should check it out.

 

[Leadfoot]

Your front splines might be toast (or close to it). It is probably a good idea to pull the front shaft, separate the slip portion and check the splines. If it looks good, reassembly, grease, and re-install. If the splines don't look good....then fix em. /forums/images/graemlins/thumb.gif

 

[bigjbear]

Before you pull the front shaft appart mark it so you can putit bak together the way it came appart.

 

[Ryan2286]

why do you have to mark the shaft to put it together the same way?

 

[Leadfoot]

Basically if everything was self balanced you could assemble a front shaft with CV in any orientation but prefereably in line with the H yoke. On a regular slip shaft or slip yoke non-CV driveshaft you have to have the u-joints in phase to cancel the accleration and deceleration of the joints. The way to do this is to keep the ends of the driveshaft "inline" with each other. It can be put together correctly in only two positions (180* from each other).
In the real world everything is not perfectly balanced, so after a shaft has been balanced in one position, if it is disassembled, it should be reassembled in the same exact orientation. Even though putting it back together 180* off with keep the u-joints "in phase", you will more than likely have balance issues.

I could be wrong (if I am correct me), but this seems to be the consensus all around.