Binding & clunking when in 4x4 Auto

[Bmun]

Need advice...
I have 2003 Ford Explorer ELT 4x4 with control trac. I have had the vehicle about 4 years. Several times over the years the front end would pop and bind when making hard right turn in 4x4 auto. I understand this issue and never worried about it since it was explainable. Now something new happened.

When moving straight, or turning in 4x4 Auto, the same clunking and popping occurs. It does this when you give a little gas (still going slow). Every 3 - 5 feet it clunks when moving forward. I jacked up the vehicle and checked the front end, no unusual movements, nothing binding, ball joints are not wore out, wheels and drive shafts rotate freely.

I removed the front drive shaft and can drive the vehicle without any clunking or popping. The unit will transfer in and out of 4x4 without issues.

It seems like the 4x4 system is trying to engage more than required for the 4x4 Auto setting (I think I read 13% - 15% somewhere in this forum) and this is causing the clunking and popping but I am not sure.

2 questions:
1) Can we drive the vehicle without the front drive shaft until we figure out the true problem?
2) Any ideas on how to determine the root issue?

Thanks,

 

[RickM]

Sounds like what happens when I'm in 4x4 full time.

 

[zerodevil]

first of all, i run my explorer with out the front drive shaft durring the summer months, and have with out issues, so your probably safe.

Secondly, i have had little experience with these rigs in regaurds to the drive line. If i HAD to guess, i would place money on either of the diffs(drain em both and see if you have any metal particals or if hte fluid has a "burnt" smell to it. or the transfer case...

 

[Bmun]

Thanks for the feedback.

Actually drove it around several hours last night without driveshaft and no problem. I am going to put the driveshaft back in tonight and unplug the diff. Trying to determine if its electrical or mechanical.

I am looking for electrical schematics for control trac system. I am thinking this might be a speed sensor on one of the rear wheels but need to find prints so I can trace inputs first.

 

[My03Explorer]

I have had this same problem, only when I switch into 4x4 high. Whichever way I attempt to turn I get the pop-ing and chugging. Anything that you find out will be greatly appreciated.