Transfer Case - 1999 Mountaineer 5.0L

[RickMar]

Hello,
Thank you for taking the tine to read this message.
I have a 1999 Mercury Mountaineer 5.0L AWD.
I have been having a problem trying to figure out some chattering vibration I experience when my wheels are turned and I back up or pull forward.
I had a post out hear on April 11,2009 and got some good advice.
Friday I took the Mountaineer to a very reputable mechanic to get his opinion of where the problem lies. I was told it could possibly be the transfer case.
If I drop the front drive shaft (and the chattering/vibration goes away) …the viscous coupling inside the t-case is likely going bad.
In that case I know without a doubt the transfer case is bad and I continue to drive the vehicle with the front drive shaft disconnected and then only have rear wheel drive… would I be driving a time bomb ?
I have seen the “Sticky” about it drifting in park. To prevent this I will always use my emergency brake to keep it stable.
Any information will be very much appreciated.
Thank you,
Rick

 

[KPT]

I was told it could possibly be the transfer case.
If I drop the front drive shaft (and the chattering/vibration goes away) …the viscous coupling inside the t-case is likely going bad.

Are you sure its not the CV in the front drive shaft? It is a common problem...

 

[RickMar]

Hi KTP,
Thank you for your reply, I appreciate it.
I am not 100% sure it is the transfer case. The mechanic that leaned toward a possible transfer case problem is excellent.
It is a horror show trying to track this down.
It is like a rubbing/chattering vibration ....backing up or pulling forward with my wheels turned.
I looked at the CV's and they appeared to be O.K. - but then again, it could be the cause.
Thank you KTP,
Rick

 

[gijoecam]

I would suggest two things: First, you have a fairly knowledgable mechanic leading you down the right path to diagnosing this problem.

Second, you need to do as he says. Drop the front shaft and see if the problem persists. If not, then we can be reasonably confident it's the VC. If it persists without the front shaft in place, then I would suspect a chattering rear limited-slip differential (if so-equipped.... hint: Check the door sticker for the axle code).

Good luck!

 

[RickMar]

Hi Joe,
Thank you for your advice, I appreciate it.
I quess it's time to break out the jack's and tools to disconnect the front driveshaft.

I would do the needed repair myself but I am getting too old now for this heavy B.S.

Thanks again Joe,
Rick