Question about my front driveshaft '97 Mountaineer

[JoeMahma]

First of all let me thank you all for sharing your knowledge. I have been helped soooooo much by browsing this forum. Now my question...I have owned my Mounty for a year now and it has always had a bad clunk (sometimes multiple clunks) whenever I accelerate hard from a standing start. I finally decided to have a look at the drive shafts and u-joints and removed both the front and rear shafts one at a time and road tested. The rear shaft and joints are solid. The front shaft's boot is torn (the cv joint at the transfer case side.) I left the front shaft off and took it for a ride and left really hard from a standstill and I had no clunk whatsoever. I tried this three or four times and all was good...no clunks. Put the shaft back on and I have the clunk again. Can I be pretty safe in assuming that the front drive shaft is the culprit? Could it be the transfer case or front diff.? I'm figuring if it was the Transfer case it would clunk no matter which drive shaft I had left off. Any expertise you could give me would be greatly appreciated.

 

[Dan Whitaker]

It is the CV on the front drive shaft. A re manufactured one will run around $225-250.

Look here in the parts for sale forum or post in the parts needed forum. Someone always has a used one for sale. Usually $100 or les.

Welcome to the Forum.

 

[JoeMahma]

Well, I bought a used drive shaft from CougarX and put it on today and I still have the exact same clunk. I even had the truck in for a trans fluid change on Thurs. (two days ago) and the mechanic called me randomly while he had the truck and asked if I knew about the clunk. I told him I thought it was the drive shaft and he said that was exactly what it is. Now I'm hoping it's not the transfer case. Any ideas anyone?

 

[JoeMahma]

Just went out and removed the rear drive shaft and took for a VERY short drive with just the front shaft on...what a racket. Clunked like crazy with the slightest acceleration. Is there some kind of clutch in the borg warner 4404 transfer case? I'm thinking it has something to do with how the T.C. distributes power to the front and rear drive shafts.

 

[rizzjc]

I would think transfer case. Putting a lot more torque on it without the rear shaft in place, I would guess. I thought it was my front shaft too, but I had already had that replaced, so got under the car and had my wife drive over me (ok, not really, but sorta ), and it was definitely coming from the transfer case. Swapped that out with a used one and no problem since.

 

[fraxinusalba]

Is there a significant difference in tire tread between the front and back or maybe different type or size of tire? My 99 did the same thing after I rotated tires once. Let them go too long and fronts were wore more than rear. After rotating the tires, started getting the clunk on hard acceleration (and only on hard acceleration). Like you, thought it might be something in drive train but never could find anything really wrong. Since it just started after rotating tires, decided to switch them back and clunk disappeared. I now make sure I rotate the tires on a more regular basis.

If there is much of a difference in tread on the tires, put the tires with the most tread on the rear and see if that solves the problem.

 

[JoeMahma]

Is there a significant difference in tire tread between the front and back or maybe different type or size of tire? My 99 did the same thing after I rotated tires once. Let them go too long and fronts were wore more than rear. After rotating the tires, started getting the clunk on hard acceleration (and only on hard acceleration). Like you, thought it might be something in drive train but never could find anything really wrong. Since it just started after rotating tires, decided to switch them back and clunk disappeared. I now make sure I rotate the tires on a more regular basis.

If there is much of a difference in tread on the tires, put the tires with the most tread on the rear and see if that solves the problem.

Nope. Brand new tires on it...well maybe 5000 mi. on em.