97 Mountaineer v8 AWD clunking under acceleration

[Jim Hazlett]

I have a 97 mountaineer that has been making a clunking /slipping noise when under acceleration. Seems to be ok when up to speed. Don't know where to start.

 

[imp]

I have a 97 mountaineer that has been making a clunking /slipping noise when under acceleration. Seems to be ok when up to speed. Don't know where to start.

@Jim Hazlett
Guesswork without more definite information. Check for codes first. If none, determine of noise is occurring in the Transfer Case. Does the noise change materially if driving in a curved path? Feel anything in the steering wheel? Check Driveshafts for U-joint wear. If U-joints are good, try driving a bit with the Front Driveshaft removed. Noise gone then? Implicate Transfer Case or possible front differential. imp

 

[toypaseo]

If the clunking happens when you accelerate from a dead stop, you might need to grease your slip joint...

 

[Rhett]

^^ agree with toypaseo, it could be a dry slip yoke / slip joint. It can also clunk when coming to a stop

It's worth greasing anyway, as that is a lot simpler/easier to fix than digging into the suspension/trans.

 

[Jim Hazlett]

If the clunking happens when you accelerate from a dead stop, you might need to grease your slip joint...

When i accelerate it continues to clunk/bang until i get up to speed and let off the accelrator, could that still be the slip joint. Don't do it comming to a stop.

 

[Jim Hazlett]

When i accelerate it continues to clunk/bang until i get up to speed and let off the accelrator, could that still be the slip joint. Don't do it comming to a stop.

It also seems if your in a turn it wont do it as bad.

 

[imp]

@Jim Hazlett
The slip joint possibility is a good suggestion. I've seen very few failed, especially on 3rd. Gens., which have no up/down movement of the driveshaft, but your 2nd. Gen. does. A slip joint worn enough to make loud noise should be readily detectable by grasping the driveshaft adjacent to the joint and applying force up and down. If worn, movement (and maybe even clunk) will be felt. imp

 

[Rhett]

When i accelerate it continues to clunk/bang until i get up to speed and let off the accelrator, could that still be the slip joint. Don't do it comming to a stop.

It could still be. Since you're AWD a lot of things are moving all the time -- so I lean more toward a u-joint / bearing / slip yoke issue, pretty much in that order. That is where i would start -- u-joints and bearings. All of the dry slip yokes I've ever seen clunked on stops as well as starts, so I lean away from that.