New Owner with clunking sound in driveline

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

rlg999

New Member
Joined
Dec 23, 2015
Posts
1
Reaction score
0
Location
USA
New Owner with jerking/banging in driveline

Hi, I just purchased a 1997 Expedition XLT with the 4.6 the other day. It runs great, looks pretty good, and I got it for a steal. The only issue I've seen so far is that when driving at 55 or higher in 2wd, there is an occasional jump in the driveline, almost like the driveline is binding up and then letting loose. It's similar to when a bad U-joint jerks when you rapidly switch from reverse to drive. I can't really pinpoint if it's coming from the front or rear, but I'm leaning toward maybe the transfer case. It occurs when under a steady speed, driving straight ahead, not accelerating or decelerating. I don't think it's suspension related, as it does it on perfectly smooth asphalt on the interstate. Just for kicks, I switched it to A4wd mode, and the noise doesn't occur. I drove it over 50 miles today in A4WD mode, and it didn't make the noise once. I switched back to 2WD mode, and within a couple miles I had the binding/jerking reoccur. It will do it randomly, maybe 20-30 seconds, up to a couple minutes apart. Anyone else had a similar issue? I've tried searching for clunking sounds on this forum, but they all seem to be pointing to suspension components banging around or u-joints under acceleration or deceleration. I read somewhere on an F150 forum about taking out the slip yoke and greasing it as it tends to bind up sometimes. Is this an issue on the expeditions also? Is there any harm in running in A4WD mode over 2WD, other than a loss of mpg and extra wear and tear on the components, or does it make much difference? Could the clutch or whatever actuates the 4x4 system be moving and trying to pull in or jump out while I'm in 2WD mode, but when I select A4WD mode, it is being held in place and won't move? On a side note, occasionally the ABS light does come on, but there doesn't seem to be any correlation between the light being on and the clunking/jerking/banging noise. Thanks for any input.
 
Last edited:

docraymund

Full Access Members
Joined
Feb 14, 2011
Posts
1,076
Reaction score
109
Location
philippines
Its transmission related. You probably have worn planetary gearset. The clunking sound could come from a badly worn torque converter. You got it at a low price bec the previous owner knew it had a problem. You cannot drive forever in A4WD bec the transfer case might get damaged.
 
Top