'chatter' up front

[jkilday4]

I've been wheeling my Jeep moderate to heavy about ten times or so in the past 6 months. I've had it not quite a year. When wheeling it, often it's over rocks (some skid plate banging; diffs have a couple of scratches - haven't hit them hard though) and in mud/mudholes. A couple of pix showing this:





After I got back from an outing a couple wkends ago, the next day I noticed a 'chatter' up front, can't tell if it's from the drivetrain or bearings or what. Initially during the few days following, it would only make the sound (at least audible enough to me while I was driving) when I would let off the accelerator at about 30 mph. One time it made fairly good chatter at continuous drive (not deceleration). The noise would go away after only a few minutes of driving. I got under it to look; there were a few leaves & junk at the oil pan / bellhousing junction. This last trip I sat in that mud hole above for quite a while to get a pull out. The chatter disappeared after a few days and I thought it was just some dirt or something working it's way out.

Then yesterday, I backed out & took off out of my drive-way up-hill on my street at full-throttle. Chatter is there and it's while I'm accelerating this time. It's definitely rotational, and again, it went away after only 30 seconds or so.

The auto tranny's fluid is in excellent condition - at least what I can tell from the dipstick.

Any clue? Thanks, John

[D4x4Fish]

Drive shaft u-joints

All that mud. Parts need to be greased.

Check your joints, If you have one bad one on a shaft, change out both.(dont be cheap)

Dont forget to check your front axle shafts

While your under there Grease everything!

[mrblaine]

D

While your under there Grease everything!

By all means and while you're at it, take grease nozzle, affix firmly into one ear and continue pumping until all thoughts of driving through mud are flushed completely out of your head. This may take awhile, but trust me, you'll thank me for it later.

[jkilday4]

very funny mrblaine. I'll keep it 'in mind'.

D4x4Fish: Now I can't grease the u-joints, correct? Are you saying if they're bad, replace them? How do I tell if they are bad, just obvious wear? What do I check on the axle shafts & how do I get to the area(s)? thx

[D4x4Fish]

Block the wheels on the jeep.
put transmission in netural
Climb under the jeep and grab the yoke and drive shaft, try to move the 2 parts. There should be no movement between the 2. repeat for each joint. total of 4 joints for the drive shaft.

To grease things, if you dont have a grease zerk, you can always take apart the joint and grease it manually(this sucks)

Next check the slip joint (1 of each shaft) on the shaft same way. a new shaft has little to no movement. As time goes on this will wear, any major movement is bad.

Checking the u-joint on the axles is a little tough depending on the make. If you can't grab the axle shaft, to check for movement. Engage the the front end. grab the driveshaft and move it back and forth looking for movement between the 2 shafts.

The Problem with Water/mud is that no matter how hard to try you can't keep the water out of the moving parts. The heat that is being generated by movement creates a vacuim when cold water hits the warm parts, allowing the water into the warm parts.

Something else you should look at is your diff's. They have a breather tube from the housin to the frame. If the water line was above the tube you have water in the diff's, transfer case and transmission.

I hope this helps. When I was in High school my Dad called me
"The submarine commander"
I spent more on replacement parts thans mod's, so don't be so hard on mrblaine.

[Davisrats]

Exhaust leak maybe?

[ChrisD]

I found out the hard way in my old car that mudd pits lead to trouble...