holy_crap

I hope someone can help. I have a 2010 JKU Sport with stock driveshafts, a TeraFlex 2.5" Coil Lift on top of a TeraFlex Leveling Kit. I also have 1.5" Spidertrax spacers with stock 17" Wheels and Rubicon BFG KM tires. Jeep has 40,000 miles.

My Jeep sat for about a month and a half while I was recovering from surgery, and when I started driving it again I noticed what seemed like tire humming noise coming from the rear. I ignored the sound until I realized that the sound only happened when I was pressing on the accelerator pedal. I begin noticing the sound at about 10 MPH and it gets louder as I accelerate until the surrounding air and road noise drowns it out. If I let go of the accelerator the sound stops and regular tire/road noise remains.

I had gone wheeling through deep water a week before my surgery, so thinking that maybe water had entered my differential I replaced the diff fluid today with Mobil 1 synthetic gear fluid, the old fluid was indeed very watery and silver in color. There was a muddy like substance on the magnetic plug which I assume is quite normal. I also inspected the rear driveshaft and it seems OK. The noise is still there.

At this point I don't know where the noise may be coming from or where to begin looking. Could it be wheel bearings? gears? transfer case? transmission? I really don't know where to go from here. I feel comfortable changing my transfer case fluids, maybe transmission fluid as well, but when it comes to gears or wheel bearings I'm not so comfortable.

Any assistance or suggestions would be very much appreciated.

RDH475

Same noise, approx. same lift height, same mileage. = rear CV joint.

holy_crap

thanks for your input. I wondered that myself, I don't know what to look for on the rear CV joint to see if it is the cause. Also, I have a 4 door and I see yours is a 2 door, I'm thinking due to the longer driveshaft on my 4 dr the angle would not be as big of an issue.

Tonka_yellow

Check diff fluid and tranny fluid and transfercase fluid.. this was mine

2010islander

All that spinning and catching traction destroys your cv joints went through 2pairs in on winter with my f-150 and had the same noise you did. My mechanic told me if i wouldve waited my driveshaft prob would of fallen out

Ryan0260

Is there a vibration when this happens?

holy_crap

Yikes, that's pretty much the color of the liquid that came out of my rear differential. It was much more liquid than that though. I changed the fluid with Mobil 1 Synthetic gear oil.

holy_crap

No vibration at all when I drive, I crawled under the Jeep and tried to turn the driveshaft by hand and it would not budge.

2010islander

If theres a high pich squeaking sound its your cv joint theres no vibes or anything just that distinct EEe--eee sound when accelerating at low speeds

Pluke the 2

this noise?

http://www.youtube.com/watch?v=yvCejNP_dgo&list=UUy7sJ0QBoHFc6VOVMlYMWMg&index=22