finding the source of my noise

99 XJ Auto 94K miles

I have been trying to find the source of a 'whirring' noise in my geartrain for a while now.

The noise is a light whirring noise, audible above 35MPH, somewhere on the drivers side, that I thought was coming from the front-end. The brake calipers/rotors/pad were replaced. Swapped hubs from side-to-side. No change.

Just came back from opening deer weekend up in the mountains and I descoverd that when turning right aroudn corners, I have a louder 'whirring' noise; but only when coasting. If I slightly touch the accelerator, the noise will dissaper instantly. I can reproduce it at will.

Sounds like it might be coming from the rear-end - first long drive with the rear seat folded down.

Still thinking front hubs - but I would believe that the hubs would make noise under load (i.e. cornering load) regardless if coasting or not.

Any ideas or suggestions? I'm going to pull the rear drums off - the only part of the jeep I have not been into yet.

Thanks for any ideas.

Whirring noises usually point to the pinion bearings. Check for any play in the pinion yoke. Up and down as will as in and out.

Lincoln

I should point out that it only makes noise in a right-hand turn, then only when coasting - apply just a bit of throttle and it goes quiet - immediatley. A left-hand turn and its completely silent.

I will check the input pinon yokes on both diff's tomorrow.