totally out of my league on this one and may not call parts by the right name so forgive me. 2004Fx4 with 140k. Was driving it yesterday and heard what sounded like I was dragging a branch under my truck. Going around 70 and it wasn't grinding or anything, more high pitched. Pulled over, looked it over to nothing obvious and carefully drove home. Seemed to drive and shift fine and noise was gone. woke up this morning to find puddles of front diff fluid on my driveway. Could'nt see too good under there so took it to my mech a few blocks away and he lifted it and it looks like its coming from the driver side shaft right at the point where it enters the diff housing and of course it got flung everywhere. He thinks something happened inside the housing and recommends a rebuilt diff and new seals. Again Im using laymans terms. I hate having to pay someone else for something I may be able to do. My questions are is there anything I can do to confirm this such as try to engage the 4x4 or anything else and what would cause this since it rarely goes in to 4x4. Could I have an IWE problem which preceded this. Again, no grinding noises before or now. Of course its now 20 degrees out in Pa now when a few days ago it was 60. It just seems like such an easier job on a lift versus on your back in the driveway. They quoted me like $250.00-$300.00 labor not including the parts. Totally lost on this one and haven't commited yet being its Friday and everything. Thought?
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Solution was a leaky axle seal, or the seal in the body of the diff. Mechanic did both sides for good measure. $550.00