I've been hearing some axle whine on my rear Dana 35c. I checked the fluid and it looks grey, not a good sign. I had put mobile 80-90w synthetic in there back when I got it in Nov 2008. Since, I've been playing in loads of mudd and water, not rivers, but huge flooding puddles from our rain, maybe 1 1/2 - 2 foot deep, my worrie is I have water in there, that's why it's grey. After reading throught the Chrysler manual and the recent post, I should have been changing the fluid every time I played in mud or water.
I put contact microphones on the axle housing, and I can here a steady scraping sound under the right carrier, not sure if it's normal. I put it on the front axle, Dana 30, and it seems both carriers are even louder than the one rear when while it's in 4 wheel, but I can't hear anything once it's out of 4, which seems right.
So the plan is that I'm going to drain them both and refill it tomorrow with standard gear oil (if I'm going to keep playing in water, I'm not going to waste money on syn). I did also find a small leak from the axle tube weld plug (Probably where water was getting in). Everyone was right about the trackbar destroying my rear axle, just too late for me to stop from damaging it. My father-in-law is going to braze around the plug for me.
I'll post some pictures of him brazing it tomorrow.
Long term, I need to upgrade the axles to something stronger with a rear locker. I'm going to wait from them to get worse before I do anything else for now. I'm going to keep my eye out for a used Ford 8.8 in my area that someones taking off a Jeep or whatever. Then I'll slowly rebuild it, rather than worrying about these. If I see another Dana35c with 4.11's, I'll picked it up just as a backup for now. I saw some last month for $100 on Craigslist.