Should i be concerned?

 

There is some scratches in there, I don't know if I should be worried.

 

Put some arrows or something to bring attention to what you're talking about. Looks fine to me...?

 

I'm on my phone uploading pics will edit from pc later, but if the scratching isn't obvious that's a good sign.

 

OK...so this is a relatively recent purchase (many of you know, who have already answered other questions).

99 ram 2500 V10 4x4 3.55 diff.

I leveled the truck, crawled under and changed the rear diff fluid. I was getting some weird vibrations when doing slow tight turns - which could have been related to last diff change not included LSD friction modifier. However, vibrations or no, I was planning on changing it because you never know how long it's been since it has been done, it can be ignored easily.

This pic circles the scratches...which I suspect is not concerning as you didn't notice them before.

However, little more info...I drained out the old fluid (a little grey, but not exactly black) cleaned up the cover (no real major chunks of anything near the magnet).

put in friction modifier for LSD, and put in almost 7 pints of synthetic gear oil (75W-140).

drove it around the neighborhood for about 1-2 miles at slow speed...then checked the level of the gear oil again...and when I pulled out my pinky, the oil that just went in was white/milky.

What the hell? Synthetic mixing with whatever was in there before? Synthetic mixing with the LSD friction modifier?

Am I about to drain it all again?

 

Those "scratches" are fine. In fact they aren't scratches from anything inside the diff. It's from casting those parts when they were built. See how those scratch lines are horizontal? Impossible to make those in the diff unless all hell broke loose in there. They would be longitudinal scratches if something was hitting that part (because it's rotating) Nothing to worry about.

On the fluid, I think you're fine there too. Just the oil mixing up.

 

I agree with this assessment. If you are really paranoid, you could change the fluid again, but, I don't think it's necessary.

 

Looks like you have a Dana 60/70 rear with a Power-lock limited slip unit in it. It looks pretty good and with very basic maintenance (don't ever let the fluid get low), should last a very long time.

 

Confirming here. Those scratches are normal casting marks. Never seen white or foamy oil. But then I've never checked after putting oil in. Pretty easy to know if its leaking. I do mine every two years regular maintenance.

 

I use to be the rearend guy at a few dealerships that I worked at. I setup gears for a living and I can tell you those marks are not anything to worry about just as everyone else has said.