Ok, there is a little back story here, so bear with me a sec. I do have a couple of questions regarding my diff at the end. Thanks.

Ok, today I changed the gear oil in my Dana 30. Now I am not a great mechanic by any means but this is something I can do. I did the rear 2 weeks ago(Dana 35) and it looked phenomenal inside, clean and done in an hour. The front not so much. 1st off I can tell it's been done before due to the massive amount of RTV that is sticking out from all sides. So much that I had a hell of a time loosening the bolts. I get the bolts off and it takes another 20 minutes to get the cover off, being careful so I don't mar the surfaces. I open it and this is what I see:





Looks to me like whoever did this before went hog wild with the RTV. First off, the dark line on the inside of the cover, is it normal? Is this burnt oil? What's the deal?

So I clean it to the best of my abilities(this is my DD so a job doing is a job worth doing well, right?) and this is what I get:





so there is obviously some surface rust that I can't get rid of. Is this a problem? Is it something I may have to worry about in the future? As you see I did manage to get the RTV off pretty well, so I am ready for my RTV:



Is this good? Too much? Too little due to the rust? The 35 was easy as there was more room around the bolt holes, whereas the 30 holes are closer to the edge?

So I let the gasket set 10 minutes and bolt it back on:



I let it sit another 45 then add the gear oil(PX3 75W90 synthetic) and drive home(using mom's house as she has a garage). Immediately notice the front end is quieter(good right?). So did I do everything right? Is there anything I should be worried about considering the condition of the previous job?

Sorry for the lengthy post, but I figured, get all the details in and as I said I am no mechanic by any means, and who better to ask than some of the XJ aficionados that populate this board. Thanks for looking and any answers(read; validation that I did ok, )

 

Looks like you did a great job to me.

 

Looks great,

But Quieter? What noise was it making before you changed it?

 

x2, I'm curious too...

 

The only way to describe it is as a loud whirring sound. Not a full blown howl like I had in the rear before I changed that, but a steady whir.

Edit: the oil was also brown(not dark, but not light either...) when I took it out, whereas the rear gear oil was a deep blue...

 

Well, if the gear oil was breaking down, I could understand hearing a noise like that...It looks like you did a good job.

 

Thanks guys, I appreciate the votes of confidence! I needed that. Any concern about the surface rust on the cover though?

I was surprised at how "dirty" the front was(the rust, film on the interior of the case, etc.), as my rear diff, was immaculate in comparison, no rust, just really dark oil.

I assumed that since there is less stress on the front since it's not used as much that it would be at least as clean, although I have no idea how often or when the previous owners changed either of them.

 

As long as the differential isn't leaking, I wouldn't worry about the rust.

 

i wouldnt worry about anything if it drives fine now.

it looks better than mine, mine had about 60% water in it and was snot green

 

looks like you did a good job to me.

 

Dang you cleaned that thing extremely well.

 

What did you use to clean the ring & pinion?

 

X2. Doing mine this month. Nice little write up too

 

x2!!! couldnt ask for a cleaner diff! excellant job my son!

 

I just got a can of O'Reilly's brake cleaner, and went to town. I assume that was ok to use. Both my friend who is the mechanic for our equipment(fuel trucks, escort vehicles, etc., he's also been lifting and modding trucks since his teens) at the airport I work at and the guys at O'Reilly's said it would be ok to use. I just let it sit for a while after it was done, so it was all evaporated.