Rear Diff oil w/pics

[maxhunter]

Ok, so I gotta say, THIS FORUM ROCKS!
I read read read....I have heard a couple folks here say that the rear diff oil need to be changed.
Most are reporting nasty smelling and looking oil, metal filings etc.

Well ours is a 2LT auto car. I did an oil change at 500 miles and now we are approaching 1000 so I figure while I am at it I will go ahead and do the rear differential fluid.

So is this what you are all seeing?!~?











Well to say the least I was suprised to see that much metal on the drain plug in just 1000 miles.
I will probably go ahead and change it again in 1000-1500 miles just to see what it looks like then.

[ackeight]

It is supposed to have the metal shavings in the rear diff like that during the break in. If you see that in engine/tranny oil I'd crap myself.

[Russell James]

Yup, that is the muck that comes out. Mine looked the same at about 500 miles. I think the clutches shed a lot of material when breaking in. Ring and pinion probably makes some metallic paste too as it wears in.

[SSLarry]

Yuck!!

That's it, I'm changing mine this weekend (3300 miles)

[Scott@Bjorn3D]

Also the drain plugs are magnetic to collect the shavings.

[GQ4Life]

how much it cost to have dealer change diff fluid? I got like 19K miles on mine.

[naga]

ooooooooooooooo crap i need to change mine asap 13800 miles and haven chaged the diff oil at all!!!!

[naga]

What diff oil did you go with and how quartz did take for the diff??

[SSOOCH]

It's not muck or metal shavings. It's been covered 10,000,000x before! The milky residue will subside after a while.

Now having said that, I changed mine out at 1500 miles.

[naga]

Originally Posted by maxhunter

Ok, so I gotta say, THIS FORUM ROCKS!
I read read read....I have heard a couple folks here say that the rear diff oil need to be changed.
Most are reporting nasty smelling and looking oil, metal filings etc.

Well ours is a 2LT auto car. I did an oil change at 500 miles and now we are approaching 1000 so I figure while I am at it I will go ahead and do the rear differential fluid.

So is this what you are all seeing?!~?











Well to say the least I was suprised to see that much metal on the drain plug in just 1000 miles.
I will probably go ahead and change it again in 1000-1500 miles just to see what it looks like then.

What brand of oil did you use on your diff??

[Toasty]

the milky color is from the marking on the gears durring assembly. the milkyness will disipate.

[maxhunter]

NAGA--I went with Mobil 1 LS 75W90 1 qt brought mine up to the bottom of the fill hole. I am sure there are alot of gear oils that will be fine, but I have read here that the Mobil 1 is what some of the dealerships are putting in them. Good enough for me.

So here are my thoughts. I may be over sensitive to this subject but... in my experience....and I have set-up rear ends by myself, very successfully, and I NEVER used so much marking "paint" that it turned my gear oil that color.
I don't know what the factory is using and I am by no means an expert. It may very well clear up.....but with the drain/fill plugs being magnetic, ferrous metal is coming from somewhere... the gear set.
One reason I went ahead and changed out the fluid IS because of the reports I read about here.
I did not want that stuff running around in my axle housing, our cars having the IRS,
the fluid capacity is less than a live axle. A lot less fluid for the same amount of metal to be floating around in.
I know the plugs are magnetic and applaud GM for using them!. But after you have so much metal building up on it, I am sure that there will be a saturation point. That is to say that sooner or later it can not hold onto any additional metal....So it stands to reason to me, that if there is metal in the fluid that is not being held by the magnet, it is running through the bearings (ouch).
So for me...the $9.00 for a quart of gear oil was a no brainer. I'll change it again in about another 1500 miles just to see what it looks like (cheap insurance).
The old oil felt very slick and it did have a slight "funky" smell, which could be from the marking "paint".
I have just never seen anything like that (oil) come out of a new gear set.
So I say it again....thanks for the info, I am grateful to have that stuff out (metal filings) and fresh oil in. I want this car to last a LONG LONG time.

BTW...our last Camaro, our '99, I picked it up used and dirt cheap because the rear end was shot with barely over 100,000 miles. I had to replace all the bearings and the gearset. I don't think the gear oil had ever been changed!
Hey these are just my thoughts for what its worth.

[Russell James]

maybe they are using metallic marking paste now?

Change it, it's crud. Just normal debris that sheds off every clutch type diff.

Also several bulletins out there to change the gear lube and LSD additive. They know it doesn't last long.

[csjcsj]

So in the rear end there is a plug to take out and it drains out? I know my mustang doesnt have one just one to fill in,