White Diff Fluid

[BobsArmory]

So here I am changing both my diffs on my 2009 Silverado 1500 with the Max Trailer package (22,300 miles). I drop the rear fluid and it comes out black and fill it up with Amsoil Severe Gear. I then change out the front Diff and it comes out white. I ran out of light so I didn't refill untill this afternoon. I got under the truck and wiped my finger along the inside and the residue inside still looked like lithium after sitting overnight.

Now I have to say that I know that water contamination will show milky but this stuff looked just like it had a lithium base to it. Is it possible that GM put in an odd type of diff fluid in the front end or do I have water contamination for sure?

 

[tinmanSC]

Hum... here are the specs for the Silverado. Nothing in here about special lubricant for any of the models.
Front Axle
(1500 Series) -
Four-Wheel Drive
SAE 80W-90 Axle Lubricant
(GM Part No. U.S. 89021671, in Canada 89021672).

Front Axle
(1500, 2500 HD, and 3500 HD Series)
SAE 75W-90 Synthetic
Axle Lubricant
(GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115.

 

[xxch4osxx]

My silverado had regular color fluid in the front diff when I changed it. No idea why yours would be white in color.

 

[CarbonSteel]

Originally Posted By: BobsArmory
Now I have to say that I know that water contamination will show milky but this stuff looked just like it had a lithium base to it. Is it possible that GM put in an odd type of diff fluid in the front end or do I have water contamination for sure?

I have different brand of truck, but I thought the same when I changed mine at 13,300 miles. It was a honey color in the front differential and a gray color in the rear. A UOA confirmed there was zero water in either of them, perhaps you should send yours in for a test? It could simply be a new formulation of the oil.

Here is the link to the post of my front differential including a photo of the oil:

FX4 Front DIfferential UOA

 

[oggb]

I was going to say either water or lots of wear metal. Does it feel gritty?

 

[BobsArmory]

Couldn't really feel any gritty stuff in the oil. There was some metal on the magnetic plug but not an excessive amount.

 

[Jim Allen]

I had white fluid come out of the axle in my F150 as well, with only about 10K miles on it. It was just the color of the oil... or lack thereof. Sometimes they put dye in and sometimes they don't. Like FX4 said, you could have it tested (though now that you dumped it into a pan, it's probably contaminated).

You probably didn't use four-wheel drive much, so the oil in the front diff would be pretty much virgin stuff. The back was oxidized and went dark because it was in use all the time. In all likelihood, it's a "no worries" thing.

 

[Ken2]

Bob

Did you check the level of that differential early in its life, and do you remember what it was? If the level raised and turned white---water. In any case, water is likely the problem. Due to the high proportion of additives in gear oil the water will never settle out. You might need to upgrade the vent on that differential housing, or avoid fording deep rivers.

 

[Mr_Joe]

I went through my 2003 4x4 GMC a while back. I went with amsoil synthetic in both differentials. I think it was spec'ed a little different for each. It's not something I change all that often so I wanted to put upper end fluid in.

 

[gomes512]

Not contamination, probably just an assembly grease.

Has the front diff. been worked on before?

Mine looked like that after a locker install, required greasing before reinstall.

 

[Mike_dup1]

I seen a service bulletin that said if the gear lube appeared white from the front differential is was due to a dye used in the assembly process by the differential manf. and had no bearing on the lube.

 

[Mike_dup1]

Btw

Its perfectly fine to use synthetic 75w-90 in both differentials. Only reason 80w-90 is spec'd for front it that its only in use part time and thus no fuel savings are gained and regular 80W-90 is cheaper to acquire. That's the only reason, cheaper lube.

 

[BobsArmory]

The Diff has never had any work done on it before. I did a couple water crossings while hunting in Wy but I don't think I ever went past the hubs. I think I will take it over to the dealership and see if I have a faulty breather. I think that I will sample it in a couple thousand miles to look for water contamination.