2007 Tahoe Front Diff fluid.

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dpx2

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Have another question for you folks. I've recently, like very recently, decided to start doing my own maintenance on my 2007 Chevy Tahoe.
Today's job was to replace the front differential fluid. The truck has 175k miles on it and I don't think the front diff oil has ever been changed. Yes, my bad, I know since I've owned it 75k of those miles.
The process started 5 days ago, but when I couldn't get the fill plug out, I started the process of soaking it with some penetrating oil for a few days, tried again, soaked it some more, and today I finally was able to break through the corrosion and get it off. I then drained the diff oil. I figured it would be low for a couple reasons. While I don't have any drops of oil on my garage floor, there is some oil splashed on the case and around the general area. In addition to that, the last few weeks I noticed a hum coming from underneath. I assumed it was the front differential.
Well, I got about 34oz out of it, so I was about a quart low. I'm curious about what damage might have occurted from it being this low. The oil that came out was black. The fill plug had, what I would say from watching youtube videos, normal metal flaking, but no metal pieces on it. It wasn't any worse than others I saw on the videos. I had the front end off the ground and rotated the wheels and noticed no rumbling, grinding, or side to side play when I tried to wiggle them.
Curious as to what damage may or may not be present. I haven't been able to drive it yet as my ECM was shipped off for a AFM Disable and I haven't got it back yet. Anything I should be looking for besides listening if the hum/whine goes away? Is 34oz of oil enough to lubricate everything it needed to? TIA
 

Geotrash

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Have another question for you folks. I've recently, like very recently, decided to start doing my own maintenance on my 2007 Chevy Tahoe.
Today's job was to replace the front differential fluid. The truck has 175k miles on it and I don't think the front diff oil has ever been changed. Yes, my bad, I know since I've owned it 75k of those miles.
The process started 5 days ago, but when I couldn't get the fill plug out, I started the process of soaking it with some penetrating oil for a few days, tried again, soaked it some more, and today I finally was able to break through the corrosion and get it off. I then drained the diff oil. I figured it would be low for a couple reasons. While I don't have any drops of oil on my garage floor, there is some oil splashed on the case and around the general area. In addition to that, the last few weeks I noticed a hum coming from underneath. I assumed it was the front differential.
Well, I got about 34oz out of it, so I was about a quart low. I'm curious about what damage might have occurted from it being this low. The oil that came out was black. The fill plug had, what I would say from watching youtube videos, normal metal flaking, but no metal pieces on it. It wasn't any worse than others I saw on the videos. I had the front end off the ground and rotated the wheels and noticed no rumbling, grinding, or side to side play when I tried to wiggle them.
Curious as to what damage may or may not be present. I haven't been able to drive it yet as my ECM was shipped off for a AFM Disable and I haven't got it back yet. Anything I should be looking for besides listening if the hum/whine goes away? Is 34oz of oil enough to lubricate everything it needed to? TIA
Should be fine. I wouldn’t sweat it. The hum can be anything, but you’ll know it when you have a bad bearing in your front diff. It’ll sound more like a low howl.
 

me88

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Unless the vehicle was at a sideways angle I doubt you overfilled it. I filled mine on level ground and I think about 1.5 quarts went in before it flowed out of the fill hole.
 

Doubeleive

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if there was no metal and just fine silt looking stuff on the magnet you are fine, fluid being a little low wouldn't do any damage.
fill it and just check it once in a while. I personally do not like leaks of any kind at all, but if you check the level once a while it won't be a issue.
if you want to find the source of the leak spray it all over with purple power and pressure wash it and wipe it all down then drive it and check it out with a flashlight daily after getting home from the daily routine.
 
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dpx2

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There was no metal on it, just the silt looking stuff on the drain plug you described. Being a little OCD, I pulled about 13oz out of it yesterday, which leaves me about 3oz over, which I can sleep at night with.
Got my ECM back from LT1Swap yesterday and it fired right up. I'll take it for a drive today and see if the hum/whine I had is gone or not. Crossing my fingers. Hoping it was just because of low/old fluid.
I changed the fluid in my garage which isn't level, so no fluid came out the fill plug when removed, even though it was overfilled. I'm going by what I have left in my 2nd bottle to calculate what I put in the diff.
I don't like leaks either, but there is no oil on my garage floor, so after 175k miles, it must be a pretty slow leak. Thanks for the suggestion on determining where the leak is.
 
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Doubeleive

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There was no metal on it, just the silt looking stuff on the drain plug you described. Being a little ****, I pulled about 13oz out of it yesterday, which leaves me about 3oz over, which I can sleep at night with.
Got my ECM back from LT1Swap yesterday and it fired right up. I'll take it for a drive today and see if the hum/whine I had is gone or not. Crossing my fingers. Hoping it was just because of low/old fluid.
I changed the fluid in my garage which isn't level, so no fluid came out the fill plug when removed, even though it was overfilled. I'm going by what I have left in my 2nd bottle to calculate what I put in the diff.
I don't like leaks either, but there is no oil on my garage floor, so after 175k miles, it must be a pretty slow leak. Thanks for the suggestion on determining where the leak is.
the procedure to fill the front diff is to fill it until it starts to come out the fill hole. it's nearly impossible to overfill it unless you used some kind of pump to overfill it and then slapped the filler on cap super fast before the overage spilled out.
or as previously mentioned had the drivers side jacked up only and proceeded to do the same.
 

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