Jump to content

Front Differential fluid change

TheGreatOne

By TheGreatOne
in Engines & Drivetrain

Recommended Posts

TheGreatOne Enthusiast

TheGreatOne

Posted
Posted

Just curious as to why the front differential fluid comes out sort of milky...or at least the existenceof some white material....anybody who has changed theirs experience this? 

 

I'm not a mechanic....just a weekend DIYer.....so please don't roast me.  Plug had some normal sludge.

20200623_161941.jpg

Z45 Senior Enthusiast

Z45

Posted
Posted

fyi



Gear Fluid Conditions


 

The color of the fluid can be an indicator of contamination; however, some colors can be easily confused with the normal color of some fluids.





New fluid is usually red or light brown. With time and miles, used fluid often turns black. This is a result of the normal chemical process that occurs as the additive package in the fluid degrades. The black color does not indicate that the fluid’s useful life has been exhausted.



When a fluid is a milky brown color, it may indicate that the fluid is contaminated with significant moisture. The fluid should be changed.  Water contamination of the axle lube also creates significant odor and forms corrosive conditions that will cause internal components of the axle to corrode. Milky-colored fluid combined with rust particles is a sign of moisture contamination either from submersing the axle vent, a pinched or misrouted vent hose, or a failed seal that is allowing moisture to enter the axle.



Under 5000 miles (8,000 km) of operation, hypoid axle lube may appear tinted and have a whitish or yellow appearance from the gear marking compound used in the production of the axle.



From GM tech Line

TheGreatOne Enthusiast

TheGreatOne

Posted
  • Author
Posted

Well I definitely wasn't under 5000 miles but it definitely looked like yellowish greenish tint

 

Something like this

Screenshot_20200623-224936_YouTube.jpg

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • fondupot
      Exhaust heat while towing!

      By fondupot · Posted

      You can install tailpipes that direct the exhaust sideways vs the OEM one that goes straight back. There are several on the market, do you own research. HOWEVER, you need to make sure the Venturi vents are still intact, otherwise it will throw a engine code. There is a sensor somewhere that detects back pressure on the exhaust. And if it doesn't collect the correct metrics, it will throw the truck into limp mode. 
    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      "Teardown" is complete. Head surfaces are clean and ready, new intake is prepped and ready. Coolant drained and water pump is removed, radiator is removed, new hoses and pump are ready.   The replacement intake is also from a '95 (with I think 260k, the odometer said). Noticeably less pitting where it covers the rear coolant passages. I'm not sure if that's a tribute to more frequent use, more frequent coolant changes/upkeep, or if the intake was machined at some point. But it appears I found a good one.   My coolant hoses were original, and the lower hose still retained the factory spring inside. It's not really rusty, but it's got deposits all over it. Unsure if I should re-install it (will thoroughly clean it first). Someone said hose technology has gotten better since 1995 (has it?) and I don't need the spring. I think modern EPDM is what made those hoses last from 1995-2026, so it's a question of how much suction can the water pump really pull, and will it collapse the hose without a spring?   I'm stopped and waiting for parts, however.   When I first brought the truck home, the fan was intermittently hitting the radiator shroud. I could see someone had monkeyed with the shroud (put a bunch of cardboard as a spacer between the upper/lower shroud halves. Someone said the motor mounts have likely failed and the engine has sagged. I wasn't sure I believed that. The engine is really solid in its mounts: To remove the old intake I *just* nearly permanently welded to the heads with freshly cured RTV and gasket snot two weeks ago, I literally had to use the arms on my lift and a chain with a bolt attached to the intake to pull it loose. It almost picked the front of the truck off the ground before ....scuuuuuuuuuuup.... I could actually hear the gaskets tearing and it broke loose and the whole truck settled back down. Motor barely moved.   SO, those parts I'm waiting on... The lower radiator mounts/bushings had completely failed. The radiator needs to be insulated from the rad support, and the bushings help the rad stand at the correct height. The plastic "baffle" was also destroyed at some point. Someone had attached the shroud to it incorrectly, overlapping a joint that should have been underlapped, creating another suspect issue potentially causing things to hit the fan. Broken tabs, side is busted off, and it's perma-formed/bent where it was jimmied incorrectly.   The baffle? Unobtainum. Long since discontinued from GM, of course. Aftermarket/capa/chinese? Also unobtanium. In GM's infinite wisdom, it appears there are at least two different variations whether the Blazer is 2 or 4 door, and I can't yet tell if they shared the same part with the S-pickups. Plan B, if I can't find a viable used one, will be to create a bracket to re-assemble the critical joint I need to seal a gap with the shroud. But that will bug me, it won't be...perfect.   The water pump bolts appear to have been installed with...plumber's putty. I guess, sure, if it works...? I've found a few "backyard fixes" like that. Someone's been here before....   If I can't find someone to jam bamboo under my fingernails to fill my free time this week I think I'll install the driver's power window motor and replace the rear door speaker that's inop. I've got a genuine GM "9.5" ohm working replacement. Why GM used a non-standard resistance....nevermind. Of course they did, you can get more sound from a cheap factory amp that way.   And the saga goes on...
    • glenn27
      Different requirements for oil filters?

      By glenn27 · Posted

      // Thank you, also for your  response. More information is always good. This 2013 GMC is most likely my 'forever truck"-I'm 77 and retired...and truck only has 42K on it-very clean-so I try to keep it that way.  Tks again for your  response- glenn
    • smooth68
      Alternate wiring for Kicker sub with Bose system. (DO THIS)

      By smooth68 · Posted

      I started my install this weekend. Everything was pretty straight forward but I ran into one issue with running power through the firewall. The nipple grommet on my High Country already has a small harness running through it - has anyone else ran into this issue? And on the engine bay side, does the wire basically just penetrate the factory wiring boot? I did this on my '22 Trail Boss and it seems much easier but thats been a few years. My other thought would be possibly drilling a new hole adding a rubber grommet just to the lower left of the factory hole. Thoughts?   Has anyone used a T-harness off the Bose amp and obtained power from there? It seems a little odd that such a small amp needs 3 power leads
    • glenn27
      Different requirements for oil filters?

      By glenn27 · Posted

      ///// Ok--Thanks for that info--I could not find yesterday when I looked for the specs on that NAPA filter what I wanted. Their website is not very user friendly. I buy all teh filters for  our three vehicles once or twice a year. Have always run NAPA Gold on everything I own....I buy it thru my Son's account for his business-which he has a Heavy Equipment repair shop-one reason he uses NAPA so much-they have such a full line of coverage for just about anything/anywhere- He gets s  good discount because of volume bought. Anyway-Thank you -Sir for your response.   glenn

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...