Offroad Trailblazers and Envoys

14B SF DIY diff cover drain guide.

G80, GU6, GT4, GT5, WTF? This section is for gearing and driveline stuff.

by Jrgunn5150 » Mon Jul 25, 2016 7:15 pm

I posted this on another site, but it pertains here as well. My diff fill plug on my new 3/4 was filled by a previous owner with JB Weld. He also knocked a hole in the cover to fill it, then JB Welded that shut as well. Good thing he was a heavy equipment mechanic so he knew what he was doing :facepalm:

Anywho, it's fairly simple and straightforward, if any of you feel like you can get a benefit from this.

So I bought a chrome diff cover on Amazon, because it was slightly cheaper than a stock replacement.

I bought some arbitrary oil drain plug on Amazon, and matching nut's at my local home improvement store,


Then I held it up top the axle and eyeballed the placement of the stock fill plug, and punched a corresponding location on my new bling cover. I flipped it over, made sure that my plug wouldn't interfere with the diff gut's, and busted out my step drill.


Not exactly rocket science, I just went up in steps until the bolt went through lol. Then I used a 36 grit disc and blew the chrome off the backside where I was going to weld.


Ran the bolt into the nut, snugly. You can see this particular bolt has a magnet on it, but it won't be submerged, so it doesn't much matter.


Realized it would probably weld better without the coating lol, :poke:


Turned my welder up and burned it the :zombie: in there for all eternity, no tacks here, I just went full potato on it, as I really don't want it dropping into the diff on me lol.


And here is the finished product, my chrome got a little discolored, but whatever, it was super easy to put the gallon of oil in this pig it takes,

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by bartonmd » Tue Jul 26, 2016 10:52 am

Good times!
FWIW, it will be submerged in oil when the vehicle is in motion. Fluid is flung all around the center housing when the R&P are moving.

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