rear end differential
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Burning Brakes
Joined: Aug 2005
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From: Lewisvlle NC
rear end differential
Changing gear oil in my '88 w/3:07 gears and 4+3 trans. Have read that in order to drain old fluid that you have to drill and tap housing or pump out old fluid. My housing already has a threaded 15mm bolt located in the bottom of the housing at the back. It is about 1.5 inches long. Looks like a drain plug ,but does not go all the way thru. Does anyone know if I can just drill this out for a drain.
Team Owner
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There is no factory drain hole but the accessory catalogs used to have a drain plug kit. You drill a hole into the bottom of the housing just off to the side of the centerline and install a self-threading drain plug.
The best way is to just use a hand pump to suck out the old fluid and replace it. Drilling a hole in the housing "may" weaken it and if you don't drill in exactly the right spot, you may wind up with the plug hitting the ring gear.
The bolts at the rear of the carrier cover beam are used to hold the carrier to it. These bolts won't go into the carrier and if you do drill thru there, you may drill through to the ouside of the front part of the carrier. Even if you did drill into the inside, there would be a good chance for leakage at the bolt face.
The best way is to just use a hand pump to suck out the old fluid and replace it. Drilling a hole in the housing "may" weaken it and if you don't drill in exactly the right spot, you may wind up with the plug hitting the ring gear.
The bolts at the rear of the carrier cover beam are used to hold the carrier to it. These bolts won't go into the carrier and if you do drill thru there, you may drill through to the ouside of the front part of the carrier. Even if you did drill into the inside, there would be a good chance for leakage at the bolt face.
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Larry
code5coupe
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Burning Brakes
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From: Lewisvlle NC
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From: One day you're a Comet...the next day you're dust... Arkansas
Racer
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From: Canton GA
I have no idea what its for... Mine also had some kind of gunk or sealant on it.
